JP2522613B2 - Multiplexer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex transmission device using a time division system, and is used, for example, in a system for controlling a lighting load, an air conditioning load, an electric lock, etc. by the multiplex transmission. is there.

[0002]

2. Description of the Related Art FIG. 2 is a schematic block diagram of a conventional general time division multiplex transmission apparatus. In this device, one parent device A and a plurality of terminal devices B1, B2, ... Are connected via a two-wire transmission line L such as a coaxial cable or a twisted pair wire. 4A and 4B, the time-division multiplex transmission signal sent from the base unit A to the transmission line L and the terminal units B1, B2, ... Reply to the base unit A via the transmission line L. The waveforms of the reply signals are shown. The time division multiplex transmission signal is 1
In the frame FR, a start pulse ST indicating the start of signal transmission, an address pulse AD for designating a terminal device Bi (i = 1, 2, ...) To communicate with, and an operation for controlling the operation of the terminal device Bi. It includes at least a control pulse DT and a reply waiting time zone RT for receiving a reply signal (monitoring pulse) from the terminal device Bi. The address pulse AD and the control pulse DT are composed of, for example, a serial signal of a plurality of bits meaning that the long voltage pulse is 1 and the short voltage pulse is 0. In the reply waiting time zone RT, for example, by applying a voltage between the transmission lines L on the side of the base unit A and shorting the lines of the transmission lines L on the side of the terminal device Bi via a resistor, for example, ,
A multi-bit serial signal, which means that the long current pulse is 1 and the short current pulse is 0, is returned to the master unit A. The address pulse AD and the control pulse DT are sent from the base unit A as low impedance voltage signals, and in each terminal device Bi, a rectifier and a smoothing capacitor are connected between the transmission lines L to obtain an operating power supply. The address pulse AD included in the time division multiplex transmission signal transmitted from the base unit A is changed so as to poll each terminal device Bi, for example, cyclically, and only one terminal device Bi having the matched address is controlled. The control operation and the reply operation according to the pulse are performed. When the start pulse ST is received from the transmission line L, the terminal device Bi receives the subsequent address pulse AD and collates with its own address. If the addresses match, the control pulse DT following the address pulse AD is received, and the control operation is performed according to the control pulse DT. Further, a reply signal as shown in FIG. 4B is sent in the reply waiting time zone RT following the control pulse DT.

FIG. 3 shows the internal structure of the terminal Bi. The multiplex transmission signal processing unit 1 has a function of receiving a multiplex transmission signal transmitted from the master unit A and returning a reply signal, and is usually configured by using a microcomputer. The terminal device Bi can communicate with the setting device C. The setting device C is used to set the function of the terminal device Bi. The functions of the terminal device Bi include, for example, a type of terminal device for monitoring for operating a wall switch and an operation of a sensor, a terminal device for controlling a load such as a lighting load and an air conditioning load, and the like. , And the address of the terminal device Bi is also included. When the terminal device Bi is a terminal device for monitoring, the input / output processing unit 3 inputs the states of the wall switch and the sensor, and inputs them to the multiplex transmission signal processing unit 1 as monitoring information. Further, when the terminal device Bi is a terminal device for load control, the input / output processing unit 3 outputs the control information from the multiplex transmission signal processing unit 1 to a lighting load, an air conditioning load, or the like. Since the power supply of the terminal device Bi is supplied from the multiplex transmission line L as described above, when the multiplex transmission signal from the parent device A is stopped due to a power failure or the like, the power supply of the terminal device Bi is cut off. Even in such a case, the non-volatile memory F is built in the terminal device Bi so that the information of the terminal device Bi is not lost. The non-volatile memory F is, for example, EEPRO.
It has the advantage that the stored contents are not erased even when the power is cut off, but it has a drawback that the access speed is slow. Therefore, when the power of the terminal device Bi is turned on, the non-volatile memory F changes to the volatile memory K.
It has been proposed that the multiplex transmission signal processing unit 1 access the volatile memory K by reading the information. The volatile memory K is composed of, for example, a RAM and has a drawback that the stored contents are erased when the power is cut off, but instead has an advantage that the access speed is fast. As described above, by using the two types of memories together, it is possible to achieve both retention of stored contents when power is cut off and high-speed access speed. In the setting device C, not only the function is written in the non-volatile memory F, but also the function written in the non-volatile memory F can be read and displayed for confirmation. This setting device C
The setting signal transmission / reception processing unit 2 writes / reads the nonvolatile memory F by.

