Omron CS1G/H-CPUxxH Instructions Manual page 390

Increment/Decrement Instructions
Flags
Precautions
Examples
The Equals Flag will be turned ON if the result is 0000 and the Carry Flag will
be turned ON when a digit changes from 0 to 9.
Name Label
Error Flag ER
Equals Flag =
Carry Flag CY
The content of Wd must be BCD. If it isn't BCD, an error will occur and the
Error Flag will be turned ON.
Operation of – –B(596)
In the following example, the BCD content of D00100 will be decremented by
1 every cycle as long as CIO 000000 is ON.
Wd: D00100
Operation of @– –B(596)
The up-differentiated variation is used in the following example, so the BCD
content of D00100 will be decremented by 1 only when CIO 000000 has gone
from OFF to ON.
@− −B
Wd: D00100
−1
Wd
ON if the content of Wd is not BCD.
OFF in all other cases.
ON if the content of Wd is 0000 after execution.
OFF in all other cases.
ON if a digit in Wd went from 0 to 9 during execution.
OFF in all other cases.
Decremented every cycle
while CIO 000000 is ON.
Wd: D00100
−1
: Execution of − −B(596)
Decrement Decrement Decrement Decrement
Decremented only
for up-differentiation.
Wd: D00100
−1
: Execution of @− −B(596)
Decrement Decrement
Section 3-10
Wd
Operation
369