Omron CJ1W-SCU32 Operation Manual page 398

A Standard System Protocol
Loopback Test
(Sequence No. 818 (Hex 0332)) (Command Code: TT)
This sequence executes a loopback test at the Mitsubishi Computer Link Module with the specified sta-
tion number (and the PLC number that follows). (E.g, if the data starting from the specified word + 3 is
sent from the host, the Computer Link Module will return the data unchanged to the host.)
Send Data Word Allocation (3rd Operand of PMCR(260))
First word of
send data
Offset
+0 Number of send data words (4 digits hex)
+1 Station No.
(2 digits hex)
+2 (Undefined)
+3 Loopback data
on
Receive Data Word Allocation (4th Operand of PMCR(260)
Receive data
storage words
Offset
+0 Number of receive data words
+1 Station No.
(2 digits hex)
+2 Data length
(2 digits hex)
+3 Loopback data
on
R-64
Number of send data words
+0
+1
Station No. PLC No.
+2
(Undefined) Data length
+3 Loopback data
on
Contents (data format)
PLC No.
(2 digits hex)
Data length
(2 digits hex)
Number of receive data words
+0
+1
Station No. PLC No.
+2
Data length
+3 Loopback data
on
Contents (data format)
PLC No.
(2 digits hex)
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Data
Always 0005 hex (5 decimal)
Station No.: 00 to FF hex
PLC No.: 00 to FF hex
Set the number of bytes of loopback data in S+3
onwards.
Set the loopback data to send.
Data
0002 to 00FA hex (2 to 250 decimal)
Station No.: 00 to FF hex
PLC No.: 00 to FF hex
The data length for the loopback data is stored.
The loopback data is stored unchanged.