Omron CP - PROGRAMMING MANUAL 05-2007 Programming Manual page 323

Data Shift Instructions
Description
Flags
Precautions
Note
Examples
3-8-10 DOUBLE ROTATE LEFT: ROLL(572)
Purpose
Ladder Symbol
290
ROL(027) shifts all bits of Wd including the Carry Flag (CY) to the left (from
rightmost bit to leftmost bit).
Name Label
Error Flag ER
Equals Flag =
Carry Flag CY
Negative Flag N
When ROL(027) is executed, the Error Flag will turn OFF.
If as a result of the shift the contents of Wd is zero, the Equals Flag will turn
ON.
If as a result of the shift the contents of the leftmost bit of Wd is 1, the Nega-
tive Flag will turn ON.
It is possible to set the Carry Flag contents to 1 or 0 immediately before exe-
cuting this instruction, by using the Set Carry (STC(040)) or Clear Carry
(CLC(041)) instructions.
When CIO 0.00 is ON, word CIO 1000 and the Carry Flag (CY) will shift one
bit to the left. The contents of CIO 1000.15 will be shifted to the Carry Flag
(CY) and the Carry Flag contents will be shifted to CIO 1000.00.
0.00
1000
Wd
Wd: CIO 1000
Shifts all Wd and Wd +1 bits one bit to the left including the Carry Flag (CY).
ROLL(572)
Wd
Operation
OFF
ON when the shift result is 0.
OFF in all other cases.
ON when 1 is shifted into the Carry Flag (CY).
OFF in all other cases.
ON when the leftmost bit is 1 as a result of the shift.
OFF in all other cases.
Instruction executed once
Wd: Word
Section 3-8