6F3B0253
7. Instructions
FUN 140
EI
Enable interrupt
Expression
Input − [ EI ]− Output
Function
When the input is ON, this instruction enables the execution of user designated interrupt operation, i.e. timer interrupt program and I/O interrupt programs.
Execution condition
Input |
| Operation | Output |
OFF | No execution |
| OFF |
ON | Execution |
| ON |
Operand
No operand is required.
Example
In the above example, the DI instruction disables the interrupt. Then the EI instruction enables the interrupt again. As a result, the rung 2 instructions can be executed without interruption between each instructions.
Note
•Refer to the DI instruction (FUN 141).
•If an interrupt factor is occurred during the interrupt disabled state, the interrupt is kept waiting and it will be executed just after the EI instruction is executed.
•The EI instruction can be used only in the main program.
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