JP2006178579A - Microcomputer system using fuel cell as power source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microcomputer system capable of maintaining information, such as program execution states or process results, as much required under the power supply voltage supplied and maintained to the microcomputer system without saving information, such as program execution state or process results, at the time of power interruption in a non-volatile storage region or a storage region having a backup power source. <P>SOLUTION: By providing two series of fuel containers 250, 251 and controlling fuel supply to a generating part 202 by the two series of fuel containers even when a power interruption occurs, such as a power switch interruption or an unexpected power interruption, power supply to the microcomputer system is maintained as long as necessary. By arranging and constituting fuel supply to the generating part 202 by the second fuel container 251 as an auxiliary fuel container of the two series of fuel containers 250, 251 independently from a fuel interruption, problems caused by multiple interruptions of the power source are avoided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a microcomputer system using a fuel cell as a power supply source.

  In general, a microcomputer system includes a central processing unit (CPU), a read-only storage unit (ROM), a random access storage unit (RAM), an input / output control unit, a control program, a power supply unit, and the like. The microcomputer system has been widely developed as an electronic device for each application by adding a dedicated hardware unit to the microcomputer system and making the control program variable and dedicated program.

  In recent years, especially in portable and portable electronic devices, it is necessary to handle information such as characters, still images, moving images, and voices at high speed, in large quantities, and for a long time. There has been a demand for processing, large capacity of circuits and memories, power saving, long battery life and high output. Representative technologies that have made progress in response to these demands include high-speed processing technology such as improvement in the number of parallel processing bits in 32-bit CPUs, adoption of RISC architecture, multi-valued system-on-chip, flash memory, and composite memory There are large-capacity technologies such as mounting technology, power-saving technologies such as functional block control, operation mode control, sleep / suspend control, and event mode control, and power supply technologies such as lithium ion secondary batteries and non-contact power supply.

  In addition to the above lithium ion secondary batteries, primary batteries such as alkaline dry batteries and lithium batteries, and secondary batteries such as nickel-cadmium batteries and nickel metal hydride batteries are frequently used as means for supplying power to electronic devices composed of microcomputer systems. However, both have the problem of having to collect and process after use. Furthermore, a secondary battery requires a charger because it is used repeatedly for charging and discharging, and this is also a problem due to the time and electrical loss required for charging.

  Problems with power supply means in portable and portable electronic devices include improvement of battery energy density, resource saving, energy saving, and reduction of environmental load. Fuel cells are attracting attention as a technology for solving these problems in the future.

  In particular, as a fuel cell suitable for small electronic devices, it does not require a reformer, is easy to miniaturize, can operate at low temperatures, and uses liquid fuel, so it reacts directly with methanol. A direct methanol fuel cell (DMFC) that obtains an electromotive force by promising is promising. As shown in the operation principle diagram of FIG. 7, the DMFC includes a negative electrode, also called a fuel electrode and an air electrode, a positive electrode, and a solid polymer electrolyte membrane (PEM) that is a proton conductor. A mixed liquid of methanol and water is supplied to the negative electrode as a fuel, and an oxidation reaction shown in the chemical reaction formula shown below (Chemical Formula 1) occurs. In the positive electrode, oxygen in the air is taken in and an oxygen reduction reaction shown in the chemical reaction formula of the following (Chemical Formula 2) occurs. As a result of these reactions, an electromotive force is generated between the negative electrode and the positive electrode as shown in the following chemical reaction formula (Chemical Formula 3) and FIG. 7, and carbon dioxide gas and water are generated as by-products.

(Chemical formula 1)
Negative electrode: CH ₃ OH + H ₂ O → CO ₂ + 6H ⁺ + 6e ⁻
(Chemical formula 2)
Positive electrode: 3 / 2O ₂ + 6H ⁺ + 6e ⁻ → 3H ₂ O
(Chemical formula 3)
Total reaction: CH ₃ OH + 3 / 2O ₂ → CO ₂ + 2H ₂ O

  Conventionally, various systems and devices equipped with a fuel cell have been proposed. For example, in Patent Document 1 below, fuel cell power generation control that stabilizes the supply of power and can flexibly cope with diversification of equipment. The system configuration is shown. In this configuration, between the electronic device and the power generation device, device information is transmitted from the electronic device, and information such as the remaining fuel time is transmitted from the power generation device. To control.

