Instruction set of 8051 Microcontrollers

8051 instruction set

1. Instruction Set of 8051 Sushil Karvekar Walchand College of Engineering Sangli

2. Special Function Registers 8051 has 21 Special Function Registers Address of SFRs : 80H to FFH Some SFRs are both bit addressable and byte addressable Eg : T0CON , T1CON, SMOD, etc

3. Instruction Set of 8051 MUL AB : Performs multiplication of contents in A and B registers Stores the 16 bit result in registers A(lower byte) and B(higher byte) DIV AB: Divides content of A by B Result=> Quotient in A and Remainder in B

4. Types of Instruction Sets Arithmetic Logical Data Transfer Boolean variable Program Branching

5. Arithmetic Intructions Execute in one machine cycle Except INC (Two Machine Cycles) MUL AB and DIV AB (4 machine cycles)

6. Notations Rn: One of the working registers R0 to R7 A : Accumulator @ Ri : Indirect Registers R0 or R1 Direct :8-bit address of RAM #data : immediate data Addr16 : 16-bit Address

7. Arithmetic Instructions

8. Logical Instructions

9. Bit Related Instructions

10. Data Copy Instructions

11. Jump Related Instructions