8085 Microprocessor MCQ

111. Which one of the following 8085 assembly language instructions does not affect the contents of the accumulator?

1. CMA
2. CMP B
3. DAA
4. ADD B

112. If the accumulator of an Intel 8085A microprocessor contains 37 H and the previous operation has set the carry flag, the instruction ACI 56 H will result in

1. 8E H
2. 94H
3. 7E H
4. 84 H

113. Examine the following instruction to be executed by a 8085 microprocessor. The input port has an address of 01 h and has a data 05 h to input:

IN 01 H

ANI 80 H

After the execution of the two instructions the following flag portions may occur:

1. Zero flag is set
2. Zero flag is reset
3. Carry flag is cleared
4. Auxiliary carry flag is set

Select the correct answer using the codes given below:

1. 1 and 3
2. 2, 3 and 4
3. 1, 3 and 4
4. 1, 2 and 4

114. For 8085 microprocessor, the instruction RST 6 restarts subroutine at address

1. 00 H
2. 03 H
3. 30 H
4. 33 H

115. Which one of the following function is performed by the 8085 instruction MOV H, C?

1. Moves the contents of H register to C register
2. Moves the contents of C register to H register
3. Moves the contents of C register to HL pair
4. Moves the contents of HL pair to C register

116. Consider the execution of the following instructions by an 8085 microprocessor:

LXI H, 01FF H
SHLD 2050H

After execution, the contents of memory locations 2050H and 2051 H and the registers H and L, will be

1. 2050 H→ FF; 2051 H→ 01 ; H→ FF; L→ 01
2. 2050 H→ 01; 2051 H→ FF ; H→ FF; L→ 01
3. 2050 H→ FF; 2051 H→ 01 ; H→ 01; L→ FF
4. 2050 H→ FF; 2051 H→ 01 ; H→ 00; L→ 00

117. In 8085 microprocessor, a number of the form 000XXXX0 stored in the accumulator is processed by the programme (Assume CY = 0) as follows

ANI FF H

RAL

MOV B, A

ANI FF H

RAL

ANI FF H

RAL

ADD B

The operation carried out by the programme is

1. multiplication of accumulator content by 10
2. complement of accumulator content
3. multiplication of accumulator content by 9
4. rotation of accumulator content three times

118. When RET instruction is executed by any Subroutine then

1. the top of the stack will be popped out and assigned to the PC
2. without any operation, the calling program would resume from instruction immediately following the call instruction
3. the PC will be incremented after the execution of the instruction
4. without any operation, the calling program would resume from instruction immediately following the call instruction, and also the PC will be incremented after the execution of the instruction

119. An 8085 microprocessor-based system uses a 4 K x 8-bit RAM whose starting address is AA00 H. The address of the last byte in this RAM is

1. 0FFF H
2. 1000 H
3. B9FF H
4. BA00 H

120. The address bus of Intel 8085 is 16-bit wide and hence the memory which can be accessed by this address bus is

1. 2 k bytes
2. 4 k  bytes
3. 16 k bytes
4. 64 k bytes