Omron CJ1W-SCU32 Operation Manual page 361

Receive Data Word Allocation (4th Operand of PMCR(260))
Receive data
storage words
Offset
+0 Number of receive data words
+1 Response code (4 digits hex)
+2 Receive data (4 digits hex)
on
The received frames are stored in order from the leftmost word to the rightmost word of the I/O
memory address.
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
+0
Number of receive data words
+1
Response code
+2
Receive data
on
Contents (data format)
Receive frame
"12" "34" "56" "78"
A Standard System Protocol
0003 to 00FA Hex (3 to 250 decimal)
The CompoWay/F command response code is
stored in hexadecimal code.
The read data is stored.
Receive data words
5 6 7 8 Rightmost word
1 2 3 4 Leftmost word
Data
R-27