Omron CJ - REFERENCE MANUAL 10-2009 Reference Manual page 913

Execution Timing of Network Communications Instructions
When the execution condition for a Network Communications Instruction is ON, processing
communications is started, but actual communications are processed in the background using
peripheral servicing.
Execution
Communications Port
condition
Enabled Flag
The following operation occurs.
(1) If the relevant Communications Port Enabled Flag (A202.00 to A202.07) is ON when the execution
condition turns ON, it turns OFF, the Communications Port Error Flag (A219.00 to A219.07) turns
OFF, the Communications Port Completion Codes (A203 to A210) is cleared to 0000 hex, the
contents of the control words starting from C are read, and communications processing (sending
the FINS command and receiving the response) is started.
(2) The communications command is processed during peripheral servicing. This processing lasts for
the required number of cycles.
(3) When a response is received, the response words specified by the operand are updated in
communications port servicing. The Communications Port Enabled Flag (A202.00 to A202.07) is
turned ON, the Communications Port Error Flag (A219.00 to A219.07) is turned ON or OFF
according to the results of the instruction, and the Communications Port Completion Code (A203 to
A210) is stored.
Cycle time, 1st cycle
User program executed
END
executed
(1) SEND/SEND2,
RECV/RECV2, or
CMND/CMND2
executed
(2) Communications (creating
and sending FINS
command) are processed
during communications
servicing time.
CS/CJ/NSJ Series Instructions Reference Manual (W474)
Specifies only
the start of
processing
CMND
S
D
C
The results are
stored when processing
communications has been
completed.
(3) Executed over
several cycles
I/O refresh
Peripheral
servicing
Command sent
Background processing of communications
Cycle
time
Cycle
time
Cycle time, 2nd cycle and later
User program executed
END
executed
I/O refresh
(4) Communications (receiving
response) are processed during
communications servicing time.
3. Instructions
FINS command built
from command data and
then sent.
Communications (sending and
receiving) is processed during the
communications port service time
in peripheral servicing over multiple
cycles using time slicing.
The response is received and
stored as response data. The
results of communications is
shown in the Auxiliary Area flags.
Peripheral
servicing
Response received
875
3