Ret -21, Ret c/ret nc, ret z/ret nz, ret s -21 – Maxim Integrated MAXQ7666 User Manual
Page 358
MAXQ7665/MAXQ7666 User’s Guide
14-21
RET
Return from Subroutine
Description:
RET pops a single word from the stack (@SP) into the Instruction Pointer (IP) and decrements the stack pointer (SP).
The decremented SP is saved as the new stack pointer (SP).
Status Flags:
None
Operation:
IP
← @ SP--
Encoding:
15
0
Example(s):
RET
Code Execution:
Stack Data:
← SP (before RET)
← SP (after RET)
RET C/RET NC
Conditional Return on Status Flag
RET Z/RET NZ
RET S
Description:
Performs conditional return (RET) based upon the state of a specific processor status flag. RET C returns if the Carry
flag is set while RET NC returns if the Carry flag is clear. RET Z returns if the Zero flag is set while RET NZ returns if
the Zero flag is clear. RET S returns if the Sign flag is set. See RET for additional information on the return operation.
Status Flags:
None
RET C
C=1: IP
← @SP--
Operation:
C=0: IP
← IP + 1
Encoding:
15
0
Example(s):
RET C
; C=1, return (RET) is performed
1010
1100
0000
1101
1000
1100
0000
1101
Addr (IP)
Op Code
0311h
• • •
0312h
RET
0103h
• • •
xxxxh
xxxxh
0103h
xxxxh
xxxxh
Maxim Integrated