JP2007025120A - Radio terminal device, character data display method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a terminal device capable of displaying an arbitrary character in a predetermined character code, while suppressing battery consumption in a sensor node. <P>SOLUTION: The character data display method is applied to a radio terminal device which is provided with a control device for controlling a radio communication circuit and a display device and displays a character message received from a base station on the display device, based on a preset character code, and the radio terminal device acquires the character code from the received message (P811), retrieving only character font data of preset frequent utilization kinds of characters from a pre-stored character font storage part (P813), to search for a character font data corresponding to the acquired character code; and when the corresponding character font data are not included in the character font data storage part, as a result of this retrieval, the radio terminal device demands the character font data with respect to the base station (P821), downloading the character font data from the base station (P823), converting the character font data acquired from the retrieval or downloading into a drawing data and outputing the data to the display device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control method and a character font data storage method for displaying an arbitrary character or the like by a command via wireless in a small sensor network terminal with a display function. The present invention also relates to a method for realizing such a wireless sensor network terminal with a small size, light weight, low cost, and low power consumption.

  In recent years, a network system (hereinafter referred to as a sensor network) in which a small electronic circuit having a wireless communication function is added to a sensor and various information in the real world is taken into an information processing device in real time has been studied. A wide range of applications are considered for sensor networks. For example, a small wireless sensor network terminal is configured by a small electronic circuit in which display devices such as a wireless circuit, a processor, a sensor, a battery, and a liquid crystal are integrated. A medical application is also conceived in which the monitor is constantly monitored, the monitor result is transmitted to a diagnostic device or the like by wireless communication, and the health condition is determined based on the monitor result (for example, Patent Document 1).

  Also, in order to put the sensor network into practical use, an electronic circuit (hereinafter referred to as a sensor node) on which a wireless communication function, a sensor, and a power source such as a battery are mounted is maintenance-free for a long time and sensor data. It is important to continue to transmit and to reduce the outer shape. For this reason, development of a sensor node that can be installed anywhere is very small.

In addition, in mobile terminals such as mobile phones and PDAs, all character font data is stored in the ROM, and external characters such as model-dependent characters are necessary to reduce the ROM capacity while displaying arbitrary characters. There is a known download from a server in response to the above (for example, Patent Document 2).
JP 2000-04-1952 JP 2005-157891 A

  By the way, the wireless sensor network terminal mounted on the human body or the like does not need to display a large number of characters at all times, unlike the mobile phone or PDA. However, when a health condition based on the biological information measured as described above or an answer based on a response request from the wearer is transmitted to the wireless sensor network terminal and displayed on the display device, a normal character font is required.

  Here, in the wireless sensor network terminal, it is necessary to realize extremely long-term operation by replacing the battery or charging cycle as much as possible while reducing the size and weight. ROM and RAM mounted on a one-chip microcomputer There is a problem that an area for storing character font data cannot be secured.

  For example, in a wireless sensor network terminal, in addition to a one-chip microcomputer, when a ROM that stores all kanji characters that are normally used (for example, JIS level 1 and level 2) is added, the mounting area increases and the device In addition to difficulty in reducing the size and weight, the power for accessing the external ROM increases during display, which significantly impairs the battery life.

  Therefore, the present invention has been made in view of the above problems, and a terminal device capable of displaying any character in a predetermined character code while suppressing battery consumption and reducing the size and weight of the device. The purpose is to provide.

  The present invention provides a character data display method in a wireless terminal device that includes a control device for controlling a wireless communication circuit and a display device, and displays characters on the display device based on a character code set in advance for a message received from a base station. The character code is acquired from the received message, and the character font data corresponding to the acquired character code is preliminarily stored only in the character font data of the frequently used character type provided in the controller. If the character font data is not found in the character font data storage unit as a result of the search from the stored character font data storage unit, the character font data is requested to the base station, and the base station Character font obtained by downloading the character font data and searching or downloading Converts over data to the drawing data output to the display device.

  Further, when the control device is initialized, a hash table for dividing the character font data storage unit into a plurality of sections based on a preset number of elements is set, and when searching from the character font data storage unit, A hash value is obtained based on the character code acquired from the message and the number of elements, the partition corresponding to the hash value is acquired from the hash table, and character font data corresponding to the character code is searched in the partition. .

  The character font data storage unit includes a ROM area that holds only the character font data of the preset frequently used character type, and a rewritable RAM area that stores the downloaded character font data, A hash table is set when the control device is initialized, and a plurality of sections corresponding to the number of elements of the preset hash table are set in the ROM area and the RAM area, and searched from the written font data storage unit. The step searches the RAM area if there is no corresponding character font data after searching the ROM area.

  Therefore, according to the present invention, when a message is transmitted using a preset character code, only the character font data of a preset frequently used character type is stored in advance on the wireless terminal device side and included in the message. Since only character codes that do not have character font data are downloaded from the base station and displayed on the display device, the communication time with the base station is greatly increased compared to downloading character font data every time. The necessary characters can always be displayed while shortening the display processing speed of the wireless terminal device and reducing the power consumption. In addition, the memory capacity required for the wireless terminal device can be reduced, and the reduction in size and weight and the reduction in manufacturing cost can be promoted.

  By dividing the character font data storage section into sections corresponding to hash values, the processing time required for character code search can be greatly reduced, and the processing time of the control device can be reduced to reduce power consumption and processing. Can be speeded up.

  Further, by storing the character font data downloaded from the base station in the RAM area so that it can be reused, it is possible to reduce download opportunities and reduce the power consumption of the wireless terminal device by shortening the communication time.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing an outline of a sensor network (hereinafter referred to as a sensor network) to which the present invention is applied. The sensor network is a bracelet type (or wristwatch type) sensor node (terminal device) SN1 as a wireless sensor network terminal, and mainly measures the pulse and temperature of the user (wearer) to perform user health management and message transmission.

<Outline of sensor network>
In FIG. 1, SN1 to SN3 are bracelet type sensor nodes attached to a plurality of users. These bracelet type sensor nodes SN1 to SN3 perform wireless communication with the base station system BS10 by the wireless WL1 to WL3. Each sensor node SN1 to SN3 transmits data such as temperature and pulse sensed at a predetermined time interval to the base station system BS10. When the base station system BS10 communicates with each of the sensor nodes SN1 to SN3, if there is a message addressed to each of the sensor nodes SN1 to SN3, the base station system BS10 transmits the message using a predetermined character code (for example, shift JIS). As will be described later, the base station system BS10 transmits necessary character fonts in response to requests from the sensor nodes SN1 to SN3.

  The base station system BS10 is connected to a server system SV200 and a user display system UC300 at remote locations via the wide area network WAN10. The base station system BS10 transfers the sensing data detected by the sensor nodes SN1 to SN3 to the server system SV200 and the user display system UC300, and sends a message from the server system SV200 and the user display system UC300 to the sensor nodes SN1 to SN3. Forward to. The wide area network WAN10 may be configured by the Internet or the like, or may be a combination of LAN and WAN.

  In addition, other base station systems BS20 and 30 are also connected to the wide area network WAN10, and transmission and reception of sensing data and transmission and reception of messages between the sensor nodes under the base station systems BS20 and 30 and the server system SV200. Is done.

  In addition, the sensor nodes SN1 to SN3 are provided with a switch SW1 that requests a response in an emergency or the like. When the user operates the switch SW1, a response is made to the user display system UC300 via the base station system BS10 and the wide area network WAN10. Notify that there was a request. The user display system UC300 is operated by a sensor network administrator or the like, creates a message for a response request from the sensor nodes SN1 to SN3, and transmits the message to the sensor nodes SN1 to SN3 that requested the response.

  The server system SV200 mainly collects and stores data sensed by the sensor nodes SN1 to SN3, and the server system SV200. These data can be analyzed as necessary to determine the user's health status.

  Next, configurations of the sensor node SN1, the base station system BS10, the server system SV200, and the user display system UC300 that constitute the sensor network will be described below.

<Configuration of sensor node>
First, the outline of the configuration of the bracelet type sensor node SN1 will be described with reference to FIG. The bracelet type sensor node SN1 includes a one-chip type microcomputer semiconductor integrated circuit chip (CPU1, hereinafter abbreviated as a microcomputer chip), a crystal resonator (X1, X2) that generates a predetermined clock signal, and a base station system. A wireless communication interface (RF1) that communicates with the BS 10, a display device (LMon1) that includes a display unit such as a liquid crystal and displays information such as characters, and a user who requests a response from the user display system UC300 and the like An interface switch (SW1), a real-time clock circuit (RTC1) for communicating with the base station system BS10 at predetermined intervals (for example, 5 minutes), and sensors (Sen1, Sen2, Sen3), LED display (LSC) to call attention by light emission, sound Buzzer (Buz1) for attention Ri, battery supplies power (BAT1), expansion connector provided with various signal lines and (CN1), an antenna (ANT1) for performing wireless communication.

  In addition to rewritable random access memory (RAM) and non-volatile memory (ROM) equipped with a control program for the bracelet sensor node SN1, the microcomputer chip CPU1 can exchange data with the outside via serial communication. Serial interface circuit (SIO), external interrupt circuit (IRQ) that implements program interrupts by external signals, programmable input / output circuit (PIO) that can be controlled by the installed program, and analog signal processing inside the microcomputer chip An analog-to-digital conversion circuit (ADC) that can convert to a possible digital signal, a clock generation circuit (OSC) that generates a clock signal necessary for the operation of the microcomputer chip CPU1, and the like are integrated on one chip. Although not shown, the microcomputer chip CPU1 includes an arithmetic processing unit, and the arithmetic processing unit includes various registers and flags.

  These circuit blocks are coupled to each other by an internal bus so that data can be exchanged and controlled. This microcomputer chip is operated by a clock signal generated by the crystal resonator X2 (a ceramic resonator can also be used). A type in which the wireless communication interface RF1 is integrated on the microcomputer chip CPU1 on a single chip can also be used.

  In the random access memory RAM built in the microcomputer chip CPU1, as will be described later, a built-in character font hash table, which is a data file unique to the present invention, is used to implement a character display method and a character font storage method unique to the present invention. (FHASH1, hereinafter abbreviated as hash table), download character font data file (FNTDL1, hereinafter abbreviated as download character font) for storing character fonts received from the base station system BS10, and characters requested to the base station system BS10 An area such as a download request character font data file (FLIST1, hereinafter abbreviated as request file) for storing fonts is set.

  Further, the nonvolatile memory ROM similarly accesses a basic character font data file (FNTORG1, hereinafter abbreviated as basic character font) for storing a preset character font and a hash table FHASH1 stored in the RAM. A hash key file (HAKEY1) or the like that stores the data is stored.

