JPH02193429A - Method for communication between devices - Google Patents

Abstract

PURPOSE:To detect the occurrence of communication trouble by a simple circuit by setting a pattern for communication trouble detection to specific bits of a transfer block for data transfer by a transmission-side device and monitoring whether the communication trouble occurs or not from the bit positions by a reception-side device. CONSTITUTION:For the communication between the devices which transfer data by serial transmission, the transmitter 11 sets the pattern for communication trouble detection to the specific bits 14 of the transfer block 13 and transmits the data. The receiver 12 detect whether or not there is the pattern for communication trouble detection set on the transmission side at the same bit positions 14 at the time of reception. When there is the pattern, it is decided that the data transfer is performed normally and when not, it is decided that some trouble has occurred.

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to an inter-device communication method for transferring data between two or more devices by serial transmission.

The purpose is to make it possible to detect communication failures with a simple circuit while transferring data through serial transmission, thereby increasing the reliability of signal transmission between devices and guaranteeing reliable device operation.

The transmitting device sets a communication failure detection pattern in a predetermined plurality of bits of a transfer block for data transfer, and the receiving device detects a communication failure detection pattern from the above-mentioned plurality of bit positions in the received transfer block. The system is configured to monitor whether or not a communication failure has occurred.

[Industrial application field]

The present invention relates to an inter-device communication method for transferring data between two or more devices by serial transmission.

For signal transmission and reception between devices, it is necessary to use serial transmission, which requires fewer signal lines, and to be able to guarantee reliable signal transmission with a simple circuit configuration.

[Conventional technology]

In the case of a system in which machine modifications can be made using a free slot system, etc., there are limits to the functions that can be implemented per device (for example, card, puff cage, printed circuit board, etc.). For this reason, there may be cases where all functions cannot be implemented in one device due to new development or the like. In such a case, 2
One function will be implemented across the above devices.

As a result, it becomes necessary to transmit and receive a considerable number of various signals between devices.

As a signal transmission method between such devices.

A large number of wires (for example, 20, 30 wires) between the devices correspond to each signal.
There are two types of transmission methods: a parallel transmission method that uses signal lines, and a serial transmission method that uses a single signal line to sequentially transmit various signals in time series.

Generally, serial transmission is used instead of parallel transmission because it is necessary to reduce the number of signal lines between devices.

[Problem to be solved by the invention]

In order to perform highly reliable serial communication without transfer errors, it is considered optimal to install a processor or the like in each device and connect two communication protocols for communication. However, in this case, the scale of the nine circuits becomes large.

Therefore, a method may be considered in which signals are transferred simply by serial synchronous communication, but in that case, device operation cannot be guaranteed against communication failures due to common lock disturbances, etc.

That is, the simplest serial communication between devices.

As shown in FIG. 4, a common lock A is used between the devices to transmit a leading signal B indicating the beginning of one communication data and serial data C' between the devices, and on the receiving side, data C' is transmitted by the leading signal B. The content of data C' is read at the timing of clock A by determining the leading position of data C'.

However, in this method, 3 For example, clock A
For example, on the transmitting side, (Do, DIT D
21 Da, Da, Ds-) = (0°1.1,1.
0.1-), but if the clock corresponding to data D3 on the receiving side disappears, on the receiving side, (Do, DI, D2゜Da r Da + D
5'--・) = (0, 1, 1, 0, 1゜0~) is judged to have been received, as a result,
D3=0. This may result in an operation based on incorrect logic such as D4=1, which may result in inconsistent states between devices or malfunction of the devices.

Therefore, an object of the present invention is to make it possible to detect the occurrence of a communication failure with a simple circuit while transferring data through serial transmission, thereby increasing the reliability of signal transmission between devices and ensuring reliable device operation. There is a particular thing.

[Means to solve the problem]

FIG. 1 is a diagram for explaining the principle according to the present invention.

The inter-device communication method according to the present invention is an inter-device communication method in which data is transferred between devices by serial transmission, and in the sending device 11, a communication failure occurs in a predetermined plurality of bits 14 of a transfer block 13 for data transfer. A detection pattern is set, and the receiving device 12 is configured to monitor whether or not a communication failure has occurred by detecting the communication failure detection pattern from the plurality of bit positions 14 of the received transfer block 13. Ru.

