Delta Electronics Programmable Logic Controller DVP-PLC - Manual (Page 221)

6 Application Instructions API 00-49
DVP-PLC Application Manual 6-9
3. In the program, using interruption subroutine between EI and DI instruction is allowed. However, you can
choose not to use DI instruction if there is no interruption-disabling section in the program.
4. When M1050 ~ M1059 are the special auxiliary relays to drive disabling interruption in ES/SA, or M1280 ~
M1299 are the special auxiliary relays to drive disabling interruption in EH/EH2/SV, the corresponding
interruptions will not be executed even in the area allowed for interruptions.
5. Pointer for interruption (I) must be placed after FEND instruction.
6. Other interruptions are not allowed during the execution of interruption subroutine.
7. When many interruptions occur, the priority is given to the firstly executed interruption. If several interruptions
occur simultaneously, the priority is given to the interruption with the smaller pointer No.
8. The interruption request occurring between DI and EI instructions that cannot be executed immediately will be
memorized and will be executed in the area allowed for interruption.
9. The time interruptions in ES/SA will not be memorized.
10. When using the interruption pointer, DO NOT repeatedly use the high-speed counter driven by the same X input
contact.
11. When immediate I/O is required during the interruption, write REF instruction in the program to update the status
of I/O.
Program Example:
During the operation of PLC, when the program scans to the area between EI and DI instructions and X1 = Off→On
or X2 = Off→On, interruption subroutine A or B will be executed. When the subroutine executes to IRET, the program
will return to the main program and resumes its execution.
I 101
I 201
Y1
EI
FEND
X0
DI
IRET
IRET
Y0
Y0
EI
Disable interruption
Enable interruption
Enable interruption
Interruption subroutine A
Interruption subroutine B
Remarks:
1. No. of interruption pointer I in ES/EX/SS:
a) External interruptions: (I001, X0), (I101, X1), (I201, X2), (I301, X3) 4 points 2 .
b) Time interruptions: I6□□, 1 point (□□ = 10 ~ 99, time base = 1ms) (support V5.7 and above)
2 Input points occupied by external interruptions cannot be used for inputs of high-speed counters; otherwise grammar check errors may occur
when the program is written in PLC.