user manual

8XC251SA, SB, SP, SQ USER’S MANUAL
A-112
PUSH <dest>
Function: Push onto stack
Description: Increments the stack pointer by one. The contents of the specified variable are then copied
into the on-chip RAM location addressed by the stack pointer.
Flags:
Example: On entering an interrupt routine, the stack pointer contains 09H and the data pointer
contains 0123H. After executing the instruction sequence
PUSH DPL
PUSH DPH
the stack pointer contains 0BH and on-chip RAM locations 0AH and 0BH contain 01H and
23H, respectively.
Variations
PUSH dir8
Binary Mode Source Mode
Bytes: 22
States: 44
Hex Code in: Binary Mode = [Encoding]
Source Mode = [Encoding]
Operation: PUSH
(SP) ← (SP) + 1
((SP)) ← (dir8)
PUSH #data
Binary Mode Source Mode
Bytes: 43
States: 43
Hex Code in: Binary Mode = [Encoding]
Source Mode = [Encoding]
Operation: PUSH
(SP) ← (SP) + 1
((SP)) ← #data
CY AC OV N Z
—————
[Encoding] 1 1 0 0 0 0 0 0 direct addr
[Encoding] 1 1 0 0 1 0 1 0 0 0 0 0 0 0 1 0 #data