Special Functions
Enable Interruption [EI], Disable Interruption [DI] and Interrupt Return [IRET]
EI
FEND
I0000
IRET
I0100
IRET
END
Limitation of interrupt bound》
《
EI
FEND
DI
Interruption
allow bound
Interruption①
Interruption②
z Normally PLC is in the status of
disable interruption, if use EI instruction
ption, then in the process
of scan the program, if interrupt input
changes from OFF to ON, then execute
int subroutine①、②, return to the
initial program after that.
z The pointer (I****) used as
interruption tag should be behind ,
FEND command.
of allow interru
errupt
Disable interruption
z Via DI instruction, you could set
interruption disabled area.
z In EI~DI area, interrupt input is
allowed.
z When don’t need interrupt disabled,
please program only with EI instruction,
needn’t program with DI instruction.
Allow Interruption
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