  Further, Patent Document 2 below shows a configuration of a power supply system that can be directly connected to an electrode terminal of a predetermined electronic device, stably operate the electronic device, and can efficiently use power generation fuel. This configuration includes an electronic device and a power generation device (power generation module), the electronic device has a controller that transmits and receives control signals to and from the power generation device, and the power generation device includes two power generation units, a main power generation unit and a sub power generation unit A control unit for controlling This configuration basically attempts to optimally control the power supply by feeding back the fluctuation amount of the power supply voltage to the generated electronic device to the fuel supply amount to the power generation unit.

  In such an already proposed fuel cell system, a configuration and method relating to control as viewed from the fuel cell side are generally disclosed. However, control means and method relating to the operation of the microcomputer system, particularly in relation to its power supply. Is not fully disclosed. In order to meet demands for power saving, long time, long life, high output, etc. for portable and portable electronic devices, it is expected that the effect will be further enhanced by combining the above power saving technology and fuel cell. When viewed from the microcomputer side, the relationship with the power supply generally occurs and ends in different modes of operation at each stage of power activation, steady operation, standby operation, termination operation, and sudden unexpected power interruption. In particular, control against unexpected power interruption is an important technique for stable operation of portable and portable electronic devices.

  Now, in order to clarify the problem to be solved by the present invention, from the viewpoint of the prior art, power activation in a microcomputer system using a primary battery or a secondary battery typified by an alkaline dry battery or a lithium ion battery, The control means and method assumed in each stage of steady operation, standby operation, termination operation, and sudden unexpected power interruption will be described below with reference to FIG. It should be noted that the control means and method at each stage described above are assumed to be similar to those in the case of using a primary battery or a secondary battery in a microcomputer system employing a fuel cell.

  FIG. 8 shows an example of the operational relationship between the microcomputer system and the power supply. Hereinafter, in the present invention, the power control means and method shown in FIG. 8 are referred to as a conventional power control system.

  In the power-on operation (1), the microcomputer is in a reset state before the power switch is turned on, and after the power switch is turned on, the microcomputer is deactivated when the voltage of the power line is detected and becomes a specified value or more. The reset release state is entered by the reset signal to start execution of the first program. In other words, the microcomputer initializes its own state and shifts to a waiting state for activation factors such as commands in the microcomputer system, so-called standby operation (3). In general, the microcomputer externally interrupts one of two operations: power-on reset called power-on reset and subsequent reset release, and manual reset switch called manual reset and subsequent reset release. Detect and select the signal status.

  Steady operation (2) refers to a state of operation originally required for use of an electronic device. The microcomputer performs processing of commands input from the outside, transmission of the processing results to the outside, arithmetic processing inside the microcomputer, and the like. When these processes are completed, the microcomputer normally returns to the standby operation (3). Transition.

  When the microcomputer shifts to the standby operation (3), it executes a power saving operation mode such as sleep or standby, which is inherent to the microcomputer, while waiting for an activation factor such as an external command or an interrupt. The power saving operation mode is canceled by a power-on reset, a manual reset, or an interrupt signal (not shown).

  When a power switch shut-off event occurs in the end operation (4), generally the microcomputer system or electronic device is immediately reset. Also, in an example of the termination operation of a certain type of electronic device, when a power switch cut-off event occurs, the microcomputer is notified of the power cut-off state as an interrupt signal. Within a certain period, predetermined information such as the state of the microcomputer shown as “program end processing” in FIG. 8 is saved in a non-volatile storage area or a storage area having a backup power source, and the operation of the electronic device is ended. .

  Further, when a battery is replaced in an electronic device equipped with a conventional battery such as a primary battery or a secondary battery, the end operation and the start-up operation are generally performed in response to the occurrence of a battery empty warning, the preparation of a replacement battery, Power switch shut-off or electronic device operation lock, saving of program status and processing results by microcomputer inside electronic device, battery replacement, power switch reactivation or unlocking, return of program status and processing results, status before battery replacement To a series of battery replacement sequences for resuming use. Even in an electronic apparatus equipped with a fuel cell, the end operation and the start-up operation associated with the replacement of the fuel container are basically composed of a sequence similar to the above.

