Maxim Integrated MAXQ622 User Manual
Page 226
MAXQ612/MAXQ622 User’s Guide
16-16
Maxim Integrated
PUSH src
Push Word to the Stack
Description:
Increases the stack depth (decments the stack pointer SP) and pushes a single word specified by
src to the stack (@SP) .
Status Flags: None
Operation:
SP
← ++SP
Encoding:
15
0
f000
1101
ssss
ssss
Example(s):
PUSH GR
; GR=0F3Fh
PUSH #40h
Stack Data:
xxxxh
xxxxh
← SP (initial)
0F3Fh
← SP (after PUSH GR)
0040h
← SP (after PUSH #40h)
xxxxh
RET
Return from Subroutine
Description:
RET pops a single word from the stack (@SP) into the Instruction Pointer (IP) and decreases the stack
depth (increments the stack pointer SP) . The modified SP is saved as the new stack pointer (SP) .
Status Flags: None
Operation:
IP
← @SP--
Encoding:
15
0
1000
1100
0000
1101
Example(s):
RET
Code Execution:
Addr (IP)
Opcode
0311h
…
0312h
RET
→
0103h
…
Stack Data:
xxxxh
xxxxh
← SP (after RET)
0103h
← SP (before RET)
xxxxh
xxxxh