JP2016110390A - Parallel communication apparatus and parallel communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable reliable data transmission with a simple configuration.SOLUTION: Each slave device 3-3receives transmission/reception information at prescribed timing. At prescribed timing, the slave device 3-3corresponding to block information in the transmission/reception information reads data from a prescribed address of a transmission memory 5 via a data line if mode information is to read, and writes the already-read data into a prescribed address of a reception memory 6 via the data line if the mode information is to write. In addition, a master device 2 side cuts off the data line at timing when the slave devices 3-3do not access the transmission memory 5 and the reception memory 6.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a parallel communication device and a parallel communication method for transmitting a signal between a master device and a slave device via a bus.

  In general, the serial communication has an advantage over the parallel communication in the number of signals and long-distance transmission, and has an advantage that the number of parts as hardware can be reduced and the configuration can be made inexpensively. On the other hand, since software processing is required, it has a drawback that it cannot be applied to bus communication of control signals not via software processing in devices that require high reliability.

  In addition, as a communication method for exchanging data and addresses between a master device such as a CPU and a slave device such as a storage circuit and an input / output circuit, a parallel method based on the IEEE488 standard, the GPIB standard, or the SCSI standard is used. Communication is known (for example, Patent Document 1).

JP 07-31720 A

  These parallel communication systems are standards that guarantee reliable data transmission / transfer, but have a drawback that, for example, the communication distance in the SCSI standard is 25 m at the maximum, and a standardized expensive cable is required. . In addition, the command system is complex, low versatility and versatility, and is not suitable for devices that do not require high-speed communication or complicated control.

  Accordingly, an object of the present invention is to provide a parallel communication device and a parallel communication method that enable reliable data transmission with a simple configuration.

In order to solve the above-described problem, the invention according to claim 1 is a parallel communication device that transmits a signal between a master device and a plurality of slave devices,
On the master device side, a timing signal is periodically generated and transmitted to each slave device, the address of a transmission memory or reception memory to be accessed, mode information for identifying read or write, and a slave at a transmission / reception destination Block information for identifying a device, and transmission / reception information including the bus signal control means for controlling the data line based on the timing signal,
Each slave device receives the transmission / reception information based on the timing signal, and the slave device corresponding to the block information in the transmission / reception information transmits the transmission when the mode information is read based on the timing signal. Reading data from the address of the memory via the data line, and writing the read data via the data line to the address of the receiving memory when the mode information is a write,
The bus signal control means cuts off the data line between the timing signals when there is no access from the slave devices to the transmission memory and the reception memory.

  According to the present invention, the timing signal is periodically generated and transmitted to each slave device by the bus signal control means on the master device side, and transmission / reception information is set, and each slave device is based on the timing signal. Transmission / reception information is received. Based on the timing signal, the slave device corresponding to the block information in the transmission / reception information reads data from the predetermined address of the transmission memory when the mode information is read, and receives when the mode information is write. The previously read data is written to a predetermined address in the memory.

  According to a second aspect of the present invention, in the parallel communication device according to the first aspect, each slave device performs a parity check on a signal received from the master device side, and when a parity error occurs, the master device side An error signal is transmitted.

The invention according to claim 3 is a parallel communication method for transmitting a signal between a master device and a plurality of slave devices,
On the master device side, a timing signal is periodically generated and transmitted to each slave device, the address of the transmission memory or reception memory to be accessed, mode information for identifying whether it is read or write, and the slave at the transmission / reception destination Set transmission / reception information including block information that identifies the device,
Each slave device receives the transmission / reception information based on the timing signal, and the slave device corresponding to the block information in the transmission / reception information transmits the transmission when the mode information is read based on the timing signal. Reading data from the address of the memory via the data line, and writing the read data via the data line to the address of the reception memory when the mode information is a write,
The master device side is characterized in that the data line is cut off between the timing signals when there is no access from the slave devices to the transmission memory and the reception memory.

  According to a fourth aspect of the present invention, in the parallel communication method according to the third aspect, each of the slave devices performs a parity check on the signal received from the master device side, and when a parity error occurs, the master device side An error signal is transmitted.

  According to the first and third aspects of the present invention, each slave device reads data from the transmission memory and writes the read data to the reception memory. Therefore, whether or not the data is reliably transmitted on the master device side is determined. As a result, it is possible to ensure data transmission. In addition, in the period (between timing signals) where there is no read / write from each slave device to the transmission memory and the reception memory, the data line is cut off, so data collision is avoided and more reliable data transmission is possible.