  Examples of unexpected power shutdown (5) include a case where a conventional battery or a fuel container is accidentally removed during operation of an electronic device, or a case where a power line or a fuel path is disconnected. In the event of an unexpected power shutdown (5), the voltage fluctuation of the power line is monitored, and an interrupt signal is generated to the microcomputer when it is outside the specified value range. The microcomputer recognizes this interrupt signal as an unexpected power-off, and information such as the program execution status and processing result is stored in a non-volatile manner as the highest priority interrupt processing within a period in which the power supply voltage is applied to the microcomputer itself. In preparation for a restart operation when power is restored, the operation of the electronic device is terminated.

JP 2003-115313 A JP 2002-280035 A

  In summary, the conventional power control method is classified into the following three operations. That is, the first operation monitors the voltage fluctuation of the power supply line and identifies the fluctuation factor, and the second operation performs normal operation such as steady operation or standby operation if the monitored value is within the specified value range. The third operation is to perform processing according to the variation factor as an exceptional operation if the monitored value is outside the specified value range. In the third operation, time securing means for maintaining the supply voltage to the microcomputer for a specified time, and information such as the program execution state and processing result of the microcomputer within the secured time are stored in the nonvolatile storage area and the backup power source. Means for evacuating to a storage area provided with

  In such a conventional power supply control system, the microcomputer receives the fluctuation information of the output voltage of the power supply unit from the normal power supply monitoring element, and performs processing corresponding to the fluctuation factor. The fluctuation factors include turning on and off the power switch, etc. The microcomputer identifies these fluctuation factors, and if the output voltage of the power supply section is increasing, start processing, that is, after setting the microcomputer system state to the initial value The execution of the program is started, or the program execution state is resumed by restoring information such as the program execution state and the processing result. On the other hand, the microcomputer terminates the operation if the output voltage of the power supply section is decreasing, or stores the program execution state and processing result as a process of unexpected power shut-off with a non-volatile storage area and a backup power supply. After executing the process for saving to the area, the operation is terminated. In general, such a power supply control method requires means for securing time for saving information such as the program execution state of the microcomputer and processing results to a nonvolatile storage area or a storage area having a backup power supply. It is done. If the above monitoring value is outside the allowable value, the reset signal must be deactivated with a sufficient time delay to ensure the save time, and the microcomputer system must be operated stably. For this reason, for example, in the case of an unexpected power shutdown, the amount of information such as the program execution state and processing result of the microcomputer that can be saved is the delay time of the reset signal that can be secured and the supply voltage of the microcomputer that can operate stably There is a problem that it must be determined in consideration of the maintenance time.

  As a further problem of the conventional power supply control method, there is a method for coping with multiple interruptions of the power supply. That is, a period during which the microcomputer saves information such as the program execution state and processing results to a nonvolatile storage area or a storage area equipped with a backup power source while a power supply voltage that can be operated is detected and the power supply is applied In addition, there is a problem of a method for effectively dealing with the case where the supply voltage cannot be maintained for some reason. There is a method of using a plurality of power supplies and switching in response to multiple interruption, but this is not a method suitable for a portable or portable electronic device.

  An object of the present invention is to provide a microcomputer system including a fuel cell power generation unit and a microcomputer and a method for controlling the power supply in order to meet the above-described problems in the conventional power supply control system.

  In order to achieve the above object, a microcomputer system according to the present invention includes an input / output device having an interface function with the outside, a processing unit for executing programs and processing data, a storage unit for storing programs and data, A microcomputer system comprising: a microcomputer unit including an input / output control unit that transmits and receives data and control signals to and from an entry output device; and a power supply unit that supplies power to the system, wherein the power supply unit A power generation unit comprising a fuel cell, a power supply control unit having a control function for the microcomputer unit, a first fuel container for supplying fuel to the power generation unit when main power is supplied into the system, and the system A second fuel for supplying fuel to the power generation unit when auxiliary power is supplied The first fuel in response to an activation operation, a steady operation, a standby operation, an end operation, or an emergency operation for an unexpected power interruption executed by the microcomputer unit. Each fuel supply from the container and the second fuel container is controlled.

  That is, in the microcomputer system according to the present invention, two series of fuel containers are provided, and even when a power shut-off event such as a power switch shut-off or an unexpected power shut-off occurs, By controlling the fuel supply, as much power supply as necessary to the microcomputer system is maintained.

