Omron NX502-1 Series User Manual page 54

3 Client Function
Related System-defined Variables
Name
_Port_numUsingPort
_Port_isAvailable
Precautions for Correct Use
• This instruction can be executed only when there is an available port. Therefore, use the system-
defined variable _Port_isAvailable (Network Communications Instruction Enabled Flag) in an N.O.
execution condition for the instruction.
• The command is not sent if the value of CmdSize is 0. In thar case, the value of Done changes to
TRUE.
• During execution of this instruction, set Option.Retry to a value other than 0 by considering the case
when the send message or response is lost due to noise that occurs during communication. If no
response is returned within Option.TimeOut, try to resend the message.
• Refer to the CS/CJ/CP/NSJ-series Communications Commands Reference Manual (Cat. No. W342)
for specification of network address.
The FINS routing specification in the NX-series CPU Units differ from those in the CS/CJ-series
CPU Units.
Refer to A-1 Difference Between CS/CJ-series and NX-series in FINS Routing on page A-2 for
information on differences in routing specification.
• When this instruction is written in the ST program, make sure that the instruction is executed for
each task period during execution of this instruction. Otherwise, normal processing may not be pos-
sible.
• You cannot use this instruction in an event task. A compiling error will occur.
• An error will occur in the following cases. Error will change to TRUE.
a) A member of DstNetAdr is outside of its range.
b) CmdSize is outside of its range.
c) The value of CmdSize exceeds the size of CmdDat[].
d) A member of Option is outside of its range.
e) The response size exceeds the size of RespDat[].
f) The value of _Port_isAvailable is FALSE.
g) Communications fail.
h) The Do not use option is selected for FINS/UDP and FINS/TCP connection has not been estab-
lished.
• If the value of Error code "Error ID" is WORD#16#0800, the expansion error code "ErrorIDEx" has
the meaning of end code for the communication command in this instruction.
Refer to End Codes in 5-1 Command Lists of the SYSMAC CS/CJ/CP/NSJ-series Communications
Commands Reference Manual (Cat. No. W342) for details.
3-16
Data
Meaning
type
Number of Used
USINT
Ports
Network Communi-
cations Instruction BOOL
Enabled Flag
Description
This is the number of ports that are currently used.
TRUE: A port is available.
FALSE: A port is not available.
NX-series CPU Unit FINS Function User's Manual (W596)