Omron CP - PROGRAMMING MANUAL 05-2007 Programming Manual page 902

Network Instructions
Precautions
Example 1
The following table shows relevant bits and flags in the Auxiliary Area.
Name Address
Communications A202.00 to
Port Enabled Flag A202.07
Communications A219.00 to
Port Error Flag A219.07
Communications A203 to
Port Completion A210
Codes
If the Communications Port Enabled Flag is OFF for the port number specified
in C+3, the instruction will be treated as NOP(000) and will not be executed.
The Error Flag will be turned ON in this case.
When an address in the current bank of the EM Area is specified for D, the
transmitted data will be written to the current EM bank of the destination node.
When data will be transmitted outside of the local network, the user must reg-
ister routing tables in the PLCs (CPU Units) in each network. (Routing tables
indicate the routes to other networks in which destination nodes are con-
nected.)
Refer to the FINS command response codes in the CS/CJ/CP Series Com-
munications Commands Reference Manual (W342) for details on the comple-
tion codes for network communications.
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, pro-
gram the port's Communications Port Enabled Flag (A202.00 to A202.07) as
a normally open condition.
Communications port numbers 00 to 07 are shared by the network instruc-
tions 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 cor-
rupted 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.
When the input condition and A202.00 (the Communications Port Enabled
Flag for port 7) are ON in the following example, the ten words from CIO 100
to CIO 109 are transmitted to the host computer connected to port 1 of the
CJ-series Serial Communications Unit with unit address 10 (hex) at node
number 3 in network 0.
Operation
These flags are turned ON to indicate that net-
work instructions, including PMCR(260) may be
executed for the corresponding ports (00 to 07).
A flag is turned OFF when a network instruction is
being executed for the corresponding port and
turned ON again when the instruction is com-
pleted.
These flags are turned ON to indicate that an
error has occurred at the corresponding ports (00
to 07) during execution of a network instruction.
The flag status is retained until the next network
instruction is executed. The flag will be turned
OFF when the next instruction is executed even if
an error occurred previously.
These words contain the completion codes for the
corresponding ports (00 to 07) following execution
of a network instruction.
The corresponding word will contain 0000 while
the network instruction is being executed and the
completion code will be written when the instruc-
tion is completed. These words are cleared when
an instruction is executed.
Section 3-24
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