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PULD
Operation:
(M
(SP)
(SP) + $0002 ⇒ SP
Description:
Double accumulator D is loaded from the address indicated by the stack
pointer. The SP is then incremented by two.
The order in which A and B are pulled from the stack is the opposite of
the order in which A and B are pulled when an RTI instruction is execut-
ed. The interrupt stacking order for A and B is backward-compatible with
the M6800, which had no 16-bit accumulator.
Pull instructions are commonly used at the end of a subroutine, to re-
store the contents of CPU registers that were pushed onto the stack be-
fore subroutine execution.
Condition Codes and Boolean Formulas:
S
–
None affected.
Addressing Modes, Machine Code, and Execution Times:
Source Form
PULD
CPU12
REFERENCE MANUAL
Pull Double Accumulator
from Stack
) ⇒ A : B
: M
(SP + 1)
X
H
I
N
Z
–
–
–
–
–
Address Mode
INH
3A
INSTRUCTION GLOSSARY
V
C
–
–
Object Code
PULD
Cycles
Access Detail
3
UfO
MOTOROLA
6-163
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