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 |
(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?
|
| a. SCON |
| b. PCON |
| 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 |
(b). it uses the data dynamically
Que: 29 Which of the following comes under indexed addressing mode?
|
| a. MOVX A, @DPTR |
| b. MOVC @A+DPTR,A |
| 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 |