  These data files unique to the present invention will be described in detail later. In addition to the above, in the RAM, a display message character string data file (MSG1) sent from the base station system BS10 through wireless communication and a character font in a format used by the display device LMon1 (for example, bitmap format) are expanded. The character font expansion data file (DDAT1), the operation parameter file (PARA1) storing parameters such as the start interval of the arithmetic processing unit of the microcomputer chip CPU1, and the sensing data file (SDAT1) storing data from the sensors Sen1 to 3 Stored. The ROM stores a control program code (PROG1) for the microcomputer chip CPU1.

  The microcomputer chip CPU1 includes a microcomputer chip serial bus signal line (SB), a microcomputer chip external interrupt signal line (INT), a microcomputer chip digital signal line (DP), a microcomputer connected to the built-in circuits such as the RAM, ROM, and SIO. Peripheral devices (RF1, LMon1, SW1, RTC1, Sen1, Sen2, Sen3, Buz1, LSC1) can be controlled by appropriately controlling the chip analog signal line (AP) by the microcomputer chip mounting program (PROG1) stored in the ROM. Control and realize sensing and wireless communication.

  For example, the serial bus signal line SB is controlled to exchange signal data with the wireless communication interface RF1. Further, as described later, data exchange with the real-time clock circuit RTC1 or the like is also realized. Further, the analog signal line AP is controlled and the analog-to-digital conversion circuit ADC reads the data of the analog type sensor. Further, the digital signal line DP is controlled via the programmable input / output circuit PIO to set each block of the circuit of the bracelet type sensor node SN1 to a desired operation mode, thereby realizing necessary operations and functions.

  In the bracelet type sensor node SN1, low power consumption is realized by a method called intermittent operation for the purpose of suppressing battery consumption. The intermittent operation is a technique for suppressing power consumption by starting a circuit at a certain interval, executing necessary operations such as sensing and wireless communication, and immediately shifting the circuit to a standby state after the operation is completed.

  For example, in the bracelet type sensor node SN1, it is sufficient to perform sensing typically at a time interval of about 5 minutes to 1 hour. On the other hand, the time required for sensing is, for example, several seconds at most even in pulse sensing that takes a relatively long time. For this reason, it is possible to reduce battery consumption as much as possible by cutting off the power supply to the wireless interface RF1 and the sensors Sen1 to 3 for most of the remaining time.

  In order to realize the intermittent operation, a timing signal, that is, a reference time signal for starting the arithmetic processing unit of the microcomputer chip CPU1 is indispensable. In the bracelet type sensor node SN1, the real-time clock circuit RTC1 generates a reference timing signal for intermittent operation. Specifically, the real-time clock circuit RTC1 generates a signal having a constant time period, and periodically interrupts the microcomputer chip via the microcomputer chip external interrupt signal line INT. This makes it possible to shift the microcomputer chip CPU1 to a complete standby state in a so-called software standby operation mode in which the clock X2 is stopped while retaining the contents of the registers and RAM in the microcomputer chip CPU1. With the above control, for example, the current consumption during standby can be suppressed to 1 μA or less. On the other hand, in order to respond to a parameter change request such as an activation time interval from the base station system BS10, it is necessary to be able to change the time period of the reference time signal. For this purpose, in the sensor node SN1, the real-time clock circuit RTC1 is connected to the serial bus signal line SB so that the time interval of the periodic signal of the RTC1 can be changed.

  Next, the radio communication interface RF1 converts sensor data sent from the microcomputer chip CPU1 via the serial bus signal line SB into a radio signal by a predetermined method, and transmits the radio signal to the base station system BS10 by radio. A radio signal is received from the base station system BS10. The base station system BS10 typically sends operation parameters such as a radio frequency channel and a transmission rate used for radio communication, and a text message to be displayed on the display device LMon1. Further, as a characteristic of the present invention, a character font necessary for display is also transmitted from the base station system BS10 by radio signals.

  The microcomputer chip CPU1 analyzes the contents of these signals and executes necessary processing. For example, in the case of an operation parameter, it is reflected in the setting for the next sensing or wireless communication. In the case of a display message, the character message is displayed on the display device LMon1 by a character display method unique to the present invention described later. In addition, in the bracelet type sensor node SN1, when the physical condition of the user US1 suddenly becomes abnormal by using a user interface switch SW1 described later, an emergency call is made by wireless communication in the base station system BS10 or the like. It is also possible to report to the user display system UC300.

The wireless communication interface RF1 is typically
(1) an oscillation circuit for generating a radio signal;
(2) modulation / demodulation circuit that converts a digital signal from a microcomputer chip into a radio signal;
(3) Wireless communication semiconductor integrated circuit (hereinafter abbreviated as RF chip) in which high-frequency amplifiers and the like are integrated on one chip.
Can be used. Although these details are not described, general ones can be used. Like the microcomputer chip CPU1, a clock is required for the operation, and the operation is performed by a clock signal generated by the crystal resonator X1. Further, in the present wireless communication interface RF1, for the purpose of suppressing current consumption during standby of intermittent operation, the crystal resonator X1 is stopped by a control signal from the microcomputer chip CPU1, and the entire RF chip is shifted to a standby state.

  In this case, the current consumption of the RF chip can be reduced to typically 1 μA or less. Further, the current consumption during standby can be further reduced by cutting off the power supply of the RF chip as necessary. Although omitted in FIG. 1, a matching circuit composed of passive components such as an inductor / capacitor is actually mounted for the purpose of impedance matching with the antenna ANT1.

  Next, the display device LMon1 is controlled by the microcomputer chip via the serial signal line SB, and displays graphics and characters according to requests from the base station system BS10 and the user display system UC300. Any character message can be displayed by using a character string display method and a character font data storage method unique to the present invention described later.

  FIG. 2 shows a configuration example of the display device LMon1. The display device LMon1 includes a monochrome type liquid crystal display LCD and an LCD controller (LCDC) that controls the LCD. The LCD controller LCDC is controlled by the microcomputer chip CPU1 via the serial bus signal line SB. By controlling the “0/1” level of the display control signal lines (RW1 and CL1) of the LCD according to the display request from the microcomputer chip CPU1, the “monochrome” of each dot (P00 to Pj0 in the figure) constituting the LCD is controlled. Can be controlled.

  By controlling an area composed of these dots (for example, an area of 16 × 16 dots) as a group of display areas (character display areas in the figure: GA10 to GA23), the characters to be displayed can be controlled. It is possible to display a text message to be transmitted to the user US1 wearing the bracelet type sensor node SN1.

  In order to display characters, a character font with a preset character code is required. In this sensor network, a message is transmitted using a preset character code (for example, shift JIS or the like). In order to prevent the display message from feeling uncomfortable within the range of normal daily life, a kanji font is also required. In general, in order to use Kanji fonts, 1020 characters are defined in the JIS first level and 3896 characters are defined in the JIS second level, so a ROM chip dedicated to Kanji fonts is necessary because it cannot be accommodated in the ROM of the microcomputer chip CPU1. . However, such a ROM chip cannot be mounted in the bracelet type sensor node SN1 due to cost and size restrictions. What solves this problem is a character display method and a character font storage method unique to the present invention described later.

  The display device LMon1 preferably has a low current consumption so that it can operate for a long time with the small battery BAT1. For this reason, a monochrome type LCD display device capable of displaying with low power consumption is suitable. In addition, too fine dots are inappropriate from the viewpoint of visibility and the like. Furthermore, since the size restriction is severe in the bracelet type sensor node SN1, typically, the display dot of about 32 × 64 dots (= 4 characters × 2 lines) is suitable for the entire display area. Furthermore, in order to realize low power consumption by intermittent operation, a type that can shift to a standby state is preferable when the user is not in use (for example, at bedtime). With the current technology, a type with a current consumption of 1 μA or less during standby can be obtained. In particular, an LCD unique to the present invention is unnecessary, and a general LCD can be used.

  Next, the user interface switch SW1 includes an emergency call switch (ESW1) provided below the display device LMon1 and a measurement start switch (GSW1) as shown in FIG. Signals from these switches are connected to the external interrupt signal line INT of the microcomputer chip CPU1 in FIG. 1, and an interrupt request can be generated to the microcomputer chip CPU1 by pressing these switches. As will be described later, when used in combination with the emergency call routine unique to the present invention, the response performance of the emergency call, that is, the response time is suppressed, and the power consumption is reduced to a level almost equal to that in the standby state. Things are possible.

  FIG. 3 is a front view of the bracelet type sensor node SN1 attached to the wrist (WRIST1) of the user US1. As shown in this figure, it is preferable from the viewpoint of operability and visibility to arrange the user interface switch SW1 (ESW1, GSW1) below the display device LMon1 on the paper.

  Next, the sensors Sen1 to 3 of the sensor node SN1 typically move the temperature sensor (Sen1) for acquiring the body temperature (skin temperature) of the user US1 wearing the bracelet type sensor node SN1 and the user US1. Or an acceleration sensor (Sen2) for acquiring an activity status such as whether the user is in a resting state, a pulse sensor (Sen3) for acquiring the health state of the user US1, or the like. Using the analog-digital conversion circuit ADC built in the microcomputer chip CPU1 via the analog signal line AP, the analog signals output by these sensors Sen1 to Sen3 are read by the microcomputer chip CPU1. For intermittent operation, it is necessary to shut off the power when these sensors are not used. For this purpose, the bracelet type sensor node has a configuration in which the power-off of these sensors can be controlled by the programmable input / output circuit PIO. That is, in the case of a sensor that consumes a small amount of current (˜5 μA) and can be directly supplied with power from the programmable input / output circuit PIO of the microcomputer chip CPU1, such as a temperature sensor, the power is turned on / off at the PIO of the microcomputer chip CPU1. Control off directly. On the other hand, when it is difficult to supply power directly from the programmable input / output circuit PIO of the microcomputer chip CPU1 with a current consumption on the order of several mA or more like a pulse sensor, the external power cut-off switch is controlled from the PIO. The power supply of these sensors is realized. As the power cut-off switch, a switch constituted by a Pch power MOSFET is suitable. Since it is not unique to the present invention, details are not described here.

  The pulse sensor Sen3 includes an infrared light emitting diode as a light emitting element, a phototransistor as a light receiving element, and an amplification circuit that amplifies a signal from the phototransistor to a predetermined level. In addition to the phototransistor, a photodiode can be used as the light receiving element.

  Next, the expansion connector CN1 includes a serial bus signal line SB, an external interrupt signal line INT, a digital signal line DP, an analog signal line AP, and a power supply line (VDD) that are not explicitly shown in the drawing. ) And a ground line (GND). Various sensors can be connected by connecting a sensor having an appropriate interface to this expansion connector. For example, a humidity sensor or the like can be connected. In addition, a reset signal line of the microcomputer chip CPU1 and a program rewrite signal line of the ROM of the microcomputer chip CPU1 can be added to the expansion connector as necessary. For example, by adding a reset signal line to the extension connector, it is possible to reset the microcomputer chip CPU1 from the outside. Alternatively, it can be forcibly reset when the program runs away. Similarly, by adding a program rewrite signal line of the microcomputer chip CPU1 to the expansion connector and combining it with a board having an appropriate interface and a program development tool, it is possible to realize a debugging or rewrite environment in the actual machine environment of the installed program. .

