8051 viva

Which of the following statements is false?

• All 8051 ports are bi-directional

• All 8051 ports are bit-programmable

• All 8051 ports output FFH after reset

• All 8051 ports need external pull-ups

The size of on-chip program memory for 8051 is

• 4K bytes

• 8K bytes

• 16K bytes

• 64K bytes

What should be the values of RS1 and RS0 bits of PSW SFR to select register bank #2?

• 1 and 0, respectively

• 1 and 1

• 0 and 0

• 0 and 1,respectively

What is the reset value of the SP?

• 00H

• 70H

• FFH

• None of these

What would be done by the following instruction, when executed?

MOV A, 0F0H

• Load A by F0H

• Copy from F0H in R2 of bank #1

• Copy register B to register A

• None of these

How many bits of the jumping address are available in AJMP instruction?

• 11 bits

• 10 bits

• 9 bits

• 8 bits

What would the processor do after executing the instruction SJMP 0FEH?

• Execute from 0FEH

• Execute the same instruction again

• Execute from 0002H

• None of these

Assuming accumulator contains 80H and the Carry flag is cleared, which of the following instructions, when executed, would set the Carry flag and clear the accumulator?

• RRC A

• RLC A

• RL A

• RR A

If a JB instruction is placed at the address 0200H and the addressed bit is not set, from which address the next instruction would be executed?

• 0200H

• 0201H

• 0202H

• 0203H

After execution of MUL AB instruction, the higher byte of the product would be available in

• The accumulator

• B register

• PSW

• SP