Omron CJ - REFERENCE MANUAL 02-2010 Reference Manual page 947

Precaution
• Only one network instruction may be executed for a communications port at one time. To ensure that
SEND(090) is not executed while a port is busy, program the port's Communications Port Enabled
Flag (A202.00 to A202.07) as a normally open condition.
• Refer to Automatically Allocating Communications Ports (i.e., Internal Logical Ports) on page 1115 for
details on using automatic allocation of the communications port number (logical port).
• Communications port numbers 00 to 07 are shared by the network instructions and PMCR(260), so
SEND(090) cannot be executed simultaneously with PMCR(260) if the instructions are using the
same port number.
• Noise and other factors can cause the transmission or response to be corrupted or lost, so we
recommend setting the number of retries to a non-zero value which will cause SEND(090) to be
executed again if the response is not received within the response monitoring time.
Example Programming
When CIO 0.00 and A202.07 (the Communications Port Enabled Flag for port 07) are ON in the
following example, the ten words from D100 to D109 are transmitted to node number 3 in the local
network where they are written to the ten words from D200 to D209. The data will be retransmitted up to
3 times if a response is not received within ten seconds.
0.00
A202.07
CS/CJ/NSJ Series Instructions Reference Manual (W474)
@SEND
D100
0
C: D300
D200
0
C+1: D301
D300
0
C+2: D302
C+3: D303 0
6
C+4: D304
Number of words to send: 10 words
Transmit to the local network and the device itself
Node number 3, unit address 00 (CPU Unit)
Response requested, port number 7, 3 retries
Response monitoring time: 0064 hexadecimal (10 seconds)
3. Instructions
3
911