Omron SYSMAC CJ1W-SCU21-V1, Operation Manual

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Communications Frames Section 6-8
connected serially via Host Link to another PLC on the network (to which
the Serial Communications Board/Unit is mounted) using the SEND(090)/
RECV(098) instructions is the same as for the CMND(490) instruction.
2. When creating Host Link FINS command frames using the CMND(490) in-
struction, always set the unit number for Host Link incremented by one (1
to 32) for the remote destination (send destination) node address (word
C+3, bits 08 to 15 of the CMND(490) instruction). Do not set the unit num-
ber of the actual Host Link slave (0 to 31). Using the Host Link unit number
without incrementing by one will access the PLC with the entered Host Link
unit number less one.
For example, specify remote PLC with Host Link unit number 2 by entering
3 for the remote destination node address. If the 2 is entered, the PLC with
Host Link unit number 1 will be accessed.
To access a PLC on a Host Link FINS network using the Serial Gateway
from CX-Programmer, however, enter the actual Host Link unit number,
without incrementing by one. (Select
Change PLC , click the Display Seri-
al Gateway Guide Button, and set unit number in the Host Link SYSWAY
Settings field of the Serial Gateway Guide dialog box.
Sending Modbus-ASCII Commands
• Set the FINS command code of 2805 hex in S, indicating conversion to
Modbus-RTU.
• In S+1 onwards, set the slave address (2 bytes ASCII) + FUNCTION code
(2 bytes ASCII) + communications data (2
×
n bytes ASCII) from leftmost
bytes to rightmost bytes using ASCII.
Sending CompoWay/F Commands
• Set the FINS command code of 2803 hex in S, indicating conversion to
CompoWay/F.
• In S+1 onwards, set the CompoWay/F node number (2 bytes ASCII) +
sub-address (2 bytes ASCII) + SID (1 byte ASCII) + CompoWay/F com-
mand MRC (2 bytes ASCII) + CompoWay/F command SRC (2 bytes
ASCII) + text (2
×
n bytes ASCII) from leftmost bytes to rightmost bytes
using ASCII.
Note Set the contents of S+3 when using CompoWay/F commands as follows:
Set the SID “0” as ASCII 30 hex (1 byte) in the leftmost byte, and the leftmost
digit of the CompoWay/F command code MRC as ASCII (1 byte) in the right-
most byte. Next, set the bits of S+4 as follows:
Set the rightmost digits of the CompoWay/F command code MRC as ASCII in
the leftmost byte, and the leftmost digit of the CompoWay/F command code
SRC as ASCII (1 byte) in the rightmost byte. Be sure to set one byte each for
the subsequent data without any blank bytes.