8051 Instruction Set
- 8051 instruction set is optimized for 8-bit control applications
- 8051 instructions have 8-bit opcodes
- 28 = 256 instructions
- 255 instructions are implemented
- 1 instruction is undefined
- 139 1-byte instructions
- 92 2-byte instructions
- 24 3-byte instructions
- Instruction is made up of an operation code (op-code) followed by either zero, one or two bytes of operands
- The op-code identifies the type of operation to be performed while the operands identify the source and destination of the data
- Operand can be - The data value itself
- If the instruction is associated with more than one operand, the format is always: - Instruction Destination, Source
- Where does the data for an instruction come from? - Addressing Modes
- Supports the following addressing modes - Register, Direct, Indirect, Immediate, Relative, Absolute, Long, Indexed
- Instructions are divided into five groups - Arithmetic
- A CPU register
- A memory location
- An I/O port
- Logical
- Data Transfer
- Boolean Variable
- Program Branching
Related topics:
8051 Instruction Cycle | 8051 Machine Cycle | 8051 Instruction Set Summary | 8051 Arithmetic Operation Instructions | 8051 Logical Operation Instructions | 8051 Data Transfer Instructions | 8051 Boolean Variable Manipulation Instructions | 8051 Program Branching Instructions | 8051 Instruction Opcode | 8051 Instructions that Affect Flag Settings | 8051 Instructions and Examples
List of topics: 8051
No comments:
Post a Comment