INSTRUCTION DESCRIPTIONS
A - 264 INSTRUCTION SET DETAILS
MOTOROLA
Assembler Syntax:
ROR D (parallel move)
Description:
Rotate bits 47–24 of the destination operand D one bit to the right and
store the result in the destination accumulator. Prior to instruction execution, bit 24 of D
is shifted into the carry bit C, and, prior to instruction execution, the value in the carry bit
C is shifted into bit 47 of the destination accumulator D. This instruction is a 24-bit opera-
tion. The remaining bits of the destination operand D are not affected.
Example:
:
ROR B1#$1234,R2 ;rotate B1 right one bit, update R2
:
Explanation of Example:
Prior to execution, the 56-bit B accumulator contains the
value $00:000001:222222. The execution of the ROR B instruction shifts the 24-bit value
in the B1 register one bit to the right, shifting bit 24 into the carry bit C, rotating the carry
bit C into bit 47, and storing the result back in the B1 register.
ROR Rotate Right ROR
47 24
C(parallel move)
Operation:
Before Execution After Execution
B B
$00:000001:222222
SR SR
$0300 $0305
$00:000000:222222