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UM012811-0904
eZ8 CPU Instruction Set Description
eZ8 CPU
User Manual
151
PUSH
Push
PUSH src
Operation
SP
←
SP - 1
@SP
←
src
Description
The Stack Pointer contents decrement by one. The source operand contents are loaded into
the location addressed by the decremented Stack Pointer, adding a new element to the
stack.
Flags
Attributes
Escaped Mode Addressing
Using Escaped Mode Addressing, address modes R or IR can specify a Working Register.
If the source address is prefixed by
EH
(1110B), a Working Register is inferred. For exam-
ple, if Working Register R12 (
CH
) is the desired source operand, use
ECH
as the source
operand in the opcode. To access Registers with addresses
E0H
to
EFH
, either set the
Working Group Pointer, RP[7:4], to
EH
or use indirect addressing.
C
Unaffected.
Z
Unaffected.
S
Unaffected.
V
Unaffected.
D
Unaffected.
H
Unaffected.
Mnemonic
Source
Opcode (Hex)
Operand 1
Operand 2
Operand 3
PUSH
R2
70
R2
—
—
PUSH
@R2
71
R2
—
—
PUSH
IM
1F70
IM
—
—