  Furthermore, in order to solve the above-described problems, the microcomputer system according to the present invention saves information such as a program execution state and a processing result in power shutdown in a storage area having a nonvolatile storage area or a backup power source, That is, as many programs as necessary under the power supply voltage supplied and maintained in the microcomputer system by controlling the fuel supply to the power generation unit by the two series of fuel containers without moving the information on the storage unit. It is characterized by holding information such as execution status and processing result.

  Furthermore, the microcomputer system according to the present invention is arranged and configured so that the fuel supply to the power generation unit by the second fuel container, which is the auxiliary fuel container, is independent from the fuel shut-off, in the two series of fuel containers. It is characterized by avoiding a problem that occurs with respect to multiple shutoff of power supplies.

  According to the microcomputer system of the present invention, information to be stored and restored such as the program execution state and processing result of the microcomputer in the start (turn-on), shut-off (stop), multiple shut-off, etc. of the power source in the microcomputer system is nonvolatile. Therefore, it is not necessary to save to a storage area having a volatile storage area or a backup power supply, and therefore it is not necessary to secure time and the number of clocks required for saving and restoring the information, and the system configuration can be simplified.

  Furthermore, according to the microcomputer system of the present invention, a microcomputer and a system-on-chip integrated circuit element can be configured without using a nonvolatile memory, so that the integrated circuit manufacturing process can be simplified.

  Furthermore, the microcomputer system according to the present invention does not require a primary battery for operation and a secondary battery as a backup power source for primary storage and storage of information in the microcomputer system. The need for recovery and charger can be avoided, contributing to resource saving, energy saving and environmental load reduction.

  Hereinafter, an embodiment of a microcomputer system according to the present invention (hereinafter referred to as “the present invention system” as appropriate) will be described with reference to the drawings. Note that the present invention is not limited by the description.

   FIG. 1 is a conceptual diagram of a portable electronic thermometer which is an embodiment of a microcomputer system operating with a fuel cell. In FIG. 1, the portable electronic thermometer 10 includes a liquid crystal display unit 12 including a liquid crystal panel, a key input unit 14 including a button switch, and a sensor input unit including a temperature sensor. This is because this is a typical electronic device constituted by the system (not shown) of the present invention in which 16, the power switch 13, the reset switch 15, and the fuel container 11 are detachably provided. However, the object of the present invention is to solve the above-mentioned problems of the conventional power supply control system in the microcomputer system, to provide the fuel supply to the power generation unit including the two series of fuel containers, and to start the power supply. The display unit 12, the digital input unit 14, and the analog input that depart from the essence of the present invention are solved by adaptively controlling each stage of steady operation, standby operation, termination operation, and unexpected power-off. The description of the operation related to the unit 16 is omitted.

  FIG. 2 is an overall configuration diagram of the system of the present invention. The system of the present invention includes a microcomputer unit 100 having a control function for the entire system, a power supply unit 200 having a power supply control function for the entire system, and fuel used in the power generation unit when main power is supplied to the entire system. It consists of four blocks of a first fuel container 250 for supply and an input / output device 300 used for a man-machine interface.

  The microcomputer unit 100 and the power supply unit 200 are interfaced by one or a plurality of power supply unit control input signals 101 and power supply unit control output signals 102, respectively, and the microcomputer unit 100 and the input / output device 300 are respectively connected by one. The input / output device control input signal 132 and the input / output device control output signal 131 are interfaced. The microcomputer unit 100 and the input / output device 300 are supplied with the power supply voltage generated by the power supply unit 200 through one or a plurality of power supply lines 210. In the system of the present invention, fuel is supplied from the first fuel container 250 to the power supply unit 200 through the fuel path 211.

  FIG. 3 shows a configuration of the microcomputer unit 100. The microcomputer unit 100 includes a processing unit 110, a storage unit 120, and an input / output control unit 130 as its components. The main functions of the microcomputer unit 100 are a program execution and data processing function in the processing unit 110, a program and data storage control function in the storage unit 120, an interface function with an input / output device in the input / output control unit 130, and a power source. This is a mutual control function related to the power supply with the unit 200.