[0004]

In the above conventional technique, the data written in the non-volatile memory F has many modes depending on the type and function of the terminal, and the operation of the terminal in each mode. In order to perform the test, it is necessary to rewrite the data in the non-volatile memory F each time, and there is a problem that the operation test of the terminal device takes a very long time. For example, the number of modes to be tested is 10
0 types, time to write data to non-volatile memory F is 2
Even if it is 5 msec, it is 100 × 25 msec.
It takes a long time of 2.5 sec. Moreover, since the setter C sends and receives the setting signal serially, it takes 500 msec just to send the setting signal for writing the data to the non-volatile memory F, and the clock for this serial communication is about 10 times. Since it is 50 msec at the fastest, overall, for example, 50 msec × 100 =
It also requires 5 seconds. This results in a very long test time, which increases the cost of the terminal.

The present invention has been made in view of the above points, and an object of the present invention is to store the function of a terminal device in a non-volatile memory and transfer it to a volatile memory to read it. In the multiplex transmission device, the data rewriting time of the non-volatile memory, which occupies a large part of the test time of the terminal device, is shortened and the cost increase of the terminal device is prevented.

[0006]

In order to solve the above problems, the present invention provides a common transmission line for a plurality of terminals B1, B2, ... Assigned unique addresses as shown in FIG. It is connected to the base unit A via L, the control pulse is transmitted to each of the terminals B1, B2, ... In response to the address designation from the base unit A, and the monitoring pulse is returned from the addressed terminal unit to the base unit A. In the multiplex transmission device configured as described above, each terminal device Bi includes a multiplex transmission signal processing unit 1 that executes a multiplex transmission process with the master device A and a terminal device B as shown in FIG.
A setting signal transmission / reception processing unit 2 for transmitting / receiving a setting signal to / from a setting device C for setting the function of i, a non-volatile memory F for holding the function of the terminal device Bi when the power is cut off, and a non-interruption of power supply The volatile memory K, which is transferred from the multiplex transmission signal processing unit 1 when the function of the terminal device Bi stored in the nonvolatile memory F is sometimes read, and the nonvolatile memory F is used in the test mode for testing the operation of the terminal device Bi. Instead, it has a writing circuit section 5 for directly writing the function of the terminal device Bi in the volatile memory K. Ma
In addition, the test mode is indicated to the terminal device Bi as a monitoring signal.
When a signal is input, this signal is decoded and the test mode
Providing a test mode decoding unit 4 for judging that the user has entered
Is preferred. The write circuit section 5 is input during the test mode.
Rewriting the volatile memory K using the monitoring signal
Is preferred.

[0007]

According to the present invention, the nonvolatile memory F is thus used in the test mode for testing the operation of the terminal Bi.
Since the write circuit unit 5 for directly writing the function of the terminal device Bi is provided in the volatile memory K without the intervention of the device, even if there are many functions to be tested for operation, the function of the terminal device Bi can be quickly processed. Can be rewritten to test whether or not the terminal device Bi operates normally for each function, and the time required for the test can be shortened. Also the supervisory signal
To determine that the test mode has been entered,
By rewriting the volatile memory K, the terminal device Bi
Test without providing a terminal for test mode
Enter the mode or rewrite the volatile memory K.
It becomes possible.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a terminal device Bi used in the multiplex transmission apparatus of the present invention.
This configuration is shown as an example. Multiplex transmission signal processing unit 1
Has a function of receiving a multiplex transmission signal transmitted from the parent device A to receive control information and returning a monitoring pulse. The setting signal transmission / reception processing unit 2 has a function of performing communication processing with the setting device C. Next, the nonvolatile memory F is
For example, it is composed of an EEPROM, and the stored contents are not erased even when the power is cut off. The nonvolatile memory F is accessed by the setting signal transmission / reception processing unit 2 and stores the function table of the terminal device Bi. The volatile memory K is, for example, a RAM, and the stored contents are lost when the power is cut off, but the volatile memory K has a faster access speed than the nonvolatile memory F. The function table of the non-volatile memory F is transferred to the volatile memory K, and the function table is accessed by the multiplex transmission signal processing unit 1 to determine the operation of the terminal device Bi. The input / output processing unit 3 inputs a monitoring signal to the terminal device Bi and outputs a control signal from the terminal device Bi. In the present embodiment, by using the monitoring signal input to the input / output processing unit 3, it is possible to enter the test mode without providing a terminal for the test mode. That is, the monitoring signal input to the input / output processing unit 3 is input to the test mode decoding unit 4, and when a signal indicating the test mode is input as the monitoring signal, the test mode decoding unit 4
Then, this signal is decoded and it is judged that the test mode has been entered. In the test mode, the monitoring signal input to the input / output processing unit 3 is transmitted via the writing circuit unit 5 to the volatile memory K.
Will be written directly to.

