What are the instructions in 8051?

A Brief Look at 8051 Microcontroller Instructions and Groups

How many instructions are there in 8051 microcontroller?

110 instructions
The microcontroller 8051 instructions set includes 110 instructions, 49 of which are single byte instructions, 45 are two bytes instructions and 17 are three bytes instructions. The instructions format consists of a function mnemonic followed by destination and source field. Data transfer group. Arithmetic group.

What is Lcall and Acall bytes instruction respectively?

ACALL is a 2-byte instruction, in contrast to LCALL which is 3 bytes. The target address of the subroutine must be within 2K bytes because only 11 bits of the 2 bytes are used for address.

What is Jnz in 8051?

The JNZ instruction transfers control to the specified address if the value in the accumulator is not 0. If the accumulator has a value of 0, the next instruction is executed. Neither the accumulator nor any flags are modified by this instruction.

Which of the following instruction is invalid?

Which of the following instruction is not valid? Explanation: Both the source and destination operands cannot be memory locations except for string instructions.

What is push and pop instruction in 8051?

When the 8051 is initialized, the SP register contains the value 07H. This means that the RAM location 08 is the first location used for the stack. The storing operation of a CPU register in the stack is known as a PUSH, and getting the contents from the stack back into a CPU register is called a POP.

What is DJNZ in 8051?

The DJNZ instruction decrements the byte indicated by the first operand and, if the resulting value is not zero, branches to the address specified in the second operand.

Why 8051 is called a Boolean processor?

Boolean Instructions. The 8051 processor contains a complete Boolean processor for single-bit operations. The internal RAM contains 128 addressable bits, and the SFR space supports up to 128 other addressable bits. All port lines are bit-addressable, and each can be treated as a separate single-bit port.

What is the instruction size of a call instruction?

The conditional call instructions are 3 Bytes in length, 1 Byte for the opcode, and another 2 Bytes for the subroutine address i.e.low-order Byte and high-Byte of the address values.

What is Jnz example?

In 8085 Instruction set, we are having one mnemonic JNZ a16, which stands for “Jump if Not Zero” and “a16” stands for any 16-bit address. This instruction is used to jump to the address a16 as provided in the instruction. But as it is a conditional jump so it will happen if and only if the present zero flag value is 0.

Which among the following is an example of unconditional jump instruction?

Conditional and Unconditional JUMP instructions in 8085 Microprocessor

Which of the following comes under the index addressing mode?

Indexed addressing mode stand for that instruction where the bits of accumulator are also indexed with the 16 bit registers. This discussion on Which of the following comes under indexed addressing mode? a)MOVX A, @DPTRb)MOVC @A+DPTR,Ac)MOV A,R0d)MOV @R0,ACorrect answer is option ‘B’.

What are the instructions in Section 1 8051?

Section 1 8051 Microcontroller Instruction Set For interrupt response time information, refer to the hardware description chapter. Note: 1. Operations on SFR byte address 208 or bit addresses 209-215 (that is, the PSW or bits in the PSW) also affect flag setti ngs. Instructions that Affect Flag Settings(1)

What are the different addressing modes in 8051?

E.g. CE, 8F which are called opcodes. Eg (In 8081) DEC A has opcode 14. Similarly, ADD A, R2 has opcode 2A. In 8051 there are different ways in which you can address or use these instructions. These are called addressing modes. In this addressing mode, the data is specified in the instruction itself.

What is the subroutine in the 8051 microcontroller?

1. Subroutine in 8051 Microcontroller By, Bhadresh Savani (140110120046) Ronak Sejani (140110120047) Aashiv Shah (140110120048) Guided by, B. R. Hindocha 2. What is Subroutine? Subroutine is a group of instructions Written separately from the main program to perform a function that occurs repeatedly in the main program.

What is the instruction set for Atmel 8051?

Atmel 8051 Microcontrollers Hardware 1 0509C–8051–07/06 Section 1 8051 Microcontroller Instruction Set For interrupt response time information, refer to the hardware description chapter. Note: 1. Operations on SFR byte address 208 or bit addresses 209-215 (that is, the PSW or bits in the PSW) also affect flag setti ngs.