  In addition to the above, the LED display device LSC1 is controlled by the digital signal line DP of the microcomputer chip CPU1, and can be turned on / off by the ROM loading program of the microcomputer chip CPU1. Further, the buzzer Buz1 is also controlled by the digital signal line DP of the microcomputer chip CPU1, and the on / off of the buzzer Buz1 can be controlled by the ROM loading program of the microcomputer chip CPU1. It is possible to improve the visibility / convenience of the user interface by combining with the message display by the display device LMon1 (for example, sounding a buzzer when a character message is displayed or flashing the LED). It becomes.

<Configuration of base station system>
Next, the configuration of the base station system BS10 will be described with reference to FIG. The base station system BS10 includes an antenna (ANT10) and a wireless communication interface (RF10) that communicate with the sensor node SN1, a processor (CPU10) that performs arithmetic processing, a network interface (NI10) that communicates with the wide area network WAN10, It comprises a main memory (MEM10) and a secondary storage device (STR10) comprised of a storage device or the like.

  The base station system BS10 wirelessly communicates with the sensor node via the wireless interface RF10, and can communicate with the server system SV200 and the user display system UC300 located at a remote location via the network interface NI10. Specifically, the sensing data transmitted from the sensor nodes SN1 to SN30 by radio (WL1 to 30) is appropriately buffered, and the server system SV200 and the user display system UC300 via the wide area network WAN10 at an appropriate timing. Send sensing data to. Further, when a character message to be transmitted to the user US1 is sent from the user display system UC300, the message is buffered and transmitted to the sensor node SN1 wirelessly at an appropriate timing. An arbitrary character message can be displayed on the sensor node SN1 by causing the sensor node SN1 to download a character font wirelessly by a base station program unique to the present invention described later. As the secondary storage device STR10, typically, a hard disk or the like can be used. A solid disk such as a compact flash (registered trademark, the same applies hereinafter) can also be used. Further, a normal DRAM or the like can be used as the main memory.

  As will be described later, in order to realize a character display method and a character font data storage method unique to the present invention, a list of missing character fonts sent from the bracelet type sensor node SN1 on the main memory MEM10. A download request character font data file (FLIST10) is stored. In addition, character font data (FNT) is stored on the secondary storage device STR10 as a data file from which the character font data downloaded by the bracelet type sensor node SN1 is extracted.

  In addition to the above, the main memory MEM10 includes a sensor data buffer file (SDT) for buffering sensing data transmitted wirelessly from the bracelet type sensor node SN1, and the upper user display system UC300 and server system. Stored is a message data buffer file (MSGT) for buffering a character message or the like to be notified to the user US1 sent from the SV 200. Further, the secondary storage device STR10 stores a control program code (PROG10) in which a control program for the base station system BS10 is installed.

<Configuration of server system>
Next, the server system SV200 includes a processor (CPU200) that performs arithmetic processing, a network interface (NI200) that communicates with the wide area network WAN10, a main memory (MEM200) that stores programs to be executed, a storage device, and the like. And a secondary storage device (STR200) for storing sensing data and the like. A database (DB200) is constructed on the secondary storage device STR200, and sensor data (SDAT) sent via the base station system BS10 can be stored.

<Configuration of user display system>
Next, the user display system UC300 includes a processor (CPU300) that performs arithmetic processing, a network interface (NI300) that communicates with the wide area network WAN10, a main memory (MEM300) that stores programs to be executed, and a storage device And a secondary storage device (STR300) for storing data, a display device (DISP300) for displaying information to an administrator or an operator, and a user interface device (UI300) for receiving input. The user interface device UI300 typically includes a keyboard / mouse or the like. The display device DISP300 includes a CRT, a liquid crystal monitor, and the like. Using these devices, the activity status of the user US1 wearing the bracelet type sensor node SN1 and the health status such as the pulse are displayed, and the health status / activity status of the user can be checked. For example, if any abnormality occurs in the user US1, an appropriate character message (for example, “Mr. XX, are you okay?” Etc.) can be transmitted to the sensor node wearing user US1 via the network interface NI300. . Note that the user display system UC300, the server system SV200, and the base station system BS10 do not necessarily have to be geographically close as long as they are connected to the wide area network WAN10. That is, it is possible to display / check the activity status and health status of the user US1 even in a remote place.

  The above is the outline of the hardware configuration of the health management sensor network system (sensor network) according to the present invention.

<Details of sensor node software>
Hereinafter, the details of the installation program of the bracelet type sensor node SN1 will be described, and the character display method and character font data storage method unique to the present invention will be described.

  As described above, in the bracelet type sensor node SN1, it is impossible to mount a dedicated Kanji ROM chip with a built-in Kanji font due to cost / physical size / power consumption restrictions. For this reason, it is necessary to use a ROM and a RAM built in the microcomputer chip CPU1 on-chip as an area for mounting the character font.

On the other hand, the number of kanji characters used in daily life needs to be about 5000 characters (JIS first level: 1020 characters, second level: 3896 characters). That is, in order to store font data of these character data as a dot pattern of 16 × 16 dots for one character, a ROM having the following capacity is required.
5000 characters x 1 bit x 16 x 16 dots = 1280000 bits = 160KB
On the other hand, in the current semiconductor technology, the size of the ROM that can be embedded on-chip in the microcomputer chip CPU1 is about 128 KB at most.

  Furthermore, in the bracelet type sensor node SN1, since manufacturing cost is regarded as important, the usable microcomputer chip CPU1 is a low-cost type having a built-in ROM of about 32 KB. This trend is likely to remain even if semiconductor technology has advanced somewhat. Furthermore, since it is actually necessary to store program codes and the like in the ROM, the area usable as a built-in character font is about 16 KB (corresponding to 500 characters) at most. Furthermore, in addition to kanji, it is necessary to incorporate alphabets (= about 100 characters, lowercase letters) and hiragana / katakana (= 96 characters in total). For this reason, the number of Kanji characters that can be stored in the basic character font FNTORG1 of the on-chip ROM of the microcomputer chip CPU1 is about 250 after all.

  On the other hand, in the bracelet type sensor node SN1, the text message is “Are you okay?” When there is an abnormality in the pulse rate or when the emergency call button switch ESW1 is pressed, for example. (* Note XX is the name of the user US1) ”is used. In general, there are a wide variety of characters used for names and names. It is practically impossible to insert character font data covering all user names into the above 250 characters.

In order to solve this problem, the character font data that cannot be built into the ROM in the microcomputer chip CPU1 with the sensor node is simply downloaded from the base station system when necessary. However, it is necessary to determine what kind of character font is incorporated in the sensor node to which the character display message is sent and what kind of character font is not incorporated. For example, simply
(1) In the base station system, a table indicating what character fonts are incorporated in the sensor nodes under the control of the own station is held for all sensor nodes.
(2) When a character display message is sent, it is compared with the table of (1) to check whether the character code included in the message character string is mounted on the sensor node.
(3) The character font data which is not mounted (to the destination sensor node) is transmitted together with the character display message.
This method is also possible. However, in such a system, first, it is necessary to manage character fonts built in each sensor node in the base station system BS10. On the other hand, the bracelet type sensor node SN1 needs to be worn even when the user US1 is moving in the home, for example, to sense the pulse and other information. In general, a concrete wall in a room partition does not transmit radio waves, or even if it can transmit, the radio wave intensity is attenuated. For this reason, a plurality of base station systems BS10 may be required even in a normal home.

  Under such a use environment, there is a problem if the system simply manages the character font built in the sensor node as described above. That is, when a user moves and crosses between a plurality of base station systems BS, information about character fonts built in the corresponding sensor node must be exchanged between the base station systems BS.

  On the other hand, a method is also conceivable in which a font other than the basic character font built in the sensor node SN1 is always downloaded together with the character message to the sensor node every time. However, in such a method, since it is necessary to send font data wirelessly every time, there is a problem that the use efficiency of the wireless space is lowered, and the wireless communication time is increased, so the power consumption of the battery BAT1 is also increased. The very big problem of increasing will arise. Furthermore, under the general usage environment of the bracelet type sensor node SN1, the character that needs to be downloaded the most is the character used in the user's name. In other words, under a normal usage environment, once a user is decided, the character to be downloaded is typically fixed. That is, it is not necessary to download each time as described above as long as there is a mechanism that can retain the downloaded character font by an appropriate method.

What solves the above problems is a character display method and a character font data storage method unique to the present invention. The present invention
(1) High-speed judgment as to which character font data is installed on the sensor node side (2) Download only character font data that is not installed from the base station system (3) Downloaded character font Is characterized in that it is retained as long as there is a remaining area in the RAM. In particular, it is not necessary to manage complicated font data between the base station systems BS as described above, and frequently used character fonts such as user name character fonts need not be downloaded every time. . As a result, this is an excellent method that does not cause the use efficiency of the wireless space to be reduced by downloading fonts.

  Hereinafter, a method unique to the present invention will be described with reference to FIG. In the following drawings, an arrow drawn with a solid line represents a flow of processing, and an arrow drawn with a broken line represents a data flow.

  In the program PROG1 of the bracelet type sensor node SN1, after the power is turned on (P1), first, a node initialization routine (P100) is executed. FIG. 5 shows an example of a node initialization routine.

  In FIG. 5, first, a hardware initialization subroutine (P110) is executed. In the hardware initialization subroutine, the microcomputer chip CPU1 is initialized and various data files (FHASH1, FNTDL1, FLIST1, DDAT1, SDAT1, PARA1, etc.) unique to the present invention stored on the RAM are initialized (P111). ). When initializing the data file, the default values of the operation parameters stored in advance in the nonvolatile memory ROM are read and the contents are copied to the operation parameter file PARA1 secured in the RAM. The operation parameter file PARA1 typically stores a reference time signal for intermittent operation, a channel used in wireless communication, an operation parameter of the pulse sensor Sen3, and the like. Further, as will be described later, an area of the download character font FNDL1 is also secured on the RAM, and is initialized with a NULL pointer (pointer value is NULL). The pointer is the start address of the memory area where certain data is secured. In this embodiment, the pointer indicates the start address of the memory area in which the character font data is mounted. NULL indicates a state in which no data (address) is entered in the pointer.

