Block Number; Frame Id No; Sum Check Code - Mitsubishi Electric MELSEC IQ-R series Reference Manual

Block number

Block number is an arbitrary number defined by an external device and used for data defragmentation.
Block number converts data to 2-digit (hexadecimal) ASCII code within the range of '00H' to 'FFH' and sent them from the
upper digits.
C24 only checks if the block number is specified within the correct range. It does not check whether the block numbers are
sent in order.

Frame ID No.

Specify the frame to be used.
Type
4C frame
3C frame
2C frame
1C frame
Setting method
■Data communication in ASCII code
Convert the numerical value to 2-digit ASCII code (hexadecimal), and send it from the upper digits.
■Data communication in binary code
Send a 1-byte numerical value.
Ex.
For 4C frame (F8)
ASCII code
F 8
46 38
H H

Sum check code

Set the sum check code when performing sum check.
For sum check code, set the value to be calculated from the data with the range of sum check for error detection.
Sum check
Sum check is a function for detecting error when data changes while data transmission.
Set the sum check existence by Engineering tool.
■When sum check code is set to "Exist"
Attach a sum check code to the request message.
C24 checks the sum check code. The sum check code is added to the response message.
■When sum check code is set to "None"
The sum check code is not required for the request message.
C24 does not check the sum check code. The sum check code is not added to the response message.
4 MESSAGES OF SERIAL COMMUNICATION MODULE
36
4.3 Details of Setting Data
Setting value
F8
F9
FB
 (Not required)
Binary code
F8
H