8051 Microcontroller Quiz

Which instruction is used to transfer data from the accumulator to register R1?

• MOV A, R1

• MOV R1, A

• ADD A, R1

• SUBB R1, A

What is the function of the CPL instruction in the 8051 microcontroller?

• Complements the carry flag

• Complements the accumulator

• Shifts the bits of the accumulator to the left

• Sets all bits in the accumulator to 1

Which of the following instructions is used to perform logical AND between the accumulator and a direct address?

• ANL A, direct

• ORL A, direct

• XRL A, direct

• MOV A, direct

What is the purpose of the SJMP instruction in the 8051 microcontroller?

• Performs a short jump within the program memory

• Subtracts a jump address from the program counter

• Jumps to an absolute address in program memory

• Skips the next instruction if a condition is true

Which instruction is used to decrement the value in register R0 by 1?

• DEC A

• DEC R0

• INC R0

• SUBB R0, #01H

What does the NOP instruction do in the 8051 microcontroller?

• Stops the microcontroller for 1 clock cycle

• Performs no operation and skips to the next instruction

• Clears the accumulator

• Resets the program counter

Which addressing mode allows the operand to be part of the instruction itself?

• Direct Addressing

• Indirect Addressing

• Immediate Addressing

• Indexed Addressing

In which addressing mode is the address of the operand given in a register?

• Immediate Addressing

• Indirect Addressing

• Direct Addressing

• Register Addressing

What is the key feature of direct addressing mode in the 8051 microcontroller?

• The data is stored in the program memory.

• The address of the data is specified in the instruction.

• A register holds the address of the operand.

• The data is part of the instruction.

Which addressing mode uses the DPTR (Data Pointer Register) for accessing data?

• Indirect Addressing

• Indexed Addressing

• Direct Addressing

• Immediate Addressing