2 Instructions
2-48 CP1E CPU Unit Instructions Reference Manual(W483)
Operation of Differentiated Instructions in an MILR(518) Interlock
If there is a differentiated instruction (DIFU, DIFD, or instruction with a @ or % prefix) between
MILR(518) and the corresponding MILC(519), that instruction will not be executed after the interlock is
cleared even if the differentiation condition of the instruction was established.
In the same way, a differentiated instruction will not be executed if its execution condition is established
at the same time that the interlock is started or cleared.
Example
When a DIFFERENTIATE UP (DIFU(013)) instruction is being used and the input condition is OFF
when the interlock starts and ON when the interlock is cleared, DIFU(013) will not be executed when
the interlock is cleared.
Controlling Interlock Status from a Programming Device
An interlock can be engaged or released manually by force-resetting or force-setting the Interlock Sta-
tus Bit (specified with operand D of MILH(517) and MILR(518)) from a Programming Device. The forced
status of the Interlock Status Bit has priority and overrides the interlock status calculated by program
execution.
Timing chart
Force-set: Releases the interlock. Force-reset: Engages the interlock.
MILR
0
MILC
0
DIFU
W0.0
0.00
0.01
1. When CIO 0.00 is OFF (interlock starts), the DIFU,s CIO 0.01 input condition is OFF.
2. The DIFU,s CIO 0.01 input condition goes from OFF to ON while CIO 0.00 is OFF (DIFU interlocked),
3. When CIO 0.00 goes from OFF to ON (interlock cleared), DIFU is not executed even though CIO 0.01 is still ON.
ON
0.00
0.01
W0.0
OFF
OFF
ON ON
OFF
ON
OFF
DIFU(013) is not executed.
MILR(518) interlock
Not interlocked Interlocked Not interlocked
OFF
MILC
n
MILH
n
100.00
If CIO 100.00 is force-set (ON), the interlock is released.
CIO 100.00 is OFF when the interlock is engaged.
Program section
controlled by interlock
MILC
n
ON
MILH
n
100.00
If CIO 100.00 is force-reset (OFF), the interlock is engaged.
CIO 100.00 is ON when the interlock is not engaged.
Program section
controlled by interlock