Computer Hardware User's Guide

RORC Rotate Right Through Carry
13-208
Syntax RORC dst
Operation dst right-rotated one bit through carry bit → dst
Operands dst register (R n , 0 ≤ n ≤ 27)
Opcode
31 24 23 16 8 7 015
000 10 1
1 00
dst
11 1111 11 1111111111
Description The contents of the dst operand are right rotated one bit through the status reg-
ister’s carry (C) bit. This could be viewed as a 33-bit shift. The carry bit value
is rotated into the MSB of the dst , while at the same time the dst LSB is rotated
into the carry bit.
Rotate right through carry bit:
dst C
Cycles 1
Status Bits These condition flags are modified only if the destination register is R7–R0.
LUF Unaffected
LV Unaffected
UF 0
N MSB of the output
Z 1 if a 0 output is generated; 0 otherwise
V 0
C Set to the value of the bit rotated out of the high-order bit; if
dst is not
R7 – R0, then C is shifted in but not changed
OVM Operation is not affected by OVM bit value.
Example RORC R4
Before Instruction After Instruction
R4 00 8000 0081 R4 00 4000 0040
LUF 0 LUF 0
LV 0 LV 0
UF 0 UF 0
N 1 N 0
Z 0 Z 0
V 0 V 0
C 0 C 1
Mode Bit