Relative Addressing Mode
- In this mode, the operand is an relative address
- A relative address (or offset) is an 8-bit signed value, which is added to the program counter (PC) to form the address of the next instruction to be executed.
- This mode is used with short jump (SJMP) and conditional jump (JNZ) instructions
- Jump instructions are used to transfer control from one part of program to another
- Jump ahead and Jump back
- Destination address must be within -128 to +127bytes from current instruction address
- Advantage: position independent code
- Example: GoBack: DEC A
JNZ GoBack
The above instruction transfer the control back to previous instruction using relative address of previous instruction
Related topics:
8051 Addressing Modes | 8051 Register Addressing Mode | 8051 Direct Addressing Mode | 8051 Indirect Addressing Mode | 8051 Immediate Addressing Mode | 8051 Absolute Addressing Mode | 8051 Long Addressing Mode | 8051 Indexed Addressing Mode | 8051 External Addressing Mode
List of topics: 8051
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