Return from Subroutine
| Instruction | RET |
|---|---|
| Function | Return from subroutine |
| Bytes | 1 |
| Cycles | 2 |
| Encoding | 0 0 1 0 0 0 1 0 |
| Operation | PC15-8 = (SP) SP = SP - 1 PC7-0 = (SP) SP = SP - 1 |
| Description | RET pops the high- and low-order bytes of the PC successively from the stack, decrementing the Stack Pointer by two. Program execution continues at the resulting address, generally the instruction immediately following an ACALL or LCALL. No flags are affected. |
| Flags Affected | C AC F0 RS1 RS0 OV P |
| Example | The Stack Pointer originally contains the value 0BH. Internal RAM locations 0AH and 0BH contain the values 23H and 01H, respectively. The following instruction, RET leaves the Stack Pointer equal to the value 09H. Program execution continues at location 0123H. |
| Bytes: Number of bytes required to encode the instruction. Cycles: Number of instruction cycles required to execute the instruction. Note that there are 12 oscillator cycles to one instruction cycle on a standard 8051. Encoding: Lists the byte encoding for the instruction. Operation: Lists, step-by-step, the operations performed by the instruction. Flags Affected: are highlighted in Bold | |
Related topics:
8051 Program Branching Instructions | 8051 ACALL Instruction | 8051 LCALL Instruction | 8051 RETI Instruction | 8051 JMP Instruction | 8051 AJMP Instruction | 8051 LJMP Instruction | 8051 SJMP Instruction | 8051 JZ Instruction | 8051 JNZ Instruction | 8051 CJNE Instruction | 8051 DJNZ Instruction | 8051 NOP Instruction
List of topics: 8051
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