Samsung KS57C2308 Manual page 147

KS57C2308/P2308/C2316/P2316
PUSH
— Push Onto Stack
PUSH src
Operation: Operand
RR
SB
Description: The SP is then decreased by two and the contents of the source operand are copied into the
RAM location addressed by the stack pointer, thereby adding a new element to the top of the
stack.
Operand
RR
SB
Example: As an interrupt service routine begins, the stack pointer contains the value 0FAH and the data
pointer register pair HL contains the value 20H. The instruction
PUSH
leaves the stack pointer set to 0F8H and stores the values 2H and 0H in RAM locations 0F9H
and 0F8H, respectively.
Operation Summary
Push register pair onto stack
Push SMB and SRB values onto stack
Binary Code
0 0 1
1 1 0
0 1 1
HL
0 1 r2 r1 1
1 1 1 0 1
0 0 1 1 1
SAM47 INSTRUCTION SET
Bytes
1
2
Operation Notation
(SP–1) RR , (SP–2)
H
SP SP–2
(SP–1) SMB, (SP–2)
(SP) SP–2
Cycles
1
2
RR
L
SRB;
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