  Next, the sensors Sen1 to 3 are set in an inactive state via the digital signal line of the microcomputer chip CPU1 so that the power supply to the sensors Sen1 to 3 is surely turned off (P112). Further, the display device LMon1 is also set in a standby state via the serial bus signal line SB (P113). Similarly, the real-time clock circuit RTC1 is accessed via the serial bus signal line SB, and RTC1 is initialized (P114). In the initialization of the real-time clock circuit RTC1, the content of the operation parameter file PARA1 created in P111 is read (PR1), and a reference for generating a time interval for shifting from the standby state to the operation state based on the information. Set the time interval.

  Next, a hash table FHASH1 creation subroutine (P120) is executed. In this subroutine, a character font hash table FHASH1, which is a main data file constituting the character display method and character font storage method unique to the present invention, is created on the RAM. Prior to the description of the procedure for creating the FHASH1 table, first, the configuration of these data files will be described.

  FIG. 6 shows the configuration of the character font hash table FHASH1 table, and the configuration of the downloaded character font FTDL1 stored in the RAM and the basic character font FNTORG1 stored in the ROM. Note that the basic character font FNTORG1 is already written in the data structure shown in FIG. 6 when compiling / writing the program PROG1 into the ROM, or separately using a writing tool to the built-in ROM of the microcomputer chip CPU1. To do.

  The character font data stored in the basic character font FTORG1 is frequently used as described above, such as alphabets, numbers, symbols (= 100 characters, uppercase and lowercase), hiragana / katakana (= 96 characters in total), etc. The minimum necessary character type is stored in a 16 dot × 16 dot bitmap format. That is, the basic character font FNTORG1 stores character font data of a small number of character types that are frequently used among character codes used in the sensor network. In this example, there are about 196 characters due to the alphabet, etc., and the file of the basic character font FNTORG1 has a capacity of about 6 Kbytes. As described above, in the one-chip type microcomputer chip CPU1 incorporating the 32 Kbyte ROM. A sufficient capacity for storing the program PROG1 and the like can be secured.

  Note that the writing method to the built-in ROM of the microcomputer chip CPU1 is not specific to the present invention, and therefore will not be described in detail here.

  As shown in FIG. 6, in the bracelet type sensor node SN1, the built-in character font is always called a hash value, and the character code of the character and the number of elements stored in the hash key file HAKEY1 stored in the ROM A character font hash table FHASH1 having a finite number of elements is classified according to a value uniquely determined from N. In other words, the character display method and character font storage method unique to the present invention always reads this character font corresponding to the character code to be displayed, or checks whether the character font is installed in the first place. The character font hash table is characterized by being accessed via the FHASH1 table.

  Here, the character code is an index value in a common character table (for example, shift JIS or the like) including a character when it is desired to display the character. Normally, a desired character font data is obtained by subtracting the character table using the character code as an index when accessing the table. There are a plurality of code systems, for example, “shift JIS code”, “JIS code”, “EUC code”, etc., depending on how the position of the character in the table is held. In the present invention, a “shift JIS code” (hereinafter abbreviated as “shift JIS”) is used unless otherwise specified in the following description. Shift JIS is a code system most often used when handling characters inside a personal computer or the like. The present invention is not affected by the character code table. The present invention is also applicable when other character code systems other than Shift JIS are used.

Various methods can be used to classify character data by character code hash value. For example, a method is possible in which character codes are classified by the remainder value obtained by dividing the character code by the number of elements (N) of the character font hash table FHASH1. By such a hash calculation method, it is possible to always map all characters to some element of the character font hash table FHASH1 (hereinafter referred to as the FHASH1 table). As an example, for example, when the number of elements is N = 16 (decimal), the character code “Hitachi” has a character code of 0x93FA (hexadecimal) in the shift JIS.
Index # of the FHASH1 table for "day" = remainder of dividing 0x93FA (hexadecimal) by 16 (decimal) = 10 (decimal)
And is mapped to the 10th area (# = 10) of the FHASH1 table. Similarly, “Stand” is character code 0x97A7 in Shift JIS.
"Standing" FHASH1 table index = remainder of dividing 0x97A7 by 16 = 7
And mapped to the seventh area (# = 7) of the FHASH1 table.

  The basic character font FNTORG1 on the ROM and the downloaded character font FTDL1 on the RAM are divided into a plurality of sections corresponding to the number of indexes # in the FHASH1 table, and each section is divided into the areas ROM0 to N-1 and the areas RAM0 to RAM0. N-1 is set. When searching for the target font, only the ROM area and RAM area of index # corresponding to the hash value (remainder) need be searched.

  In the FHASH1 table, the character data classified by the hash value as described above is stored in the memory area (= RAM or ROM area ROM0 to N on the ROM) in which the character font data corresponding to the character code belonging to the obtained hash value is stored. −1, RAM 0 to N−1), a pointer FNT_PR (= first memory address of the storage area) and a number of download characters (Size) that holds the number of download characters belonging to the hash value (FIG. 4). 6 FHASH1).

Of these, the memory area indicated by the font area pointer FNT_PR includes
(1) Character code of character font data (CODE)
(2) The substance of character font data, that is, each dot pattern (FDAT) for displaying the corresponding character on the display device LMon1
(3) Pointer to memory area where next character font data is stored (NXT)
Is stored.

  The memory area for storing character font data is divided into areas (partitions) corresponding to the number N of elements of the hash value, and N ROM areas (ROM0 to ROMN-1) corresponding to the index # of the FHASH1 table. ) And N RAM areas (RAM0 to N-1). The ROM area and the RAM area divided into N pieces are connected by a pointer NXT as shown in FIG. 6, for example, the ROM area RAM0 and the RAM area RAM0 are connected by a pointer NXT0k, and are virtually continuous areas. Can be treated as

  By adopting such a data structure, a so-called nest structure is employed so that it can flexibly cope with an increase in the number of characters to be stored due to downloading or the like. In other words, frequently used character font data is fixed in the ROM area, and the downloaded character font data is stored in the RAM area pointed to by the pointer NXT as necessary, so that each area is within the RAM capacity. Any number of character font data can be stored in the RAM 0 to N-1. At the end of this data structure, it is possible to express that no more character data exists as character data corresponding to the corresponding hash value by using the NXT pointer as a so-called NULL pointer (for example, FIG. (Refer to the NXT pointer in the data area starting from the address NXT2m + 1 in the 6 RAM2 area).

  That is, in the download character font FNDL1, a NULL pointer is set at a writable position (address) for each partition corresponding to the number N of elements of the hash value, and the NULL pointer of each partition indicates the write start position. Since the character font data has not yet been downloaded at the end of the initialization of the sensor node SN1, each area (0 to 1) is stored in each of the areas RAM0 to N-1 of the downloaded character font FNDL1 on the RAM of FIG. A NULL pointer is set for all the leading addresses of the areas RAM0 to N-1).

  Further, when storing the downloaded character font data, after storing the character font data, NULL is set to the pointer NXT following the character font data FDAT to set the end. That is, the new downloaded character font data is sequentially added to the end of each section.

  Then, the address of the newly stored character code is set in the pointer NXT of the character font data FDAT stored immediately before in the downloaded character font FNDL1. For example, in FIG. 6, when characters of the character code CODE32 and CODE33 are stored in the area RAM3 of the downloaded character font FNTDL1 which is a section of index # = 3, first, when the character font data FDAT32 of the character code CODE32 is first written. Is written at the position of the NULL pointer as in the area RAM 1 of FIG. Then, the pointer NXT at the end of the character font data FDAT32 is set to NULL. Next, when writing the character font data FDAT33 of the character code CODE33, the character code CODE33 and the character font data FDAT33 are written with the next address of the NULL pointer as the storage position, and the end pointer NXT is similarly set to the NULL pointer. .

  The character font data system unique to the present invention is characterized in that both ROM and RAM can be handled without particular distinction. For example, in the example of FIG. 6, the character code “CODE00”, the character code stored in the region represented by ROM0 of the basic character font FNTORG1 existing in the ROM is stored in the region ROM0 belonging to the hash value “0”. “CODE01”, character code “CODE02”. . . The character data composed of the character code “CODE0n” is stored. It should be noted that the character code CODE in this figure actually corresponds to the shift JIS code 0x93FA (corresponding to the character “day”), 0x97A7 (corresponding to the character “standing”), and the like. Further, as already described, the character font data FDAT includes “Monochrome” of the constituent dots P00 to Pjj when the character “date” or the character “standing” is displayed on the display device LMon1 shown in FIG. , That is, a dot pattern when “white” is “0” and “black” is “1” is stored.

  Then, the head address of the area RAM0 on the RAM corresponding to the hash value “0” is stored in the data pointer NXT0k of the data of CODE0n which is the end of the area ROM0. In area RAM0 of FIG. 6, since there is no downloaded character font data yet, NULL is set in address NXT0k, indicating that this is the end of the character font data corresponding to hash value “0”.

  The ROM area ROM1 and the RAM area RAM1 corresponding to the hash value “1” are the same as the ROM0 and RAM0. By setting a NULL pointer in the RAM area without ending with the ROM area, each hash value is set. The downloaded character font data can be stored in the RAM area.

  In the area belonging to the hash value “2”, the character code “CODE20”, the character code “CODE21”, the character code “CODE22”, etc. stored in the area represented by the ROM2 of the basic character font FNTORG1 on the ROM. . . In addition to the character data composed of the character font data corresponding to the character code “CODE2m”, the character code “CODE2m + 1” and the character code “CODE2m + 1” which are downloaded character fonts stored in the area represented by the RAM 2 on the RAM "Is stored. A NULL pointer is set to the pointer of the character code “CODE2m + 1” to indicate the end of the character font data corresponding to the hash value “2”.

  As shown in FIG. 6, as a method peculiar to the character font storage method of the present invention, the retained character font data is always terminated in the RAM area (the NXT pointer indicating the next character data storage area is NULL). There is a need to. In this method, character font data that is not stored in the basic character font FTORG1 secured in the ROM is downloaded and held in the download character font FTDL1 secured in the RAM area.

  For this reason, in order to handle the downloaded character font uniformly on the ROM and RAM in the FHASH1 table, it is necessary to register these new downloaded font areas in the area corresponding to the corresponding hash value. On the other hand, when registering character data, it is necessary to point to the area with an NXT pointer. That is, it is necessary to rewrite the NXT pointer, which has been NULL so far, to a pointer to an area in which newly downloaded character font data is registered. For this reason, the end of the character font area must be placed on the RAM.

In accordance with this data structure, for example, when checking whether or not a character font corresponding to a given character code is installed, the procedure is as follows.
(1) Referring to the number of elements N (for example, 16) from the hash key file HAKEY1, calculate a hash value corresponding to the character code of the character data to be checked. (2) Store character font data to be checked from the obtained hash value. (3) Take out the character code from the memory area pointed to by the pointer and check whether it corresponds to the given character code. If not, read the NXT pointer and execute (3) again.
(4) If the NXT pointer is a NULL pointer as a result of (3), it is determined that the character data corresponding to the given character code is not installed, that is, the basic character font FNTORG1 in the ROM or the RAM The processing for the character data can be executed without paying any attention to the difference between the downloaded character font FTDL1. As a result, there is a merit that the program structure is simplified and it becomes easy to perform testing and quality assurance.

