How many pins of the 8255 can be used as the I/O ports?

What will be the final value of the code? MOV A ,#53H MOV R0, 58H ADD A,R0 DA A

Which of the following is not a Special Function Register (SFR)?

Which addressing mode is it ?

Which pin in the 8051 microcontroller is used to enable/ disable the external memory interfacing ?

Which of the following registers in the 8051 microcontroller is an 8-bit register?

SCON register in the 8051 microcontroller is having the values 10001100. then the mode of microcontroller's serial communication is :

How much time delay will be generated by NOP instruction in 8051, assuming a crystal frequency of 12 MHz ?

Which addressing mode is used to push data onto the stack in the 8051 microcontroller?

After the execution of the following 8051 assembly code, what will be the contents of the stack addresses 0AH and 09H?

MOV R0, #22H

MOV A, #77H

SETB PSW.3

MOV R0, #64H

PUSH 0

PUSH 8

PUSH 0E0H

(Assume default stack area and register bank 0)