GE VersaMax PLC User Manual page 154

Input/
Output
enable
IN
SYSID
TASK
FT
154 GFK-1503E
For public disclosure
10.3.5.1 Parameters of the COMMREQ Function
Choices
When the function is energized, the
flow
communications request is performed.
R, AI, AQ
IN contains the first word of the command block.
SYSID contains the rack number (most
I, Q, M, T, G, R, AI, AQ,
significant byte) and slot number (least
constant
significant byte) of the target device.
TASK contains the task ID of the process on the
R AI, AQ, constant
target device.
FT is energized if an error is detected processing
the COMM REQ:
(SYSID).
flow, none
(TASK).
command block) does not exist.
10.3.5.2 Command Block for the COMMREQ Function
The Command Block starts at the reference specified in COMMREQ parameter IN. The
length of the Command Block depends on the amount of data sent to the device.
The Command Block contains the data to be communicated to the other device, plus
information related to the execution of the COMM REQ. The Command Block has the
following structure:
address
address + 1
address + 2
address + 3
address + 4
address + 5
address + 6 to
address + 133
Description
1. The specified target address is not present
2. The specified task is not valid for the device
3. The data length is 0.
4. The device's status pointer address (in the
Length (in words)
Wait/No Wait Flag
Status Pointer Memory
Status Pointer Offset
Idle Timeout Value
Maximum Communication Time
Data Block
VersaMax PLC User Manual