Omron NX102-10 Series, User Manual

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Related System-defined Variables
Name Meaning
Data
type
Description
_Port_numUsingPort
Number of Used
Ports
USINT This is the number of ports that are currently used.
_Port_isAvailable
Network Communi-
cations Instruction
Enabled Flag
BOOL
TRUE: A port is available.
FALSE: A port is not available.
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 . When the instruction is executed, 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 , it is recommended to retry the process.
• 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. If this instruction is not executed every task pe-
riod, the normal process may not be performed.
• This instruction cannot be used on the event task. An error occurs during compiling.
• An error occurs 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.
3 Client Function
3 - 16
NX-series CPU Unit FINS Function User's Manual (W596)