JPH05336082A - Detection of response data validity - Google Patents

Abstract

PURPOSE:To shorten the time of the overall command processing by eliminating the wait time due to transmission of response data corresponding to command data from a station B to a station A in the reception order of command data in the case of the station B capable of multiple execution of processings for command data continuously received from the station A. CONSTITUTION:A station A 01 adds a sequential code 3 indicating the order of transmission to command data 1 to transmit it to a station B 02. The station B 02 adds the same sequential code 3 as command data to response data 2 as the processing result to transmit it to the station A 01 immediately after processing the command.

Description

Detailed Description of the Invention

[0001]

The present invention relates to data transmission between two stations,
The present invention relates to a method of transmitting command data from a local station to a partner station and detecting the validity of response data received from the partner station.
In the following figures, the same reference numerals indicate the same or corresponding parts.

[0002]

2. Description of the Related Art FIG. 2 shows a command (processing request) data 1 transmitted from the A station 01 to the B station 02 in the data transmission between the A station 01 and the B station 02. It indicates that the response data 2 as the processing result is transmitted to the A station 01. The transmission procedure uses the simplest and cheapest non-procedure. This method allows transmission of an arbitrary bit pattern without a special transmission control code, but the reliability of transmission is significantly reduced. In this transmission, the correctness of the response data to the command data is checked by detecting the transmission error check status (parity, overrun, etc.) attached to the message during transmission and reception.

[0003]

However, in the above-described conventional method for detecting the validity of response data, the following problems occur when the B station 02 can receive multiple commands. That is, when the station B 02 receives the continuous commands 1, the processing corresponding to each command 1 is executed in parallel. At this time, the processing time of each command 1 cannot be kept constant due to the load of the station B or the like. Further, depending on the priority level set for the command processing, the processing of the command received later may be completed before the previous command. However, in the normal simple transmission protocol, the B station 02 cannot return the response data 2 for the subsequent command 1 until it returns the response data 2 for the first command 1 to the A station 01. Therefore, command 1 issued by station A 01 continuously
However, there is a drawback that the total processing time becomes longer.

Therefore, an object of the present invention is to introduce a more complicated transmission protocol to the legitimacy of the response data 2 even if the reception order of the response data 2 for the continuous command 1 is reversed at the A station 01 side. It is to provide a method of detecting the validity of response data that can be easily checked without performing the above.

[0005]

In order to solve the above-mentioned problems, in the method of detecting the validity of responsiveness data according to the present invention, the second station (station B 02 etc.) is the first station (station A). In a system for transmitting response data (2, etc.) as the execution result of each process to the first station while executing multiple processes for command data (1, etc.) continuously received from 01, etc.) In the method for detecting the legitimacy of the response data received by the first station, the first station adds a sequential code (3 or the like) indicating the order of transmission to the command data, and transmits the command data. Station transmits the response data corresponding to the received command data by adding the same sequential code as the sequential code added to the command data.

[0006]

The station A adds a sequential code indicating the order of transmission to the command data and sends it to the station B, and the station B adds the sequential code added to the command data to the response data corresponding to the received command data. The same sequential code as is added and transmitted to station A.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory diagram of a communication method between two stations as an embodiment of the present invention and corresponds to FIG. In FIG. 1, the A station 01 continuously transmits commands to the B station 02, and the B station 02 can perform multiple processes for the received commands. In this case, according to the present invention, the sequential code 3 is added to each of the transmitted and received command data 1 and response data 2. The sequential code 3 of 2 is set in the 1-byte area by the A station 01 which is the transmission side of the command data 1. Further, the value of the sequential code 3 is incremented by 1 every time new command data 1 is transmitted and becomes a value of 00 to FFH. However, 00H follows FFH.

Station B 02, which has received the command data 1,
Sequential code 3 added to command data 1
Is copied to the response data 2 corresponding to the command data and transmitted to the A station 01. The station A 01 which receives the response data 2 can detect the validity of the response data 2 with respect to the command data 1 by comparing the sequential code 3 of the transmitted command data 1 with the sequential code 3 of the received response data 2. It will be possible.

[0009]

According to the present invention, station A adds a sequential code indicating the order of transmission to the command data continuously transmitted to station B, and station B multiplexes the processing corresponding to the received command data. And the response data as the execution result is added with the same sequential code as the sequential code added to the command data.
Since it is transmitted to the station, the station A side, that is, the station on the command transmission side, responds to the command data 1 with the response data 2
Since it is possible to easily check the correctness of the command and the command 1 can be processed in parallel, the total processing time of all commands can be shortened.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a communication method as an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a conventional communication method corresponding to FIG.

[Explanation of symbols]

 01 Station A 02 Station B 1 Command data 2 Response data 3 Sequential code

Claims (1)

[Claims] 1. The second station multiplexes each process for command data continuously received from the first station,
In the method of detecting the validity of the response data received by the first station in the system for transmitting the response data as the execution result of each process to the first station, the first station converts the command data into the command data. The second station adds and transmits a sequential code indicating the order of transmission, and the second station adds and transmits the same sequential code as the sequential code added to the command data to the response data corresponding to the received command data. A method for detecting the validity of response data, which is characterized in that