[Effect]

When transmitting, a communication failure detection pattern is set in a predetermined bin 14 of the transfer block 13, and when receiving, a check is made to see if there is a communication failure detection pattern set at the same bit position 14 on the transmitting side. To detect. If there is a pattern, it is determined that the data transfer was successful;
If there is no pattern, it is determined that some kind of communication failure has occurred.

[Example] The present invention will be described in detail below with reference to two drawings. FIG. 2 is a block diagram showing the configuration of a receiving side device that performs an inter-device communication method as an embodiment of the present invention.

In FIG. 2, 1 to 3 are clocks A, respectively.

This is a buffer for data C and data start signal B.

Data C is stored in m shift registers 41 to 41 connected in series.
4m are input sequentially. In addition, each shift register 41~
A clock A that determines shift timing is input to 41.

The MSBs (most significant bits) of these shift registers 41 to 4 are respectively input to the fixed pattern comparison circuit 5, and data outputs other than the MSB are input to data latches 6 and 6, respectively.

Fixed pattern comparison circuit 5 and data latches 61 to 6m
Data start signal B is input to .

At the input timing of the data head signal B, the fixed pattern comparison circuit 5 compares the input cover pattern created by each MSB with the fixed pattern stored therein, and the data latches 61 to 6- latch the input data.

The data outputs of the data latches 6, ~6- are input to data launches 71~7■, respectively, and these data launches 71~7- respond to the input data in response to the received data valid signal from the fixed pattern comparison circuit 5. Perform the latch.

The operation of the embodiment device will be explained below. First, on the sending side,
Transfer data D as shown in FIG.

~Dn block is divided into m small blocks 81~B- as shown in FIG. 3, and each small block 81~Bm
A predetermined fixed pattern for detecting a communication failure is set in the first M (MSB) bit. Therefore, this fixed pattern is m
It becomes a pattern of bits. These small blocks 81 to B- are sequentially serially transmitted to the receiving side.

On the receiving side, the serially transmitted data is sequentially input into shift registers 41 to 4 to convert the received serial data into parallel data.

By this operation, when the data start signal B is input, the shift registers 41 to 4- are filled with the small blocks B1 to B of the previous cycle.
m will be retained.

Therefore, when the data start signal B is input, the small blocks B, -B- of the previous cycle held in each shift register 41-4- are transferred to data latches 6°-6■, and at the same time, the fixed pattern comparison circuit 5 Shift registers 41-4
An input pattern for communication failure detection formed by the MSB of I+ (therefore, a communication failure detection pattern formed by the first bit of each small block B, ~B intestine) and a predetermined fixed pattern (for communication failure detection) Compare the pattern with the same pattern) If both patterns match, clock A
In this case, the fixed pattern comparison circuit 5 sends the received data valid signal E to each of the data latches 71 to 7■.

As a result, the data launches 71 to 7- are connected to the data latch 61.
The latch contents of ~6- are taken in and outputted in parallel inside the receiving device as normal reception data.

Further, if the pattern comparison in the fixed pattern comparison circuit 5 does not match, it is determined that there is a communication failure in the received data, and the received data is discarded.

Various modifications are possible in implementing the present invention. For example, in the above embodiment, the communication failure detection pattern was constructed from the leading bit of each small block obtained by subdividing the transfer block, but of course this is not limited to this. For example, the bits may be composed of bits at other positions within each small block.

〔Effect of the invention〕

According to the present invention, when performing data transfer by serial transmission, it is possible to detect the occurrence of a communication failure with a simple circuit, thereby increasing the reliability of signal transmission between devices and ensuring reliable device operation. can be guaranteed.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the principle of the present invention. FIG. 2 is a block diagram showing a receiving side device that performs an inter-device communication method as an embodiment of the present invention. FIG. 3 is a diagram for explaining data transmission by the embodiment device; FIG. 4 is a diagram for explaining serial communication. In fig. 1-3-・Buffer 4, ~4I-・-Shift register 5-・Fixed pattern comparison circuit 6, ~6-・-・Data launch 71-7■・-・Data latch payment return

Claims (1)

[Claims] An inter-device communication method for transferring data between devices by serial transmission, wherein the sending device (11) transmits data to a predetermined plurality of bits (14) of a transfer block (13) for data transfer. A communication failure detection pattern is set, and the receiving device (12) transfers the received transfer block (1
3) An inter-device communication method configured to monitor whether or not a communication failure occurs by detecting the communication failure detection pattern from the plurality of bit positions (14).