Interrupt Program - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

1.7

Interrupt Program

A program from an interrupt pointer (I) through the IRET instruction.
Main routine program
Interrupt program (I0)
Interrupt program (I29)
*1 Only one interrupt program can be created with a single interrupt pointer number.
*2 The interrupt pointers are not required to be defined in an ascending order.
When an interrupt factor occurs, the interrupt program corresponding to its interrupt pointer number is executed ( Page
364 The priority for the interrupt pointer numbers and interrupt factors). However, before that, interrupt must be enabled by
using the EI instruction.
Execution
Main routine program
Interrupt program (I0)
Interrupt program (I29)
I0: Interrupt factor for I0
I29: Interrupt factor for I29
Making a program a standby type allows it to be managed as a separate program. ( Page 63 Standby
type program)
(1) This indicates the end of the main routine program.
EI
(1)
FEND
I0
IRET
I29
IRET
END
*1*2
Interrupt pointer
I0
Execution
Execution
IRET
I29
Execution
Execution
IRET
Time
1 RUNNING A PROGRAM
1.7 Interrupt Program
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