Z8
®
CPU
User Manual
UM001604-0108
Instruction Description
231
Shift Right Arithmetic
Syntax
SRA dst
Instruction Format
Operation
C
←
dst(0)
dst(0)
←
dst(1)
dst(1)
←
dst(2)
dst(2)
←
dst(3)
dst(3)
←
dst(4)
dst(4)
←
dst(5)
dst(5)
←
dst(6)
dst(6)
←
dst(7)
dst(7)
←
dst(7)
An arithmetic shift right by one bit position is performed on the destination operand. Bit 0
replaces the C Flag. Bit 7 (the Sign bit) is unchanged and its value is shifted into bit 6, as
shown below.
Address modes R or IR can be used to specify a 4-bit Working Register. In this format, des-
tination Working Register operand is specified by adding
1110b
(Eh)
to the high nibble of
Cycles
OPC
(Hex)
Address Mode
dst
OPC
dst
6
D0
R
6
D1
IR
Flag Description
C
Set if the bit rotated from the least significant bit position was 1 (that is, bit 0 was 1).
Z
Set if the result is zero; cleared otherwise.
S
Set if the result bit 7 is set; cleared otherwise.
V
Always reset to 0.
D
Unaffected
H
Unaffected
C
D7 D6 D5 D4 D3 D2 D1 D0
Note: