INSTRUCTION SET

S3F80JB

 

 

RET — Return

RET

Operation: PC @SP

SP SP + 2

The RET instruction is normally used to return to the previously executing procedure at the end of a procedure entered by a CALL instruction. The contents of the location addressed by the stack pointer are popped into the program counter. The next statement that is executed is the one that is addressed by the new program counter value.

Flags:

No flags are affected.

 

 

 

Format:

 

 

 

 

 

 

 

 

 

 

Bytes

Cycles

Opcode (Hex)

 

 

opc

 

1

8 (internal stack)

AF

 

 

 

 

 

10 (internal stack)

 

Example: Given: SP = 00FCH, (SP) = 101AH, and PC = 1234:

RET

PC = 101AH, SP = 00FEH

The statement "RET" pops the contents of stack pointer location 00FCH (10H) into the high byte of the program counter. The stack pointer then pops the value in location 00FEH (1AH) into the PC's low byte and the instruction at location 101AH is executed. The stack pointer now points to memory location 00FEH.

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Samsung S3F80JB manual RET Return, Operation PC ← @SP, PC = 101AH, SP = 00FEH