  The reason why character fonts are managed in a format unique to the present invention as described above is as follows. First, as already described, this system is characterized in that it can handle character font data without being aware of the difference between ROM and RAM. Thereby, the program of sensor node SN1 can be simplified and maintainability improves. As a result, a simple and clear program structure with few bugs is realized.

  The second reason is that the hash table (FHASH1 table) can be used to speed up the search. As a result, it is checked whether the character font of the character code given on the sensor node side is installed. This is because a character display method peculiar to the present invention that only character fonts that are not present are downloaded from the base station system BS10 can be realized within a practical time.

Hereinafter, the effect of speeding up by the hash method will be described. In the above hash method, the search target is narrowed down, specifically, the character code of the search target can be narrowed down to subgroups classified by hash value, so the number of searches can be reduced, resulting in a reduction in search time. Is done. For example, in this embodiment, the average number of searches is
Average number of searches = total number of built-in character font data / N / 2 * N is reduced to the number of elements in the hash table. For this reason, it is possible to shorten the time required for searching whether there is font data corresponding to the corresponding character code by two digits or more when N = 16, for example. As a result, it is possible to search on the sensor node side whether the character font corresponding to the given character code is available within a practical time with the minimum memory resource. As a result, as described below, the base station system BS10 does not need to manage what character font each sensor node has. In other words, a character display system unique to the present invention, that is,
(1) Send the character code to the sensor node,
(2) Check if the corresponding character font is installed on the sensor node side,
(3) Request and download only character fonts that are not installed from the base station system.
This method can be executed within a practical time. That is, in particular, since it is not necessary to manage the fonts built in the subordinate sensor nodes SN1 to SN3 in the base station system BS10, it is possible to realize a sensor network system that can move between a plurality of base station systems without problems.

  Furthermore, since it is not necessary to download the character font data every time, there is no problem that the use efficiency of the wireless space is reduced and the power consumption of the battery BAT1 is increased.

  The configuration and characteristics of the character font data storage method unique to the present invention have been described above. Next, a description will be given of a routine for creating the FHASH1 table of P120 shown in FIG. In this hash table FHASH1 creation subroutine, the basic character font FNTORG1 is read, and then the FHASH1 table having the above data structure is created. The procedure will be described below with reference to FIG.

  First, the basic character font FNTORG1 is read, and the first memory address (pointer) of the character font data registered at the time of program compilation or writing into the ROM area is read (P121). Next, the registered character code is read from the memory address (P122). Next, the hash value calculation method (number of elements N, division, etc.) described in the hash key file HAKEY1 is applied to the read character code to obtain a hash value corresponding to the character code (P123). . Finally, the pointer read in P121 is registered in the corresponding hash value field (pointer FNT_PR) of the FHASH1 table (P124). Note that the Size field of the FHASH1 table is cleared to 0 (* Size is the number of downloaded character fonts in the RAM registered in the hash value element). Further, “NULL” is set in the address of the downloaded character font FNTDL1 on the RAM pointed to by the pointer NXT of the character font data at the end of the basic character font FTORG1. The above processing is repeated for all ROM areas (ROM 0 to N, FIG. 6) to complete the FHASH1 table.

  That is, in FIG. 6, the basic character font FTORG1 in ROM, which is the character font data storage area of the FHASH1 table, and the downloaded character font FNTDL1 in RAM are classified by the number N of elements read from the hash key file HAKEY1 stored in the ROM. The index # (number of partitions) to be determined is determined, and the fields of Size and pointer FNT_PR are set for each index # (0 to N-1).

  Then, by reading from the head of the basic character font FNTORG1 in the ROM area and obtaining a hash value from the character code, it is determined which partition (index #) the character code and character font data belong to. Since the pointer NXT of the character font data at the end of each partition points to the start address of the partition of the downloaded character font FNTDL1 on the RAM, it is initialized by setting NULL to this address. Further, the address of the character code read first is set in the pointer FNT_PR of the hash table FHASH1 as the head address of the partition. At the time of the initialization, character font data has not yet been written in the downloaded character font FNTDL1 on the RAM, so that all the sizes are set to 0. Through the above processing, the hash table FHASH1 for each partition is generated.

  In addition to the above processing, the content of the basic character font FNTORG1 on the ROM is fixed, and the hash key file HAKEY1 is also fixed on the ROM, so the number of elements N and the start address of each partition are also known. Therefore, the value of ADD0 to ADDN-1 of the basic character font FNTORG1, which is a known address, may be set in the pointer FNT_PR by a program.

  Next, the base station search subroutine (P130) shown in FIG. 5 is executed. In this subroutine, first, the clock of the RF chip (RF1) is raised (the power supply is also raised if necessary), and the RF chip RF1 is activated (P131). Next, the RF chip RF1 is set in a transmission state, and a base station search beacon signal is transmitted to the base station system BS10 to notify that it is powered on and can communicate (P132).

  Next, the RF chip RF1 is switched to the reception state, and a response from the base station system BS10 to the search beacon signal is awaited. When the response signal from the base station system BS10 is normally received, information such as the used radio channel is stored in the operation parameter file PARA1 (PW1).

  In the following wireless communication, the setting parameters of the operation parameter file PARA1 are used. If a response from the base station system BS10 is not received, the radio channel to be used is changed and executed again from the subroutine P132. Finally, the clock of the RF chip RF1 is stopped (the power is turned off as necessary) (P135), and the process proceeds to the next routine, the operation mode determination routine of FIG.

  When the node initialization routine P100 of FIG. 5 is completed, the operation mode determination routine (P200) of FIG. 4 is executed next. From this operation mode determination routine, a plurality of routines including a data detection routine (P300), a data transmission / reception routine (P400), and a standby transition routine (P510) can be executed (FIG. 4).

  In this routine, these three routines can be started as appropriate by the scheduler. Typically, intermittent operation is realized by starting each routine in the order of data detection routine P300 → data transmission / reception routine P400 → standby transition routine P510. The character display method unique to the present invention is started from the data transmission / reception routine P400. The activation order and the like can be changed by the operation parameter file PARA1. In the present embodiment, the description will focus on the parts specific to the present invention, and in the following embodiments, the description will be made in this activation order. However, the present invention is also applicable to cases other than this activation order.

  First, in the data detection routine P300, a sensor (Sen1 to 3) mounted on the bracelet type sensor node SN1 is activated according to a predetermined procedure to sense temperature / acceleration / pulse and the like. Since the individual sensing method is not particularly specific to the present invention, a detailed description thereof is omitted here. In this routine, first, the AD converter circuit ADC built in the microcomputer chip CPU1 necessary for sensing is activated, and then the sensor power supply is activated. The reason why the AD converter circuit ADC and the sensor power supply are activated is that, as already described, these peripheral circuits are normally set to the power-off state for the intermittent operation.

  When the AD conversion circuit ADC and the sensor power supply are started, the process waits until the outputs of the sensors Sen1 to Sen3 are stabilized, and then the data from the sensor is taken into the AD conversion circuit ADC. Further, necessary signal processing is performed on the data obtained from the AD conversion circuit ADC as necessary, and the result is written in the sensor data file SDAT1. For example, the optical pulse sensor Sen3 calculates a time difference between light intensity peaks from the obtained AD-converted data, and calculates a pulse rate per minute from the time difference information.

  When the sensing is completed, the power source of the AD conversion circuit ADC and the sensor power source are turned off, and the process returns to the operation mode determination routine P200.

  When the data detection routine P300 is completed by the above procedure, the data transmission / reception routine (P400) is started next. In this routine, the sensor data acquired in the data detection routine is transmitted to the base station system BS10, and in response to a request from the base station system BS10, a character display method and a character font data storage method unique to the present invention are set. The used message display routine (P800) is executed. Hereinafter, this routine will be described with reference to FIG.

  In this routine, first, in the sensor data transmission / reception subroutine (P420), the contents of the sensor data file SDAT1 are read and wirelessly transmitted to the base station system BS10. First, the sensor data SDAT1 is read and processed into a predetermined data format for wireless communication (P421). Typically, an error correction code or the like is added to the sensor data. After processing the data format for wireless communication, the RF chip RF1 is set to the transmission state, and the previous data is wirelessly transmitted (P422). After the wireless transmission is completed, the RF chip RF1 is set to the reception state and waits for an ACK signal to be transmitted from the base station system BS10 (P423). The ACK signal is a signal that is popular in wireless communication, and is a signal that is used for the purpose of confirming whether wirelessly transmitted data has arrived at a target destination without any problem.

  If the ACK signal is not transmitted from the base station system BS10 even after waiting for a certain time, the sensor data SDAT1 can be reliably delivered to the base station system BS10, for example, by transmitting again.

  Next, a command acquisition subroutine (P430) is executed. The command acquisition subroutine P430 is a subroutine for acquiring an operation request from the base station system BS10 to the node side such as a change in the operation parameter of the bracelet type sensor node SN1 or a text message display request.

  In this subroutine, first, the RF chip RF1 is switched to the transmission state, and a signal asking whether there is a command to be transmitted to the base station system BS10 is transmitted to the base station system BS10 (P431). Immediately after transmitting the inquiry signal, the RF chip RF1 is switched to the reception state, and the reception of the ACK signal is awaited (P432). In response to the inquiry, the base station system BS10 checks whether there is a command to be sent (= operation parameter change or message to be displayed), and puts a flag regarding whether there is a command to be sent in the ACK signal. And returns an ACK signal to the sensor node SN1. On the sensor node side, the ACK signal is analyzed, and if there is no command from the base station system, the process proceeds to P440, the clock of the RF chip RF1 is stopped, the power is turned off, and the operation mode determination routine is performed. Move to P200.

  On the other hand, if there is a command, the RF chip RF1 is continuously kept in a receiving state and waits for a command to be transmitted from the base station system BS10 (P433). Immediately after receiving the command, the RF chip RF1 is changed to the transmission state. An ACK signal indicating that the command has been successfully received is transmitted to the base station system BS10 (P434). Thereafter, the process proceeds to P440 and the present subroutine is exited. When the display message request is received at P433, the character string of the message to be displayed is written to the display message character string data file (MSG1) (DW2).

