Z8
®
CPU
User Manual
UM001604-0108
Instruction Description
213
POP
Syntax
POP dst
Instruction Format
Operation
dst
←
@SP
SP
←
SP + 1
The contents of the location specified by the SP (Stack Pointer) are loaded into the desti-
nation operand. The SP is then incremented automatically.
Address modes R or IR can be used to specify a 4-bit Working Register. In this format, the
destination Working Register operand is specified by adding
1110b
(
Eh
) to the high nibble
of the operand. For example, if Working Register R12 (CH) is the destination operand, then
ECh
is used as the destination operand in the Op Code.
Example 1
If the SP (Control Registers
FEh
and
FFh
) contains the value
70h
and Register
70h
con-
tains
44h
, the statement:
POP 34h
Op Code: 50 34
loads the value
44h
into Register
34h
. After the POP operation, the SP contains
71h
. The
contents of Register 70 are not affected.
Cycles
OPC
(Hex)
Address Mode
dst
OPC
dst
10
50
R
10
51
IR
Flag
Description
C
Unaffected
Z
Unaffected
S
Unaffected
V
Unaffected
D
Unaffected
H
Unaffected
E
dst
Note: