Mitsubishi Electric MELSEC iQ-RJ71C24-R4 - Page 259

13 CONTENTS AND REGISTRATION OF USER FRAMES FOR DATA COMMUNICATION
13.1 User Frame Types and Contents During Communication
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■C24 processing to registered code FFH+E5H
The sum check code that calculates data (message) to be transmitted/received excluding the first one frame and last one
frame is expressed as the ASCII code data and transmitted or received.
• How to calculate the sum check code
Lower one byte of the calculated sum check code is converted into 2-digit ASCII code data, and transmitted and received.
Ex.
Arrangement of data when transmitted/received
■C24 processing to registered code FFH+EBH
The sum check code that calculates the data (message) to be transmitted/received, including the first one frame and
excluding the last one frame, is expressed as the ASCII code data, and transmitted or received.
• How to calculate the sum check code
Lower one byte of the calculated sum check code is converted into 2-digit ASCII code data, and transmitted or received.
Ex.
Arrangement of data when transmitted/received
011770 30
02H 30H
02H
03H
03H FFH+E5H
31H 31H 37H 37H 30H 33H 30H
S
T
X
E
T
X
30H+31H+31H+37H+37H+30H
=130H
User frame
(First frame)
User frame
(Last frame)
Arbitrary
data
User frame register
code
Sum
check
code
Station
No.
Read data
Transmission/
reception data code
Calculation range
011770 32
02H 30H
02H
03H
03H FFH+EBH
31H 31H 37H 37H 30H 33H 32H
S
T
X
02H+30H+31H+31H+37H+37H+30H
=132H
User frame
(First frame)
User frame
(Last frame)
Arbitrary data
User frame register
code
Sum
check
code
E
T
X
Station
No.
Read data
Transmission/
reception data code
Calculation range