  The processing unit 110 includes a CPU unit 111 and another logic unit 112 including functional units other than the CPU unit 111. The other logic unit 112 includes, for example, a clock generator, an interrupt control circuit, an address decoder, and the like. It is. A power unit control input signal 101 is input from the power unit 200 to the processing unit 110, and a power unit control output signal 102 is output from the processing unit 110 to the power unit 200.

  The power supply unit control input signal 101 includes a reset signal and an interrupt request signal for the CPU unit 111. The power supply unit control output signal 102 includes information indicating a power supply abnormality and information indicating a shift to a low power process such as a sleep operation and a return from the low power process. The power supply abnormality is detected by monitoring the voltage value of the power supply line 210 in at least one of the power supply unit 200, the microcomputer unit 100, and the input / output device 300.

  The storage unit 120 includes a ROM unit 121 composed of a read-only memory (ROM) and a RAM unit 122 composed of a readable / writable memory (RAM) as components. In a general application example, a mask ROM is used as the ROM unit 121, and fixed programs and fixed data corresponding to various application examples are burned into the mask ROM in a process of manufacturing as a semiconductor element including the microcomputer unit 100. . In the RAM unit 122, information such as variable programs to be changed in the microcomputer system, additional programs and data fetched from the input / output device, program execution results, and primary storage data are arranged. In the present embodiment, a static RAM capable of holding write information when the clock is stopped in a power supply state is used for the RAM unit 122. The feature of the system of the present invention is that it is possible to construct a microcomputer system and an electronic device without adopting a permanent or temporary storage means for programs and data by a conventional non-volatile memory and a conventional battery. is there.

  The input / output control unit 130 interfaces with the input / output device 300 by one or more input / output device control input signals 132 and input / output device control output signals 131. More specifically, the input control unit 134 that takes in the button switch information and the like from the input / output device 300 as part of the input / output device control input signal 132, and the display information on the liquid crystal panel unit is input / output device control. The output control unit 133 that outputs as the output signal 131 and the information from the analog input unit 16 described above are taken in as another part of the input / output device control input signal 132 and are converted into an analog / digital converter inside the input / output control unit 130. An analog input control unit (not shown) having (ADC) is a main component. The input / output control unit 130 may include a bidirectional control unit and an analog output control unit inside depending on the application of the system of the present invention.

  In the portable electronic device, the input / output device 300 includes components related to a man-machine interface, and includes a liquid crystal display unit 12, a key input unit 14, and a sensor input unit 16 in the present embodiment.

  FIG. 4 shows the configuration of the power supply unit 200. The power supply unit 200 includes a power supply control unit 201, a power generation unit 202, a supply control unit 203, and a second fuel container 251 as main components. Here, components other than the power control unit 201 including the power generation unit 202, the supply control unit 203, and the second fuel container 251 control fuel paths 211, 212, and 213, which will be described later, and path formation between these fuel paths. A mechanical mechanism is included in a part of the supply control unit 203. The main function of the power supply unit 200 is a power generation function. Furthermore, a mutual control function related to power supply to the microcomputer unit 100 in the power supply control unit 201 and a supply switching control function of two fuel containers are provided for the power generation function. Provided as an auxiliary function.

  The power generation unit 202 is a direct methanol fuel cell power generator using methanol having the configuration shown in FIG. In FIG. 7, the voltage generated by the power generation unit 202 is extracted from between a positive electrode and a negative electrode, which are also referred to as an air electrode and a fuel electrode, respectively, and is supplied to the output circuit 205 through the power line 214. The supply control unit 203 is coupled to the first fuel container 250 outside the power supply unit 200 by the fuel path 211, coupled to the second fuel container 251 by the fuel path 212, and coupled to the power generation unit 202 by the fuel path 213. Yes. The supply control unit 203 connects one of the fuel path 211 and the fuel path 212 to the fuel path 213 under the control of the control unit 204. Further, as another function of the supply control unit 203, the fuel path 211 and the fuel path 212 are connected under the control of the control unit 204. The other function is used to fill the fuel from the first fuel container 250 to the second fuel container 251 when the first fuel container 250 is attached to the power supply unit 200.