  The purpose of the command acquisition routine P430 is as follows. That is, in the bracelet type sensor node SN1, the RF chip RF1 is activated only when necessary, that is, only when the sensed sensor data is transmitted to the base station system BS10 in order to reduce power consumption (intermittent operation). On the other hand, there are cases where the base station system BS10 wants to change a sensor operation parameter, change a message of the display device LMon1, or transmit a request to the bracelet type sensor node SN1. These requests are normally transmitted from the user display system UC300 or the like to the base station system BS10 asynchronously with the activation interval of the bracelet type sensor node SN1. For example, as a result of the monitoring by the user display system UC300, an abnormal condition of the user US1 wearing the bracelet type sensor node SN1 is detected, and an inquiry message is transmitted to the wearing user of the bracelet type sensor node SN1. Is a typically assumed pattern. In this case, it is not necessarily guaranteed that the sensor node side is activated at the time when a request is transmitted from the user display system UC300 and is waiting in the reception state. On the other hand, if the sensor node side is kept in the receiving state without intermittent operation, it is guaranteed that the character display request from the user display system UC300 is surely transmitted to the sensor node side. However, as already described, in such a system, the battery BAT1 is consumed immediately and is not usable. In order to solve this problem, in this system, first, the base station system BS10 buffers a request such as a display message from the user display system UC300 and others to the sensor node SN1. When the corresponding sensor node SN1 transmits sensor data, it always inquires whether there is data to be downloaded to itself and always receives a necessary request. With this method, both low power consumption of the sensor node SN1 and response to requests from the user display system UC300 and the like are realized.

  If there is a command from the base station system BS10 after the end of the data transmission / reception routine P400, a command analysis routine (P450) is executed. In this routine, the signal transmitted from the base station system BS10 is analyzed (P451), and it is first determined whether the command is an operation parameter change request or a display message request to the display device LMon1.

  In the case of an operation parameter change request, the operation parameter file PARA1 is updated by the parameter setting subroutine (P452), and is reflected in the setting of sensing and wireless communication from the next time. On the other hand, in the case of a command such as a display message request, necessary processing is executed in a command execution subroutine (P700). After executing the necessary processing in this subroutine, the operation mode determination routine P200 is executed.

  The command execution subroutine P700 will be described below with reference to FIG. In this subroutine, as will be described below, a message display subroutine (P800), which is a character display method unique to the present invention, is executed. Prior to the execution of the message display subroutine P800, first, the contents of the request command are analyzed to determine what the command to be executed is, for example, a request to display a text message or a request to sound the buzzer Buz1. (P710).

  If the request is for the buzzer Buz1, after the buzzer is sounded in P720, the process proceeds to the operation determination mode routine P200. When displaying a character message, a message display subroutine P800 using a character display method unique to the present invention is started. Details of this subroutine will be described below.

  In this subroutine P800, first, regarding the character included in the character message given to the display message character string data file MSG1 in the character font search / readout subroutine (P810), the character font data corresponding to the character is sent to the sensor node SN1. Check whether it is installed in the ROM or RAM. At the same time, since it is necessary to develop and pass the character font data of the mounted character to the display device LMon1, the character font data is also read and prepared in this subroutine. Hereinafter, a specific processing flow will be described.

  First, the character string constituting the display message is read from the display message character string data file MSG1, and the character code of the character constituting the character string is acquired (P811). Next, the hash value corresponding to the character code is calculated from the character code and the calculation method (number of elements N, etc.) described in the hash key file HAKEY1 by the procedure already described (P812). Next, using the calculated hash value as an index, the FHASH1 table, which is a data storage method unique to the present invention, is accessed, and the memory areas ROM0 to N-1 and RAM0 to N0 in which the character codes are classified and stored. −1 head pointer FNT_PR (address) is acquired (P814). Thereafter, according to the procedure already described, the character codes stored in the memory areas ROM0 to N-1 and RAM0 to N-1 are compared with the given character codes (see P815, FIG. 6). If the character codes match, the font data FDAT is read from the character font data area.

  On the other hand, if the character code does not match and the NXT pointer becomes NULL, it is determined that the character is not mounted, and the character code is written in the request file FLIST1 (DW10). The above processing is executed for all the characters included in the display message character string data file MSG1, and all the character codes that need to be downloaded are written in the request file FLIST1 file.

  Finally, only for the installed characters, the character font data FDAT is written to a character font development data file (DDAT1), which is a display data file to be passed to the display device LMon1 (DW1). With the above procedure, the identification work of the character code that is not installed is completed.

  Thereafter, in the font download subroutine (P820), the base station system BS10 is requested to download character font data only for character fonts that are not installed. Hereinafter, the flow of processing will be described.

  In this subroutine, first, a character code that needs to be downloaded is read from the request file FLIST1 file and wirelessly transmitted to the base station system BS10 (P821). In the routine of this P821, as with the P421 subroutine already described, an error correction code, a header, etc. are attached and transmitted wirelessly. Next, it shifts to a reception standby state and waits for an ACK signal indicating that the request has been correctly received from the base station system BS10 (P822).

  If the ACK signal is not received even after waiting for a certain time, it is determined that the character font download request has not been successfully delivered to the base station system BS10 due to some trouble, and the character font download request is transmitted again. Next, when the ACK signal is received without any problem, it waits for the character font data to be transmitted while maintaining the reception state (P823).

  When the character font data is received, the download font registration subroutine (P840) is started, and the received character font data is registered in the already-described download character font FTDL1 unique to the present invention shown in FIG. Details of the download font registration subroutine will be described later. As described above, when the download font is registered, an ACK signal is transmitted to the base station system BS10 in order to notify the base station system BS10 that it has been registered without any problem (P824). If there are a plurality of character fonts to be downloaded and cannot be downloaded by one wireless communication, the above procedure is repeated as many times as necessary to download all necessary character font data. Finally, the character font data registered in the downloaded character font FNDL1 is read out and written in the character font development data file DDAT1, and the LMon1 data display subroutine (P830) is started. Prior to the description of the LMon1 data display routine, the download font registration subroutine P840 will be described.

  The download font registration subroutine P840 makes it possible to use the character font downloaded from the base station system BS10 in the subsequent character display, so that the download character font FNTDL1 (RAM0 to N-1) unique to the present invention shown in FIG. ) Is stored in the routine. By executing this routine, not only the current display message but also the corresponding characters can be displayed without the need for wireless download even in subsequent character display message requests. That is, it is possible to prevent the use efficiency of the wireless section from being deteriorated.

  Details of this subroutine will be described below. In this subroutine, first, the use size of the download character font FNDL1 secured on the RAM is calculated to check whether or not there is an empty space in the RAM (P841). As a result of the check, if the entire area of the RAM is used up or there is almost no remaining area, the RAM area of a necessary size is released by the FNTDL1 area release routine (P846). In P846, the RAM area is simply released from the beginning or end. In addition, for example, a method of adding a reference number field for each character font data and erasing from the smallest reference number is also possible. Various policies and algorithms are used to release the area, and there is no restriction that only a method peculiar to the present invention can be used, so details will not be described here. .

  In calculating the used area of the RAM, the size field of the FHASH1 table already described with reference to FIG. 6 is referred to, that is, the capacity of downloaded character font data (the number of characters Size is the capacity of the bitmap per character). The size of the used RAM area can be calculated at high speed by adding together the multiplied values. If the RAM size is not so abundant and it is desired to save the used RAM area as much as possible, the size of the used area can be increased by adding the sizes of the RAM 0 to N-1 areas without setting the Size field. It is also possible to calculate the RAM size.

  After the RAM area is secured by the above procedure, the character code of the downloaded character font data to be registered is read (P842), the hash value is calculated by the method already described (P843), and the RAM RAM is calculated from the result. A search is made as to which area above should be registered, and if necessary, a new area for storing the character font data entity is secured (P844) and registered in the area on the RAM (P845). When registering, the simplest is to connect to the end of the character font data area to which the NULL pointer is to be registered. Rewrite to pointer). However, it is not always necessary to connect the ends. The above processing is repeated for all downloaded characters, and this subroutine is completed.

  Hereinafter, the LMon1 data display routine will be described. In the LMon1 data display routine (P830), after activating the display device LMon1 from the standby state to the active state (P831), the contents of the character font development data file DDAT1 are read and transferred to the display device LMon1 (P832). Then, a message from the user display system UC300 and others is displayed. After the message is displayed, for example, the process is changed after waiting for the reaction of the user US1 (P833). For example, after waiting for whether or not the user interface switch SW1 is pressed, if a specific switch is pressed, the display device LMon1 is deactivated (P834), and the process proceeds to the operation mode determination subroutine P200. In this subroutine, the processing flow is simplified for the sake of explanation, but various processes other than waiting for a response from the user are possible. Since the processing is not particularly specific to the character display method and character data file storage method of the present invention, detailed description thereof is omitted here.

  The above is the details of the processing executed in the bracelet type sensor node SN1, and the character display method and character font data storage method unique to the present invention.

  Hereinafter, an emergency call routine (P600), which is another routine for starting the character display method P800 unique to the present invention, will be described. The emergency notification routine is a routine for executing an emergency call when the user US1 wearing the bracelet type sensor node SN1 becomes unwell. As already explained, it is necessary to exchange text messages with the user.

  Hereinafter, the flow of processing will be described with reference to FIG. In the emergency notification routine, first, a malfunction prevention subroutine (P610) is executed. The malfunction prevention subroutine is a routine for preventing erroneous calls due to erroneous pressing of the emergency call switch ESW1. Specifically, when an event of the emergency call switch ESW1 is detected, the system waits for a predetermined time, and typically, after a few seconds, the state of ESW1 is read again. If ESW1 is not kept pressed, it is determined that the switch has been erroneously pressed and the process returns to the standby state. If ESW1 is still pressed, it is officially recognized as an emergency call and the next emergency data transmission subroutine (P620) is executed.

  In this emergency data transmission subroutine, first, the RF chip RF1 is activated (P621). Next, emergency data to be transmitted to the base station system BS10 is created (P622). Next, the RF chip RF1 is set in a transmission state, and emergency data is transmitted (P623). Further, the RF chip RF1 is set in the reception state, and an ACK signal from the base station is waited to check whether or not the emergency call has surely reached the base station system BS10. If an ACK signal is not received even after a certain period of time, emergency data transmission is executed again. In this way, the emergency call is reliably transmitted to the base station system BS10. As shown in FIG. 8, if necessary, the message display routine P800 in which the character display method unique to the present invention described above is implemented is started via the P625 to P627 routines, and the base station system BS10. It is also possible to display a message such as “Are you okay?” On the display device LMon1.

  FIG. 9 shows an example of sensor data (SDT) of the sensor nodes SN1 to SN3 acquired by the base station system BS10 in the health management sensor network system described in the present embodiment.

  The sensor data acquired by the base station system BS10 is in the order of sensor ID (temperature, acceleration, pulse identifier), measurement value, time, etc. in each sensor node for each sensor node ID assigned in advance to the sensor nodes SN1 to SN3. Stored.

  Moreover, the flowchart of the control program of base station system BS10 is shown in FIGS. As shown in these drawings, also in the base station system BS10, a specific process is executed in order to realize a character display method specific to the present invention. Hereinafter, the flow of processing of the base station system BS10 will be described.