  Further, it can be configured only by hardware logic that generates a timing signal and sets transmission / reception information on the master device side, and software processing becomes unnecessary. As a result, a simple configuration can be achieved, and reliability can be improved and more reliable data transmission can be achieved.

  According to the second and fourth aspects of the invention, since the parity check is performed on each slave device for the signal received from the master device side, reliable data transmission with higher reliability is possible. In addition, when a parity error occurs, an error signal is transmitted to the master device side, so that appropriate error processing can be performed on the master device side.

It is a schematic block diagram showing a parallel communication device according to an embodiment of the present invention. 2 is a timing chart showing a transmission procedure from a master device to a slave device by the parallel communication device of FIG. 1. 2 is a timing chart showing a reception procedure from a slave device to a master device by the parallel communication device of FIG. 1. 2 is a flowchart showing a data transmission procedure between a master device and each slave device by the parallel communication device of FIG. 1.

  The present invention will be described below based on the illustrated embodiments.

1 to 4 show an embodiment of the present invention, and FIG. 1 is a schematic block diagram showing a parallel communication device 1 according to this embodiment. This parallel communication device 1 is a device for transmitting and transferring signals and data between a master device 2 and a plurality of slave devices 3 _{1 to} 3 _{4. A} bus signal control circuit (bus signal control) is connected to the master device 2 side. Means) 4, a transmission memory 5 and a reception memory 6, and each of the slave devices 3 _{1 to} 3 ₄ includes a memory. Here, in this embodiment, the case where there are four slave devices 3 will be described, but it is needless to say that the number may be other than four.

First, the configuration of each signal will be described. In the 8-bit data configuration, the number of bits per slave device 3 _{1 to} 3 ₄ is 512 bits, and all slave devices 3 _{1 to} 3 ₄ are 2048 bits. The signal (bit) content is as follows.

ADR5 to ADR0: address of data (address of transmission memory 5 or reception memory 6 to be accessed)
MOD2 to MOD0: read / write signal (mode information for identifying whether read or write), the transmission mode or the reception mode is set based on the slave. For example, when only MOD0 is “1”, the read mode (transmission mode), MOD2 Write mode (reception mode) when only 1 is “1”
BLK1~BLK0: (block information identifying the slave devices ₃ 1 to 3 ₄ of the transmission and reception destination) block number of the slave device to transmit and receive data, for example, the communication destination slave device _{3 1} in the case of "00" in binary select selects the slave device 3 ₂ to the communication destination in the case of "01", and the like.
PRTY: Parity signals of ADR5 to ADR0 and MOD2 to MOD0,
The above ADR5 to ADR0, MOD2 to MOD0, BLK1 to BLK0, and PRTY are used as transmission / reception information.
DAT6 to DAT0: Data DATP: Data parity (parity signal of DAT6 to DAT0)
STB1, STB2: Data transmission / reception control (timing signal), 50% duty clock is distributed to two, one clock is delayed and each falling and rising edge (timing signal) is used for bus communication To control.
ERR: Parity checking on PRTY and DATP parity signal, an error signal to be transmitted when a parity error occurs from the slave device ₃ 1 to 3 ₄ to the master device 2

Direction of these signals, the master device 2 as a reference, a signal excluding the DAT6~DAT0 the DATP and ERR is a one-way from the master device 2 to the slave device ₃ 1 to 3 _4. DAT6 to DAT0 and DATP are bidirectional between the master device 2 and the slave devices 3 _{1 to} 3 ₄ and use bidirectional signals. Meanwhile, ERR is the one-way from the slave device ₃ 1 to 3 ₄ to the master device 2 are transmitted via the dedicated line. The signal lines (including data lines) for these signals are differential signals.

Bus signal control circuit 4, STB 1, STB 2 sends (timing signal) was periodically generated in each slave device ₃ 1 _{~3 4, ADR5~ADR0} the MOD2~MOD0 the BLK1~BLK0 and PRTY (reception information ) To control the data line based on STB1 and STB2.

