INSTRUCTION SET

S3C84E5/C84E9/P84E9

 

 

RET — Return

RET

Operation: PC @SP

SP SP + 2

The RET instruction is normally used to return to the previously executed procedure at the end of the 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 to be executed is the one that is addressed by the new program counter value.

Flags: No flags are affected.

Format:

Bytes Cycles Opcode (Hex)

opc

Example: Given: SP

RET

1 10 AF

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

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

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Samsung S3C84E5 user manual RET Return, Operation PC ← @SP, Example Given SP, Ret →