  The power supply control unit 201 includes a control unit 204, an output circuit 205, a detection unit 206, a determination unit 207, and a notification unit 208 as its components. The output circuit 205 boosts the input voltage supplied from the power generation unit 202 via the power supply line 214 and applies a conversion operation such as time adjustment and shaping, and then to one or more power supply lines 210 and the power supply line 215. Output. The power supply line 210 is used for the power supply of the microcomputer unit 100 and the input / output device 300, and the power supply line 215 is used for the internal power supply of the power supply unit 200. The control means 204 controls the connection of the fuel paths in the supply control unit 203 by the control output signal 221 and can know the state of the fuel path controlled by the above-described supply control unit 203 by the control input signal 220. Further, the control unit 204 has a control input signal 222 and a control output signal 223 of the power supply control unit 201. The control input signal 222 and the control output signal 223 are used as a control input signal and a control output signal for the output circuit 205 and the detection unit 206. Based on the control output signal 223, the detection means 206 takes in the status notification signal 102 from the processing unit 110, the status notification signal 224 of the first fuel container 250, the power switch signal 225 indicating the status of the power switch 13 and the reset switch 15, and The captured signal is selected and output as the detection means output signal 226. The determination unit 207 takes in the detection unit output signal 226 and outputs the determination result as the determination unit output signal 227. The notification unit 208 takes in the determination unit output signal 227 and applies a conversion operation such as time adjustment and shaping as a notification signal of the identification information of the operation that the CPU unit 111 must respond according to the state of the power supply. One or more power supply unit control input signals 101 are output to the processing unit 110.

  The power supply unit control output signal 102 for notifying the state from the processing unit 110 includes information for notifying a power supply abnormality and information indicating a shift to a low power process including a sleep operation and a return from the low power process. .

  The startup power supply 216 functions as a startup voltage of the power supply unit 200, and the power supply selection unit 209 selects either the power supply line 215 or the startup power supply 216 and outputs it as the power supply internal voltage line 217 of the power supply control unit 201.

  Next, the operation between the microcomputer unit 100 and the power supply unit 200 will be described. FIG. 5 is a flowchart showing the overall operation flow of the system of the present invention. The main routine S10 comprises an initialization routine S11, a standby state process S15, and a steady state process S14.

  The processing unit 110 applies a power supply unit control input after a predetermined power supply voltage is applied from the output circuit 205 to the processing unit 110, the storage unit 120, the input / output control unit 130, and the input / output device 300 via the power line 210. When the reset signal forming a part of the signal 101 is deactivated, the reset is released and the initialization routine S11 is executed. The initialization routine S11 includes a program group (not shown) for initial setting of the condition code register in the CPU unit 111, the state of the RAM unit 122, the state of the internal register of the input / output control unit 130, and the like. The initialization routine S11 includes a program for displaying a command waiting prompt on the liquid crystal display unit 12 in the electronic apparatus shown in FIG.

  After executing the initialization routine S11, the processing unit 110 shifts to a waiting state for an activation factor such as an external command, that is, a standby state S12. If there is an external command from the key input unit 14 or the sensor input unit 16 in the standby state S12, the processing unit 110 executes the corresponding external command processing S14 and then shifts to the standby state S12 again. In the standby state S12, the processing unit 110 uses a power saving operation mode such as sleep or standby that is inherent to the CPU unit 111, and proceeds to the first low power processing S15 that is released from the power saving operation mode by an external command. To do.

  FIG. 6 is a flowchart showing an operation flow of external interrupt processing. External interrupt factors in the system of the present invention include detection of a power supply abnormality related to unexpected power interruption, power-on switch related to the power switch 13 and reset switch 15, and external key input related to the key input unit 14 and sensor input unit 16. And a fuel container mounting for attaching and detaching the first fuel container 250. Among the above external interrupt factors, power failure detection, power switch on, and fuel container installation related to unexpected power shutoff are events that occur in the power supply unit 100, and an interrupt event is generated by the power supply unit control input signal 101 to the processing unit 100. Occurrence is notified. Among the above external interrupt factors, external key input is an event that occurs in the input / output device 300, and an interrupt event occurs (not shown) via the internal interrupt control line via the input / output control unit 130 to the normal processing unit 110. Be notified.