Each slave device 3 _{1 to} 3 ₄ receives transmission / reception information based on STB1 and STB2, and slave devices 3 _{1 to} 3 ₄ corresponding to BLK1 to BLK0 (block information) in the transmission / reception information are STB1, Based on STB2, when MOD2 to MOD0 (mode information) is read, data is read from the ADR5 to ADR0 (predetermined address) of the transmission memory 5 via the data line, and when MOD2 to MOD0 is write, the reception memory 6 The previously read data is written to ADR5 to ADR0 via the data line. The bus signal control circuit 4, there is no access from the respective slave devices ₃ 1 to 3 ₄ to the transmission memory 5 and the receiving memory 6, to block the data line between STB 1, between STB 2 (timing signal). On the other hand, each of the slave devices 3 _{1 to} 3 ₄ performs a parity check on the signal received from the master device 2 side, that is, a parity check is performed on the parity signals of PRTY and DATP, and when a parity error occurs, the master device 2 ERR (error signal) is transmitted.

  Next, the operation of the parallel communication device 1 and the parallel communication method by the parallel communication device 1 will be specifically described with reference to FIGS.

As shown in FIGS. 2 and 3, the master device 2 periodically generates STB 1 and STB 2 and transmits them to the slave devices 3 _{1 to} 3 ₄ . In this state, when the master device 2 for transmission to the respective slave devices ₃ 1 to 3 _4, first, in the master device 2 at a predetermined timing, sets the ADR5~ADR0 and MOD2~MOD0 the BLK1~BLK0 and PRTY ( Step S1). Here, MOD2 to MOD0 are set to the read mode. Next, at the falling timing of STB1, the master device 2 sets the data lines DAT6 to DAT0 and DATP in the transmission direction (step S2). At the same time, the slave devices 3 _{1 to} 3 ₄ determine and receive ADR5 to ADR0, MOD2 to MOD0, BLK1 to BLK0, and PRTY (step S3).

Subsequently, at the falling timing of STB2, slave devices 3 _{1 to} 3 ₄ corresponding to BLK1 to BLK0 determine and receive DAT6 to DAT0 and DATP (step S4). Further, at the rising timing of STB1, the slave devices 3 _{1 to} 3 ₄ read data from ADR5 to ADR0 of the transmission memory 5 via the data line, and write and store them in their own memory (step S5). At the same time, in the slave devices 3 _{1 to} 3 ₄ , parity check is performed on the parity signals of PRTY and DATP, and when a parity error occurs, an ERR (error signal) is transmitted to the master device 2.

The rising timing of the STB 2, that is, at the timing is not read from the slave device ₃ 1 to 3 ₄ to the transmission memory 5 is for blocking and release the data line (step S6).

On the other hand, in the case of transmission from each slave device 3 _{1 to} 3 ₄ to the master device 2 (when the master device 2 receives from each slave device 3 _{1 to} 3 ₄ ), first, as shown in FIG. In step S11, ADR5 to ADR0, MOD2 to MOD0, BLK1 to BLK0, and PRTY are set (step S11). Here, MOD2 to MOD0 are set to the write mode. Next, at the falling timing of STB1, the master device 2 sets the data lines DAT6 to DAT0 and DATP in the receiving direction (step S12). At the same time, the slave devices 3 _{1 to} 3 ₄ determine and receive ADR5 to ADR0, MOD2 to MOD0, BLK1 to BLK0, and PRTY (step S13).

Subsequently, at the falling timing of STB2, slave devices 3 _{1 to} 3 ₄ corresponding to BLK1 to BLK0 receive the data (data read in step S5) stored in its own memory via the data line. Write to ADR5 to ADR0 of the memory 6 (step S14). Further, in the slave devices 3 _{1 to} 3 ₄ , parity check is performed on the parity signal of PRTY, and when a parity error occurs, an ERR (error signal) is transmitted to the master device 2 (step S14).

At the same time, the master device 2 determines the received DAT6 to DAT0 and DATP at the falling timing of STB2 (step S15). Subsequently, the rise timing of the STB 2, that is, at the timing does not have write from each slave device ₃ 1 to 3 ₄ to the received memory 6 is for blocking and release the data line (step S16).

Such reading and writing are sequentially performed between the master device 2 and each of the slave devices 3 _{1 to} 3 ₄ . That is, as shown in FIG. 4, first, by the first slave device 3 _1, performs the writing of data to and reading data from the transmission memory 5 to the receive memory 6 (step S21). Similarly, the second slave device 3 ₂ , the third slave device 3 _3, and the fourth slave device 3 ₄ sequentially read data from the transmission memory 5 and write data to the reception memory 6. Perform (Steps S22 to S24). Subsequently, returning to step S21, similar transmission / reception is repeated.

