3
- 22
3.1 Sequence Program
3.1.3 Interrupt programs
3
SEQUENCE PROGRAM CONFIGURATION AND
EXECUTION CONDITIONS
(7) Restrictions on programming
Restrictions on interrupt programming will be explained.
(a) Device turned ON/OFF by instruction such as PLS
When using an instruction such as PLS, by which an execution condition turns ON
from OFF in the next step and it turns the operation device ON, the device
remains ON until the same instruction is executed.
When using an instruction such as PLF, by which an execution condition turns
OFF from ON in the next step and it turns the operation device ON, the device
remains ON until the same instruction is executed.
(b) EI/DI instruction
During execution of an interrupt program, interrupts are disabled (DI) so that any
other interrupt processing will not be executed.
Do not execute the EI/DI instruction during interrupt program execution.
(c) Timers (T) and counters (C)
Timers and counters are not available for interrupt programs.
The timers (T) and counters (C) update the current values and turn ON/OFF the
contacts when the OUT T and OUT C instructions are executed, respectively.
Using a timer (T) and/or a counter (C) in an interrupt program update the current
value only during execution of the interrupt program.
Do not use them since measurement cannot be made correctly.
(d) Instructions not available for interrupt programs
For instructions not available in interrupt programs, refer to each instruction of
programming manual.
Figure 3.17 Device turned ON by PLS in interrupt program
X0
OFF
ON
M0
OFF
ON
END
0
I0
IRET END 0
END
0 I0
IRET
END
0
PLS M0
X0
PLS M0
X0
Turned OFF when PLS M0
instruction is executed.
Turned ON when PLS M0 instruction is executed on
leading edge (OFF ON) of X0.
Содержание Q00CPU
Страница 1: ......
Страница 2: ......
Страница 972: ...Index 6 Memo ...
Страница 975: ......
Страница 976: ......