  In the external interrupt process S20, the CPU unit 111 analyzes the interrupt factor and executes a corresponding process. That is, if the power switch is turned on S21 is shut off (N), then the state of the fuel container mounting S22 is checked, and if the state of the fuel container mounting S22 is removed (N), the steady termination process S25 is executed. The operation of the electronic device is then terminated (S26). On the other hand, if the state of the fuel container mounting S22 is mounting (Y), after executing the program state storage processing S23, the second low power processing S24 is executed. In the second low power processing S24, the CPU 111 outputs a power unit control output signal 102 to the power unit 200 as a notification signal for entering the second low power processing. The power supply unit 200 receives the power supply unit control output signal 102 and uses it as a start signal to control the supply control unit 203 by the control means 204 to switch the fuel supply of the power generation unit from the first fuel container 250 to the second fuel container 251. .

  The system according to the present invention allows program execution to be resumed in the program state saving process S23 without saving the state during execution of the program to a non-volatile storage area or a storage area equipped with a backup power supply as in the conventional power control method. In order to maintain the minimum information, a fuel supply switching control signal is output from the microcomputer side to the power source side.

  If the state of power switch on S21 is on (Y), the state of power failure detection S27 is examined. The normal power supply abnormality is detected by monitoring the voltage of the power supply line 210. If the state of the power supply abnormality detection S27 is detected (Y), the CPU 111 shifts the process to the program state storage process S23. If the power supply abnormality detection S27 is not detected (N), the CPU 111 checks the external key input state in S28. If the state of the external key input is present (Y), the CPU unit 111 executes a return process from the first low power process S15 in the standby state in S29. If there is no external key input state (N), the CPU 111 checks the mounting state of the first fuel container in S30. If the mounted state of the first fuel container 250 is removed (N) in S30, this is recognized as fuel replacement, and the CPU 111 proceeds to program state saving processing S23. If the mounting state of the first fuel container 250 is mounting (Y) in S30, the CPU unit 111 proceeds to return processing S31 from the second low power processing. In S <b> 31, the CPU unit 111 outputs the power supply unit control output signal 102 to the power supply unit 200 as a notification signal for returning from the second low power processing. The power supply unit 200 receives the power supply unit control output signal 102, and controls the supply control unit 203 by the control means 204 using this as an activation signal, and switches the fuel supply of the power generation unit 202 from the second fuel container 251 to the first fuel container 250. .

  In the system of the present invention, a configuration in which the power generation unit 202 constantly generates power by preparing two series of fuel containers 250 and 251 is employed, so that the problem of multiple shutoff in the conventional power control method can be avoided.

  With the configuration and method described above, information such as the program execution status and processing results of the microcomputer in starting (turning on), shutting down (stopping), and shutting down multiple power sources in the electronic device (microcomputer system) is stored in the nonvolatile storage area and Various problems caused by saving to a storage area having a backup power source can be solved.

  The present invention aims to provide a microcomputer system comprising a fuel cell power generation unit and a microcomputer and a method for controlling the power supply in order to meet the above-mentioned problems in the conventional power supply control system. It is another object of the present invention to provide a general power supply control method for an electronic device equipped with a battery. In the above-described embodiment, the case where a direct methanol fuel cell type fuel cell is used for the power generation unit 202 has been described. However, the essence of the present invention is to start (turn on) or shut off (stop) the power supply in the electronic device. It is intended to solve various problems for saving information such as microcomputer program execution status and processing results in multiple shut-off to a nonvolatile storage area or a storage area equipped with a backup power source. The present invention can be applied regardless of the type.

  Furthermore, in the above-described embodiment, the case where the system of the present invention is applied to a portable electronic thermometer has been exemplified. However, the present invention is not limited to this, and the system of the present invention can be applied to a portable terminal device (PDA), a cellular phone, a portable game machine, a camera. It can also be applied to portable and portable electronic devices such as portable health devices, audio devices, etc., which are constituted by a microcomputer system using a battery as a power source.

