Intel 210200-002 manual Rotate Right ROR, ROR destination, count

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ROR

ROTATE RIGHT ROR

Operation:	Flags Affected:
(temp)- COUNT	CF,.OF
do while (temp) "* 0
(CF) - low-order bit of (EA)

,(EA) - (EA) I 2

high-order bit of (EA) - (CF)

(temp) - (temp)-1 if COU NT = 1 then

if high-order bit of (EA) "* next- to-high-order bit of (EA)

then (OF)-1 else (OF) - 0

else (OF) undefined

Description:

ROR destination, count

ROR (Rotate Right) operates similar to ROL except that the bits in the destination byte or word are rotated right instead of left.

Encoding:

11101 00 v w 1mod 001 rIm 1

if v = 0 then COUNT = 1 else COUNT = (CL)

ROR Operand	Clocks*	Transfers	Bytes	ROR Coding Example
register, 1	2	-	2	ROR AL, 1
register, CL	8+ 4/bit	-	2	ROR BX, CL
memory, 1	15(23) +EA	2	2-4	ROR PORT_STATUS, 1
memory, CL	20(28) +EA +41 bit	2	2-4	ROR CMD_WORD, CL

*b(w): where b denotes the number of clock cycles for byte operands and w denotes the number of clock cycles for word operands.

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