As described above, according to the parallel communication apparatus 1 and parallel communication methods, with each slave device 3 ₁ to 3 _4, reads data from the transmission memory 5, for writing the read data to the receiving memory 6, the master device It is possible to confirm whether data is reliably transmitted on the second side, and as a result, reliable data transmission is possible. Moreover, in a period no write from each slave device 3 ₁ to 3 ₄ to the transmission memory 5 and the receiving memory 6 (between the rising timing of STB2 to the fall timing of the STB 1), the data line is blocked and opening Therefore, data collision is avoided and more reliable data transmission is possible.

Further, control of the bus communication is carried out every master device 2 side (the bus signal control circuit 4) is not performed by each slave device 3 ₁ to 3 _4. Moreover, STB1 and STB2 can be generated on the master device 2 side, and transmission / reception information such as ADR5 to ADR0 and MOD2 to MOD0 can be configured only by hardware logic, which eliminates the need for software processing. It becomes possible. In addition, command control is not required because software is not used with a simple logic configuration. As a result, a simple and inexpensive configuration can be achieved, and reliability can be improved and more reliable data transmission can be achieved. On the other hand, since the signal line is a differential signal, it is resistant to noise and enables long distance communication compared to parallel communication.

The signal received from the master device 2, i.e., ADR5～ADR0 and the MOD2~MOD0 and DAT6～DAT0, for parity check on each slave devices ₃ 1 to 3 _4, allows higher reliable data transmission reliability It becomes. In addition, when a parity error occurs, an ERR is transmitted to the master device 2, so that appropriate error processing can be performed in the master device 2.

  In this way, reliable data transmission is possible with a simple and inexpensive configuration, so it is not enough to control with standardized serial communication or parallel communication, but there are few wires for input / output signals such as discrete signals and sensor signals.・ Equipment (such as camera control and remote operation of a temperature sensor) that is desired to communicate via a communication line can be realized at low cost. In addition, it has an ERR that can stop the bus communication in hardware so that it can be applied to equipment that wants to perform reliable control and monitoring for multiple equipment. It can be used for dangerous equipment.

Although the embodiment of the present invention has been described above, the specific configuration is not limited to the above embodiment, and even if there is a design change or the like without departing from the gist of the present invention, Included in the invention. For example, in the above embodiment, after reading data from the transmission memory 5 and writing data to the reception memory 6 by one slave device 3 _{1 to} 3 ₄ , the next slave device 3 ₁ to 3 3 is performed ₄ to the processing by the data of after the reading of data from the transmission memory 5 by all of the slave devices 3 ₁ to 3 _4, the receive memory 6 by all the slave devices 3 ₁ to 3 ₄ May be written.

1 Parallel communication device 2 Master device 3 _{1 to} 3 ₄ Slave device 4 Bus signal control circuit (bus signal control means)
5 Transmission memory 6 Reception memory

Claims (4)

A parallel communication device that transmits signals between a master device and a plurality of slave devices,
On the master device side, a timing signal is periodically generated and transmitted to each slave device, the address of a transmission memory or reception memory to be accessed, mode information for identifying read or write, and a slave at a transmission / reception destination Block information for identifying a device, and transmission / reception information including the bus signal control means for controlling the data line based on the timing signal,
Each slave device receives the transmission / reception information based on the timing signal, and the slave device corresponding to the block information in the transmission / reception information transmits the transmission when the mode information is read based on the timing signal. Reading data from the address of the memory via the data line, and writing the read data via the data line to the address of the receiving memory when the mode information is a write,
The bus signal control means shuts off the data line between the timing signals without access from the slave devices to the transmission memory and the reception memory.
A parallel communication device characterized by that. Each slave device performs a parity check on the signal received from the master device side, and when a parity error occurs, transmits an error signal to the master device side.
The parallel communication device according to claim 1. A parallel communication method for transmitting a signal between a master device and a plurality of slave devices,
On the master device side, a timing signal is periodically generated and transmitted to each slave device, the address of the transmission memory or reception memory to be accessed, mode information for identifying whether it is read or write, and the slave at the transmission / reception destination Set transmission / reception information including block information that identifies the device,
Each slave device receives the transmission / reception information based on the timing signal, and the slave device corresponding to the block information in the transmission / reception information transmits the transmission when the mode information is read based on the timing signal. Reading data from the address of the memory via the data line, and writing the read data via the data line to the address of the reception memory when the mode information is a write,
On the master device side, there is no access from the slave devices to the transmission memory and the reception memory, and the data line is cut off between the timing signals.
A parallel communication method characterized by the above. Each slave device performs a parity check on the signal received from the master device side, and when a parity error occurs, transmits an error signal to the master device side.
The parallel communication method according to claim 3.

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