POP
Pop Integer
13-194
Syntax
POP
dst
Operation
*SP– –
→
dst
Operands
dst register (Rn, 0
≤
n
≤
27)
Opcode
31
24 23
16
8 7
0
15
0 0 0
0 1
0
1
0
1
dst
1
0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Description
The top of the current system stack is popped and loaded into the
dst register
(32 LSBs). The top of the stack is assumed to be a signed integer. The POP
is performed with a postdecrement of the stack pointer. The exponent bits of
an extended-precision register (R7–R0) are left unmodified.
Cycles
1
Status Bits
These condition flags are modified only if the destination register is R7 – R0.
LUF
Unaffected
LV
Unaffected
UF
0
N
1 if a negative result is generated; 0 otherwise
Z
1 if a 0 result is generated; 0 otherwise
V
0
C
Unaffected
OVM
Operation is not affected by OVM bit value.
Example
POP R3
Before Instruction
After Instruction
R3
00 0000 12DA
R3
00 FFFF 0DA4
SP
809856
SP
809855
LUF
0
LUF
0
LV
0
LV
0
UF
0
UF
0
N
0
N
1
Z
0
Z
0
V
0
V
0
C
0
C
0
Data memory
809856h
FFFF0DA4
809856h
FFFF0DA4
4,826
–62,044
–62,044
–62,044
Mode Bit