Mitsubishi MELSEC-Q/L - Recovery from Interrupt Programs

284
IRET
Function
(1) Indicates the completion of interrupt program processing.
(2) Returns to sequence program processing following the execution of the IRET instruction.
Operation Error
(1) In any of the following cases, an operation error occurs, the error flag (SM0) turns ON, and an error code is stored into
SD0.
Program Example
(1) The following program adds 1 to D0 if M0 is ON when the number 3 interrupt is generated.
[Ladder Mode] [List Mode]
6.6.2 IRET Recovery from i nterrupt programs
6.6.2 IRET
Setting
Data
Internal Devices
R, ZR
J\
U\G
Zn Constants Other
Bit Word Bit Word
–– ––
Error
code
Error details
Q00J/
Q00/
Q01
QnH QnPH QnPRH QnU LCPU
4220 There is no pointer corresponding to the interrupt number.
4221
After an interrupt occurred, the END, FEND, GOEND, or STOP
instruction was executed prior to the IRET instruction.
4223
The IRET instruction was executed before the interrupt program is
executed.
4223
The IRET instruction was executed during the fixed scan execution type
program.
–– –– –– ––
Basic
Process
High
performance
Redundant Universal LCPU
IRET
I
IRET
**
Step
Instruction
Device