  First, in FIG. 10, in the base station system BS10, a task switching routine (P900) for switching a plurality of subroutines in a time-sharing manner with an internal timer or the like is executed. Unlike the sensor node, the base station system BS10 manages processor resources by an operating system, so-called OS, in the same way as a normal server or personal computer. This task switching routine is actually one of the functions provided by the OS. That is, it is possible to execute a program in which a plurality of routines operate in parallel without particular concern. Actually, these subroutines operate in a time-sharing manner in parallel with the task switching function of the OS built-in function (P900 in FIG. 10). In the present embodiment, this task switching routine also operates as a user program for the sake of simplicity. In this routine, a plurality of routines are sequentially switched according to a predetermined rule. Specifically, a radio interface subroutine (P930), a higher data reception subroutine (P920), and a higher data transmission subroutine (P910) are started. There are various known startup sequences and switching timings / methods of these subroutines, but they are not specific to the present invention. Therefore, here, for the sake of simplicity of explanation, the radio interface subroutine P930 is used. It is assumed that the upper data reception subroutine P920 and the upper data transmission subroutine P910 are switched in this order.

  Hereinafter, the radio interface subroutine P930 will be described. In this subroutine, data is exchanged with the sensor nodes SN1 to SN3 by wireless communication, and specific processing is executed in order to realize a character display method unique to the present invention. First, the wireless interface RF10 is set to the reception state and waits for a wireless signal from the sensor node to be transmitted (P931). Next, when a wireless signal is caught, data reception is performed, and further, the contents of the data are analyzed (P932). In the case of normal sensor data, the received sensor data is written to a sensor data buffer file (SDT). On the other hand, in the case of a character font data download request, the character code of the character data requested to be downloaded is written to the FLIST 10 which is a download request character font data file in the base station system BS10, and the font download subroutine (P940) is executed. to start. Further, in the case of a message or command request, a message transmission subroutine (P950) is started. Hereinafter, these subroutines will be described.

  In the font download subroutine P940, first, the download request character font data file FLIST10 file is read, and the character code that needs to be downloaded on the sensor node side is acquired (P941). Next, the character font data file (FNT) stored on the secondary storage device STR10 is read, and character font data corresponding to the character code read in the P941 routine is acquired (P942).

  Here, the character font data file FNT of the base station system BS10 holds a full set of character font data used for message transmission on the sensor network. For example, when Shift JIS is used as a character code as in this embodiment, the first level, the second level, and the like. In the same sensor network, the base station systems BS10, 20, and 30 hold the same character font data in the character font data file FNT.

  The above processing is repeated for necessary character codes, and character font data to be downloaded to the sensor nodes SN1 to SN3 is created. Next, the character font data to be downloaded is transmitted to the sensor node (P943). Next, the radio interface RF10 is switched to the reception state, and if the ACK signal from the sensor node SN1 can be received without any problem, the process is terminated (P944). If the ACK signal is not received within the specified time because the font data has not been successfully received, the character font data is transmitted again. As a result, it is possible to reliably download the font to the sensor node side.

  Next, in the message transmission subroutine P950, first, the message data buffer file (MSGT) is checked to check whether there is a display message request for the currently communicating sensor node (P951). As a result of the check, if there is no display message request for the sensor node, an ACK signal is simply transmitted to the sensor node, and the process is terminated. On the other hand, if there is a display message request, a flag signal indicating that there is data to be sent to the sensor node side is set in the ACK signal, and the ACK signal is transmitted (P952).

  Next, a display message request is transmitted to the sensor node (P953). Next, the wireless communication interface RF10 is switched to the reception state and waits for an ACK signal to be transmitted from the sensor node side. Similar to the font download subroutine P940, if the ACK signal is not received within the specified time because the display message request has not been successfully received, the character display message request is transmitted again. As a result, the display message request can be reliably delivered to the sensor node side.

  Next, the upper data reception subroutine P910 will be described with reference to FIG. This subroutine is transmitted, for example, from the user display system UC300 shown in FIG. 1, the server system SV200, or the like asynchronously with the intermittent operation intervals of the sensor nodes SN1 to SN3 via the network interface NI10 and the wide area network WAN10. This is a routine for storing the display message request in the message data buffer file MSGT. In order to achieve this function, first, it waits to receive a data signal from the network interface NI10 (P911). If the received data exists, the contents of the data are analyzed (P912), and the display message request is written to the message data buffer file MSGT (P913). Finally, the fact that the data reception has been normally completed is transmitted to the user display system UC300 or the server system SV200 that is the destination of the message request via the network interface NI10 and the wide area network WAN10. It is possible to improve the reliability of communication by inserting retransmission processing as necessary.

  Finally, the upper data transmission subroutine P920 will be described with reference to FIG. In this subroutine, sensor data transmitted intermittently from the sensor node is transmitted to the user display system UC300 and the server system SV200 shown in FIG. 1 via the network interface NI10 and the wide area network WAN10. It is a subroutine to send in. In order to achieve this function, in this subroutine, first, the sensor data buffer file SDT already described is read to check whether new sensor data is buffered (P921). If new sensor data is buffered, the sensor data is read (P922), and the sensor data is transmitted to, for example, the user display system UC300 via the network interface NI10 (P923). Note that the reliability of communication can be ensured by inserting a retransmission process as necessary.

  As described above, according to the present invention, in a sensor network that transmits a message using a preset character code, the one-chip microcomputer chip CPU 1 including a ROM and a RAM is required among the frequently used characters. If only the font data of the minimum character is stored in the ROM and the character font data to be displayed on the display device LMon1 of the sensor node SN1 is not in the ROM, even the normal character code is stored in the basic character font FNTORG1. For character font data that does not exist, the sensor node SN1 requests character font data required by the base station system BS10, downloads it, stores it in the RAM, and displays it. The microcomputer chip CPU1 of the sensor node SN1 While greatly reducing the number of characters stored in the ROM, Can always view the characters in Shin message is able promote production cost reduction and miniaturization / reduction in power consumption of the sensor node SN1 by eliminating the need for external ROM.

  The memory area (font data storage area) for storing the character font data of the microcomputer chip CPU1 includes the basic character font FNTORG1 provided in the ROM area and the downloaded character font FTDL1 provided in the RAM area with the number N of hash value elements. By dividing and connecting the divided N ROM areas and RAM areas with the pointer NXT, the two areas ROM0 to N-1 and the areas RAM0 to N-1 can be accessed as virtually continuous areas. it can.

  As a result, the presence / absence of the character font data to be used can be accessed in the 1 / N font data storage area corresponding to the hash value, so that the processing time can be reduced by reducing the search time (calculation time) of the microcomputer chip CPU1. And reduction in power consumption. Since the downloaded character font data is stored in the RAMs RAM0 to N-1 on the RAM and can be reused for the subsequent display, the base station system BS10 is compared with the case where the character font data is downloaded every time. The communication time with the sensor node SN1 can be greatly shortened, and the display process of the sensor node SN1 can be speeded up and the power consumption can be reduced.

  Further, since the download from the base station system BS10 only needs to be performed for character font data that the sensor node SN1 does not have, the communication time can be shortened, and the processing speed and power consumption can be reduced.

  Then, the character font data file FNT of the base station system BS10 holds a full set of character font data used in the sensor network, and requests only the characters required by the sensor nodes SN1 to SN3. This process can be simplified. Thereby, the base station system BS10 that communicates with the large number of sensor nodes SN1 to SN3, the user system UC300, and the server system SV200 does not need to manage the character font data of the sensor nodes SN1 to SN3. -3 can be applied to a sensor network that moves between a plurality of base station systems.

  Also, since the time required for downloading with the sensor nodes SN1 to SN3 is only insufficient character font data, communication is completed in a short time, the processing load of the base station system BS10 can be reduced, and the response speed is increased. it can.

  Further, the character font data data held by the sensor nodes SN1 to SN3 is character font data to be displayed in addition to the basic character font FNTORG1, and the conventional method in which the sensor nodes SN1 to SN3 hold a full set of character codes. In contrast, the entire sensor network can greatly reduce the memory capacity for storing character font data. For this reason, in the sensor network having a huge number of sensor nodes SN1, the memory capacity for storing the character font data can be reduced, and the manufacturing cost of the sensor nodes SN1 to SN3 can be reduced.

  Furthermore, after each sensor node SN1-3 performs intermittent operation and transmits sensor data to the base station system BS10, there is a message addressed to the corresponding sensor node, and the character font data included in the message is the sensor node SN1. Since the character font data is downloaded when it is not, the reduction in power consumption of the sensor node SN1 due to the intermittent operation can be maintained.

  In addition, since the bitmap format is adopted as the character font data FDAT, even when the microcomputer chip CPU1 having low processing capability is adopted, the character drawing data to be sent to the display device LMon1 can be easily developed, and the processing speed of the microcomputer chip CPU1 is increased. Can be achieved. Although it is possible to adopt a vector format as character font data, CPU power is required to generate drawing data, and power consumption tends to increase for display. For this reason, it is desirable to use a data format that can generate drawing data without adding complicated processing to the downloaded character font data.

  The character type stored in advance in the character font data stored in the basic character font FTORG1 determines the number of characters to be stored from the capacity that can be allocated to the areas RAM0 to N-1 in the ROM capacity, and the ROM stores within this number of characters. The basic character type to be stored may be determined.

  As described above, in the present invention, character font data is searched at a high speed and with a low load when displaying a message, and the minimum necessary character font data is downloaded from the base station system. The present invention can be applied to a sensor node provided with a display device and a sensor net provided with this sensor node.

The block diagram which shows the structure of the bracelet type | mold sensor node of the health management sensor network system to which this invention is applied, a base station system, a server system, and a user display system. The block diagram which shows the structure of the display apparatus of the bracelet type sensor node of this invention. The front view which shows the state which mounted | wore the wrist with the bracelet type sensor node of this invention. The flowchart which shows an example of the control program performed with the bracelet type sensor node of this invention. The flowchart which shows an example of the initialization process performed by P100 of FIG. The block diagram of the ROM area and RAM area which store the character font data of the bracelet type sensor node of this invention. 5 is a flowchart showing an example of command execution processing performed in P700 of FIG. The flowchart which shows an example of the emergency alert process performed by P600 of FIG. Explanatory drawing which shows an example of the sensor data of the sensor node acquired in the base station system of this invention. The flowchart which shows an example of the process performed with the base station system of this invention. The flowchart which shows an example of the high-order data transmission process performed by P910 of FIG. The flowchart which shows an example of the high-order data reception process performed by P920 of FIG.

