Mitsubishi Electric MELSEC iQ-R Series User Manual page 91

Receive data arrangement
The following shows the example of the arrangement of data received from the target device when it is stored in the receive
area.
• The received message is stored to the C24 buffer memory (Receive data storage area).
• The data is stored in the receive data storage area in the order of the data reception from low address, (L)  (H), to next
address, (L)  (H).
Ex.
When received data "ABCDEFG123" was stored (for the CH1 side)
C24
Reception area
(buffer memory)
5
Receive data count
(00 )
H
B
(42 )
H
D
(44 )
H
F
Received data
(46 )
H
1
(31 )
H
3
(33 )
H
When the data length unit is in bytes, 00H is stored in the higher byte of the last data storage position in the receive area when
the data length of the message is an odd byte.
(05 )
Data
H
A
length
A
(0005H)
(41 )
ENQ
H
C
L H
(43 )
H
05 00 41 42
H H H
E
(45 )
H
G
(47 )
H
Transmitted data (Response message)
2
(32 )
H
Received data
B C D E F G 1 2
43 44 45 46 47 31 32 33
H H H H H H H H
ACK
06
H
(Normal completion)
4 DATA COMMUNICATION USING BIDIRECTIONAL PROTOCOL
4.1 Receiving Data from Target Device
Sum
3
check
code
L H
77 02
H H H
Target device
4
89