Instruction Status
You can check the error status with the system variable #L_ExIOSpParmErr (special I/O parameter error).
31.5.1.3 Special I/O System Variables
Enabling condition
While the instruction is in operation and the parameter read has been completed
If no error has occurred (refer to the following notes).
Disabling condition
While the instruction is in operation and when it has been confirmed that the parameter read completion flag is cleared.
(Parameter read request is canceled and the parameter read completion flag is cleared.)
*When disabled, the operand D1 is cleared to 0.
Notes
While executing the instruction, any parameter reads are monitored. If it is being read, an error occurs and no process will be performed.
When the operand D1 cannot be recognized in the instruction, an error occurs.
When executing the instruction using the pulse (for example, PT instruction), you need to turn the instruction OFF and then turn it ON to execute it again.
When the instruction is executed, it will be in operation.
If the instruction is in operation, the instruction will be executed continuously regardless of the enabling/disabling condition.
If you are using the LT4000 series, and would like to use two synchronize outputs for High Speed Counters (2 phase), you must add one HSCG instruction for each output. In this case, the preload value of the HSCG instruction for CH2 will be invalid.