Chapter 9 XGATE (S12XGATEV2)
MC9S12XDP512 Data Sheet, Rev. 2.11
Freescale Semiconductor 447
Operation
n = RS or IMM4
Shifts the bits in register RD n positions to the right. The higher n bits of the register RD become filled
with the carry flag. The carry flag will be updated to the bit contained in RD[n-1] before the shift for n>0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, nis determined by the content of RS. nis considered to be 16 if the content of RS
is greater than 15.
CCR Effects
Code and CPU Cycles
CSR Logical Shift Right with Carry CSR
NZVC
∆∆∆∆
N: Set if bit 15 of the result is set; cleared otherwise.
Z: Set if the result is $0000; cleared otherwise.
V: Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
C: Set if n > 0 and RD[n-1] = 1; if n = 0 unaffected.
Source Form Address
Mode Machine Code Cycles
CSR RD, #IMM4 IMM4 0 0 0 0 1 RD IMM4 1 0 1 1 P
CSR RD, RS DYA 0 0 0 0 1 RD RS 1 0 0 1 1 P
C C
RD
CC
n bits
C
n