The figure which shows schematic structure of the portable electronic thermometer as an example of the electronic device which has the fuel cell and input-output part to which the microcomputer system which concerns on this invention is applied 1 is a block diagram showing a schematic configuration of the entire system in an embodiment of a microcomputer system according to the present invention. The block diagram which shows schematic structure of the microcomputer part and input / output device in one Embodiment of the microcomputer system which concerns on this invention The block diagram which shows schematic structure of the power supply unit and power supply control part in one Embodiment of the microcomputer system which concerns on this invention The flowchart which shows the schematic main routine of the program in one Embodiment of the microcomputer system which concerns on this invention The flowchart which shows the rough interruption processing program in one Embodiment of the microcomputer system which concerns on this invention Diagram showing the principle of operation of a direct methanol fuel cell (DMFC) The figure which shows the operational relationship between the conventional microcomputer system and a power supply

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Portable electronic thermometer 11: Fuel container 12: Liquid crystal display part 13: Power switch 14: Key input part 15: Reset switch 16: Sensor input part 100: Microcomputer part 101: Power supply unit control input signal 102: Power supply unit control Output signal 110: Processing unit 111: CPU unit 112: Other logic unit 120: Storage unit 121: ROM unit 122: RAM unit 130: Input / output control unit 131: Input / output device control output signal 132: Input / output device control input signal 133: Output control unit 134: Input control unit 200: Power supply unit 201: Power supply control unit 202: Power generation unit 203: Supply control unit 204: Control unit 205: Output circuit 206: Detection unit 207: Determination unit 208: Notification unit 209: Power supply selection part 2 0, 214, 215: Power supply line 211, 212, 213: Fuel path 216: Start-up power supply 217: Power supply internal voltage line 220, 222: Control input signal 221, 223: Control output signal 224: First fuel container state notification signal 225: Power switch signal indicating the state of the power switch and the reset switch 226: Detection means output signal 227: Determination means output signal 250: First fuel container 251: Second fuel container 300: Input / output device

Claims (7)

An input / output device having an interface function with the outside, a processing unit for executing programs and processing data, a storage unit for storing programs and data, and an input / output for transmitting and receiving data and control signals to / from the input / output device A microcomputer system comprising a microcomputer unit including a control unit and a power supply unit for supplying power to the system,
The power supply unit includes a power generation unit including a fuel cell, a power supply control unit having a control function for the microcomputer unit, and a first fuel container that supplies fuel to the power generation unit when main power is supplied into the system. And a second fuel container that supplies fuel to the power generation unit when auxiliary power is supplied into the system,
The first power container and the second fuel container correspond to an activation operation, a steady operation, a standby operation, an end operation, or an emergency operation for an unexpected power interruption executed by the microcomputer unit. A microcomputer system characterized by controlling each fuel supply from. The power supply control unit responds to a detection unit that detects a state of the first fuel container and a state of the microcomputer unit, a determination unit that determines the detected state, and a determination result of the determination unit. Control means for controlling each fuel supply from the first fuel container and the second fuel container, and notification means for outputting a notification signal to the microcomputer unit in response to the determination result,
2. The microcomputer according to claim 1, wherein the microcomputer unit executes an activation operation, a steady operation, a standby operation, an end operation, or an emergency operation for unexpected power cut-off in response to the notification signal. Microcomputer system. The power supply control unit includes detection means for detecting an output voltage of the power supply unit, a state of the first fuel container, and a state of the microcomputer unit, a determination unit for determining the detected state, and the determination Control means for controlling the fuel supply from the first fuel container and the second fuel container in response to the determination result of the means, and notification means for outputting a notification signal to the microcomputer unit in response to the determination result And having
In response to the notification signal, the microcomputer unit does not move the program execution state and execution result information on the storage unit, and starts, steady operation, standby operation, end operation, or unexpected. 2. The microcomputer system according to claim 1, wherein an emergency operation for power-off is executed. The first fuel container is detachably attached to the power supply unit;
4. The microcomputer system according to claim 2, wherein the detection unit has a function of detecting occurrence of an attachment / detachment event of the first fuel container. 5.   3. An application program corresponding to a use executed by the microcomputer unit and a program corresponding to a predetermined operation executed in response to the notification signal are written in the storage unit. 5. The microcomputer system according to any one of 4. The first fuel container is detachably attached to the power supply unit;
The second fuel container is fixed in the power supply unit in a non-detachable manner;
The microcomputer system according to any one of claims 1 to 5, wherein fuel replenishment to the second fuel container is performed by supplying fuel from the first fuel container.   The input / output device has a function of interfacing with the outside by at least one of display, key input, analog input, analog output, digital input, digital output, digital input / output, radio signal input, and radio signal output. The microcomputer system according to claim 1, wherein the microcomputer system has a microcomputer system.

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