8051 Microcontroller set 3

Que: 21 To initialise any port as an output port what value is to be given to it?
a. 0xFF
b. 0x00
c. 0x01
d. A port is by default an output port
Que: 22 Which out of the four ports of 8051 needs a pull-up resistor for using it is as an input or an output port?
a. PORT 0
b. PORT 1
c. PORT 2
d. PORT 3
Que: 23 Which of the ports act as the 16 bit address lines for transferring data through it?
a. PORT 0 and PORT 1
b. PORT 1 and PORT 2
c. PORT 0 and PORT 2
d. PORT 1 and PORT 3
Que: 24 Which of the following registers are not bit addressable?
c. A
d. PSW
Que: 25 Which instruction is used to check the status of a single bit?
a. MOV A,P0
b. ADD A,#05H
c. JNB PO.0, label
d. CLR P0.05H
Que: 26 Which addressing mode is used in pushing or popping any element on or from the stack?
a. immediate
b. direct
c. indirect
d. register
Que: 27 Which operator is the most important while assigning any instruction as register indirect instruction?
a. $
b. #
c. @
d. &
Que: 28 What is the advantage of register indirect addressing mode?
a. it makes use of registers R0 and R1
b. it uses the data dynamically
c. it makes use of operator @
d. it is easy
Que: 29 Which of the following comes under indexed addressing mode?
c. MOV A,R0
d. MOV @R0,A
Que: 30 Is this a valid statement ?SETB A
a. yes
b. no
c. cant be determined
d. none of the mentioned