Explanation of symbols

SN1 to 3 bracelet type sensor node CPU1 microcomputer chip RF1, RF10 wireless communication interface RAM CPU1 built-in random access memory ROM CPU1 built-in non-volatile memory FHASH1 built-in character font hash table FTORG1 basic character font data file FTDL1 download character font data file HAKEY1 hash key file PARA1 Operation parameter file MSG1 Display message character string data file FLIST1 Download request character font data file DDAT1 Character font expansion data file SDAT1 Sensing data file LMon1 Display device ESW1 Emergency switch GSW1 Measurement switch BAT1 Battery BS10, BS20, BS30 Base station Temu SV200 server system UC300 user display system

Claims (28)

A wireless communication circuit that transmits and receives to and from the base station;
A display device for displaying a message received by the wireless communication circuit based on a preset character code;
A control device for controlling the wireless communication circuit and the display device;
A battery for supplying power to the control device, a wireless communication circuit and a display device;
A wireless terminal device comprising:
The controller is
A character font data storage unit for storing character font data corresponding to the character code;
A font data search unit that acquires a character code from the received message and searches the character font data storage unit for character font data corresponding to the acquired character code;
As a result of the search, if there is no corresponding character font data in the character font data storage unit, the font data acquisition unit that requests the character font data from the base station and downloads the character font data from the base station;
A display pattern transfer unit that converts the character font data obtained by the search or download into drawing data and outputs the data to the display device;
With
The character font data storage unit
A wireless terminal device, wherein character font data of a character type having a high use frequency set in advance among the character codes is stored in advance. The character font data storage unit
It has a plurality of partitioned sections corresponding to the number of elements of the preset hash table,
The font data search unit
The hash value is obtained from the acquired character code, a partition corresponding to the hash value is acquired from the hash table, and character font data corresponding to the character code is searched in the partition. The wireless terminal device described. The character font data storage unit
ROM area that holds only the character font data of the preset frequently used character type;
A rewritable RAM area for storing the downloaded character font data;
The wireless terminal device according to claim 2, further comprising: The character font data storage unit
The wireless terminal device according to claim 3, further comprising a pointer that associates the end of the ROM area with the head of the RAM area for each of the partitions. Set NULL to the write start position of each partition of the RAM area,
The font data acquisition unit
The hash value is obtained from a character code of the acquired character font data, and the acquired character font data is stored in the NULL position in a RAM area of a partition corresponding to the hash value. 4. The wireless terminal device according to 4. The control device is composed of a one-chip type microcomputer including a ROM that holds stored contents and a RAM that can change the stored contents.
The ROM area for holding only the character font data of the frequently used character type set in advance is set in the ROM, and the RAM area for storing the downloaded character font data is set in the RAM. 3. The wireless terminal device according to 3. The font data search unit
4. The wireless terminal device according to claim 3, wherein after the ROM area is searched, the RAM area is searched if there is no corresponding character font data. The control device switches between a start state and a sleep state at a preset cycle,
The wireless terminal device according to claim 1, wherein information is measured from a sensor connected to the control device in the activated state, and the sensor information is transmitted to the base station. The controller is
The power supply to the wireless communication circuit and the display device can be supplied to the wireless communication circuit and the display device in the startup state, and the power supply to the wireless communication circuit and the display device is stopped in the sleep state. Wireless terminal device. A character data display method in a wireless terminal device comprising a control device for controlling a wireless communication circuit and a display device, and displaying characters on the display device based on a character code set in advance for a message received from a base station,
Obtaining a character code from the received message;
Searching the character font data corresponding to the acquired character code from the character font data storage unit that is stored in advance in the character font data of the character type having a high usage frequency provided in the control device in advance;
As a result of the search, if there is no corresponding character font data in the character font data storage unit, requesting the character font data from the base station, and downloading the character font data from the base station;
Converting the character font data obtained by the search or download into drawing data and outputting it to the display device;
A character data display method comprising: A step of setting a hash table that divides the character font data storage unit into a plurality of sections based on a preset number of elements at the time of initialization of the control device;
The step of searching from the character font data storage unit includes:
Obtaining a hash value based on the character code acquired from the message and the number of elements;
Obtaining the partition corresponding to the hash value from the hash table;
Searching for character font data corresponding to the character code in the section;
The character data display method according to claim 10, further comprising: The character font data storage unit
A ROM area that retains only the character font data of the preset frequently used character type, and a rewritable RAM area that stores the downloaded character font data;
The step of setting a hash table at the time of initialization of the control device includes:
A plurality of sections corresponding to the number of elements of the preset hash table are set in the ROM area and the RAM area,
The step of searching from the character font data storage unit includes:
12. The character data display method according to claim 11, wherein if there is no corresponding character font data after the ROM area is searched, the RAM area is searched. The character font data storage unit
A pointer that associates the end of the ROM area with the beginning of the RAM area for each partition,
The step of searching from the character font data storage unit includes:
13. The character data display method according to claim 12, wherein when the search target reaches the end of the ROM area in the section obtained from the hash table, the same data section in the RAM area indicated by the pointer is searched. The step of setting a hash table at the time of initialization of the control device includes:
Setting NULL to the write start position of each partition of the RAM area,
The step of downloading character font data from the base station comprises:
The hash value is obtained from the character code of the character font data acquired from the base station, and the acquired character code and character font data are stored at a NULL position in the RAM area corresponding to the partition corresponding to the hash value. The character data display method according to claim 13. The control device is composed of a one-chip type microcomputer including a ROM that holds stored contents and a RAM that can change the stored contents.
The step of setting a hash table at the time of initialization of the control device includes:
A ROM area that holds only the character font data of the preset frequently used character type is set in the ROM, a RAM area that stores the downloaded character font data is set in the RAM, and a ROM area of each section The character data display method according to claim 12, further comprising: setting a first address of the first address in the hash table, and setting NULL to a first address of a RAM area of each partition. Switching the control device between a start state and a sleep state at a preset period;
Measuring information from a sensor connected to the control device in the activated state;
Transmitting sensor information measured to the base station;
The character data display method according to claim 10, further comprising: The step of switching between the activated state and the hibernated state includes:
The power supply to the wireless communication circuit and the display device can be supplied to the wireless communication circuit and the display device in the activated state, while the power supply to the wireless communication circuit and the display device is stopped in the sleep state. Character data display method. A control device including a wireless communication circuit and a microcomputer for controlling the display device is provided, and a process for displaying characters on the display device based on a character code set in advance for a message received from a base station is executed on the microcomputer. A program to
Obtaining a character code from the received message;
A procedure for retrieving character font data corresponding to the acquired character code from a character font data storage unit that is stored in advance only in character font data of a frequently used character type provided in the control device in advance,
As a result of the search, if there is no corresponding character font data in the character font data storage unit, the character font data is requested from the base station, and the character font data is downloaded from the base station.
A procedure for converting the character font data obtained by the search or download into drawing data and outputting it to the display device;
Is executed by the microcomputer. A step of setting a hash table for dividing the character font data storage unit into a plurality of sections based on a preset number of elements at the time of initialization of the control device;
The procedure for searching from the character font data storage unit is as follows:
A procedure for obtaining a hash value based on the character code acquired from the message and the number of elements;
Obtaining the partition corresponding to the hash value from the hash table;
A procedure for searching for character font data corresponding to the character code in the section;
The program according to claim 18, comprising: The character font data storage unit
A ROM area that retains only the character font data of the preset frequently used character type, and a rewritable RAM area that stores the downloaded character font data;
The procedure for setting the hash table when initializing the control device is as follows:
A plurality of sections corresponding to the number of elements of the preset hash table are set in the ROM area and the RAM area,
The procedure for searching from the character font data storage unit is as follows:
20. The program according to claim 19, wherein after the ROM area is searched, the RAM area is searched if there is no corresponding character font data. The character font data storage unit
A pointer that associates the end of the ROM area with the beginning of the RAM area for each partition,
The procedure for searching from the character font data storage unit is as follows:
21. The program according to claim 20, wherein when the search target reaches the end of the ROM area in the partition acquired from the hash table, the program searches in the same partition of the RAM area pointed to by the pointer. The procedure for setting the hash table when initializing the control device is as follows:
Including the procedure of setting NULL to the write start position of each partition of the RAM area;
The procedure for downloading character font data from the base station is as follows:
The hash value is obtained from the character code of the character font data acquired from the base station, and the acquired character code and character font data are stored at a NULL position in the RAM area corresponding to the partition corresponding to the hash value. The program according to claim 21. The control device is composed of a one-chip type microcomputer including a ROM that holds stored contents and a RAM that can change the stored contents.
The procedure for setting the hash table when initializing the control device is as follows:
A ROM area that holds only the character font data of the preset frequently used character type is set in the ROM, a RAM area that stores the downloaded character font data is set in the RAM, and a ROM area of each section 21. The program according to claim 20, wherein the first address of the RAM is set in the hash table, and NULL is set as the first address of the RAM area of each partition. A procedure for switching the control device between a start state and a sleep state at a preset cycle;
A procedure for measuring information from a sensor connected to the control device in the activated state;
Transmitting the measured sensor information to the base station;
The program according to claim 18, further comprising: The procedure for switching between the activated state and the hibernated state is as follows:
25. The power supply to the wireless communication circuit and the display device can be supplied in the activated state, while the power supply to the wireless communication circuit and the display device is stopped in the idle state. Program. A wireless communication interface that transmits and receives data to and from the wireless terminal device;
A network interface for sending and receiving to and from the computer;
A control unit for transferring a message from the computer to the wireless terminal device;
A base station comprising:
The controller is
A message storage unit for storing a message addressed to the wireless terminal device received from the computer;
A font data storage unit for storing character font data corresponding to the character code and the character code set in advance in the message;
A message transfer unit that transmits a message retrieved from the message storage unit via the wireless communication interface when the wireless terminal device requests a message;
For only the character code requested from the wireless terminal device, the character font data providing unit for searching the corresponding character font data from the font data storage unit and transmitting from the wireless communication interface;
A base station characterized by comprising: A base station that relays a message addressed to a wireless terminal device received from a computer is a method of providing character font data to the wireless terminal device,
Receiving a message addressed to a wireless terminal device from the computer;
Holding the message until a request for the message is received from the wireless terminal device;
Transmitting the message when there is a message request from the wireless terminal device; and
When there is a request for transmission of character font data from the wireless terminal device, a step of transmitting only the corresponding character font data from the character font data corresponding to the character code and the character code set in advance to the wireless terminal device;
A method for providing character font data, comprising: A program for causing a computer that controls a base station that relays a message addressed to a wireless terminal device received from a computer to execute processing for providing character font data to the wireless terminal device,
A procedure for receiving a message addressed to a wireless terminal device from the computer;
A procedure for holding the message until a request for the message is received from the wireless terminal device;
A procedure for transmitting the message when a request for the message is received from the wireless terminal device;
A procedure of transmitting only character font data corresponding to a character code and a character code corresponding to the character code set in advance from the wireless terminal device to the wireless terminal device when a character font data transmission request is received from the wireless terminal device;
A program characterized by causing a computer to execute.

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