In this embodiment, since the data writing time to the function table of the volatile memory K is merely data writing to the RAM, the clock speed is increased to several μ.
It can be shortened to sec to several tens of μsec, and even if there are about 100 or more types of data (mode) to be written in the function table, the time required for the writing is several hundred μs.
It is very short, from c to several msec, and it is possible to prevent the cost increase of the terminal device due to the test. Further, by providing the test mode decoding unit 4, there is no need to increase the number of external terminals,
Even when the terminal device Bi is integrated into a circuit, the number of pins does not increase, so that the cost does not increase. Further, when the test mode decoding unit 4 decodes the test mode, the clock can be speeded up to speed up the tests of the multiplex transmission signal processing unit 1, the setting signal transmission / reception processing unit 2, and the like. .

In the above description, as shown in FIG. 2, an example is shown in which two terminals B1 and B2 are connected to the transmission line L, but the number of terminals is limited to this. For example, if an 8-bit address is assigned, a maximum of 256 units can be connected.

[0011]

According to the present invention, in the multiplex transmission device in which the function of the terminal is stored in the non-volatile memory and is transferred to the volatile memory and read out, a large part of the test time of the terminal is occupied. Since the time for rewriting data in the non-volatile memory is eliminated, the time required for the test can be significantly shortened, and this has the effect of preventing an increase in the cost of the terminal device. In addition, the monitoring signal
Use to judge that the test mode has been entered or volatilize
Test the terminal by rewriting the memory
No need for additional mode terminals, especially integrated circuits
If you want to increase the cost of the terminal
Without increasing the test mode speed.
Wear.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a conventional multiplex transmission device.

FIG. 3 is a block diagram showing an internal configuration of a terminal used in a conventional example.

FIG. 4 is a waveform diagram showing a multiplex transmission signal and a reply signal.

[Explanation of Codes] 1 multiplex transmission signal processing unit 2 setting signal transmission / reception processing unit 3 input / output processing unit 4 test mode decoding unit 5 writing circuit unit A master unit B1 terminal device B2 terminal device Bi terminal device C setting device L transmission Line F Non-volatile memory K Volatile memory

Claims (3)

(57) [Claims] 1. A plurality of terminals to which unique addresses are assigned are connected to a master unit via a common transmission line, and control pulses are transmitted to each terminal unit by address designation from the master unit and are addressed. In the multiplex transmission device in which a monitoring pulse is returned from the terminal device to the master device, each terminal device sets the multiplex transmission signal processing unit that executes the multiplex transmission process with the master device and the function of the terminal device. Setting signal transmission / reception processing unit that transmits / receives a setting signal to / from a setting device for storing, a non-volatile memory for retaining the function of the terminal device when the power is cut off, and a terminal stored in the non-volatile memory when the power supply is not cut off. The function of the terminal is transferred and read from the multiplex transmission signal processing unit, and the function of the terminal is directly written to the volatile memory without the non-volatile memory in the test mode for testing the operation of the terminal. A multiplex transmission device having a writing circuit unit for inserting the same. 2. A test mode as a supervisory signal for the terminal device.
When a signal indicating is input, it is decoded and tested.
A test mode decoding unit was installed to judge that
The multiplex transmission device according to claim 1, wherein 3. The writing circuit section is a terminal in the test mode.
Rewrite the volatile memory using the monitoring signal input to the device
Multiplex transmission according to claim 1 or 2, characterized in that
apparatus.