Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following is used as storage locations both in the ALU and the control section of a computer ?

A. accumulator
B. register
C. adder
D. decoder
Answer» C. adder
2.

The register which contains the data to be written into or read out of the addressed location is called

A. memory address register
B. memory data register
C. program counter
D. index register
Answer» C. program counter
3.

The register which holds the address of the location to or from which data are to be transferred is called

A. index register
B. instruction register
C. memory address register
D. memory data register
Answer» D. memory data register
4.

The stack pointer in the microprocessor is a

A. 16 bit register that point to stack
B. 32 bit accumulator
C. memory location in the stack
D. flag register used for the stack
Answer» B. 32 bit accumulator
5.

Which processor provided 1 MB memory:

A. 16-bit 8086 and 8088
B. 32-bit 8086 and 8088
C. 64-bit 8086 and 8088
D. 8-bit 8086 and 8088
Answer» B. 32-bit 8086 and 8088
6.

How many speed of 8088,8085,8086 microprocessor:

A. 2.5 million instruction per second
B. 1.5 million instruction per second
C. 3.5 million instruction per second
D. 1.6 million instruction per second
Answer» B. 1.5 million instruction per second
7.

Which is 16 Bit microprocessor:

A. 8088
B. 8086
C. 8085
D. all of these
Answer» E.
8.

ADC 0809 IS A ----- PIN IC

A. 40
B. 20
C. 24
D. 28
Answer» E.
9.

Conversion time of ADC 0808 IS

A. 100 ms
B. 100micro sec
C. 100 ms
D. 100ns
Answer» C. 100 ms
10.

Conversion time Tc of successive approximation ADC is given as

A. t(n-1)
B. t(n+1)
C. t(n)
D. t(n+2)
Answer» C. t(n)
11.

Whichof the following is the fastest ADC

A. dual slope
B. successive approximation
C. flash
D. single slope
Answer» D. single slope
12.

Upon activation of------ signal,output device reads data from output port and acknowledges it

A. intr
B. ack\
C. obf\
D. ibf
Answer» D. ibf
13.

To indicate end of conversion ADC 0808/0809 ACTIVATES -----SIGNAL

A. eoc
B. soc
C. clk
D. output control
Answer» B. soc
14.

Asynchronous serial communication involves transmission of

A. start bit
B. stop bit
C. character data
D. all
Answer» E.
15.

8255 sets INTR when STB'=-----,IBF=---------,INTE=--------,for input conrol signals

A. 1,0,1
B. 1,1,0
C. 1,1,1
D. 0,1,1
Answer» D. 0,1,1
16.

Walkie-talkie is an example of serial communication

A. simplex
B. half-duplex
C. full-duplex
D. none
Answer» C. full-duplex
17.

In ------ of 8255 ,bidirectionali/o data transfer is possible

A. mode0
B. mode1
C. mode2
D. bsr mode
Answer» D. bsr mode
18.

IBF is an active-------- output signal for 8255

A. high
B. low
C. enable
D. disable
Answer» B. low
19.

On activation of --------,8255 loads data from the input port lines into the input buffer of that port

A. stb\
B. ibf
C. obf\
D. none
Answer» C. obf\
20.

For i/o mode of 8255 ,if -----, the word is taken as a bit set/reset word

A. d7=1
B. d7=0
C. d0=1
D. d0=0
Answer» C. d0=1
21.

A high on ----pin causes all 24 lines of three 8 bit ports to be in the input mode

A. wr\
B. reset
C. gnd
D. vcc
Answer» C. gnd
22.

For i/o mode of 8255,if -----,the word is taken as a mode definition word

A. d7=1
B. d7=0
C. d0=1
D. d0=0
Answer» B. d7=0
23.

8255 has ----i/o modes

A. 2
B. 3
C. 4
D. 8
Answer» C. 4
24.

BSR mode is used to set or reset the bitsin

A. porta
B. portb
C. portc
D. portd
Answer» D. portd
25.

In 8255 ,BSR means -----

A. bit set/reset
B. byteset/reset
C. binary set/reset
D. none
Answer» B. byteset/reset
26.

8255 has three ----parallel ports

A. 8 bit
B. 16 bit
C. 32 bit
D. 64 bit
Answer» B. 16 bit
27.

8255 has -------- i/o pins

A. 28
B. 26
C. 24
D. 22
Answer» D. 22
28.

ADC 0808 operates on single ---- power supply

A. 5v
B. 10v
C. 15v
D. 20v
Answer» B. 10v
29.

EOC means

A. end of conversion
B. enable output conversion
C. error of conversion
D. none of these
Answer» B. enable output conversion
30.

ADC 0808 is ----- pin IC

A. 40
B. 20
C. 24
D. 28
Answer» E.
31.

for mode 3 of 8253/54, if the count is odd the output will be high for---

A. 2/(n+1)
B. (n+1)/2
C. 2/(n-1)
D. (n-1)/2
Answer» C. 2/(n-1)
32.

8253/54 has c----command that allows the user to check the count value programmed mode and current status of the counter

A. write back
B. write ahead
C. read ahead
D. read back
Answer» E.
33.

in mode 0 of 8253/54 ----disables counting

A. gate=1
B. gate=0
C. wr#=1
D. wr#=0
Answer» C. wr#=1
34.

8253/54 timers can be programmed in---modes

A. 1
B. 3
C. 6
D. 5
Answer» D. 5
35.

8253/54 has ----independent timers/counters

A. 1
B. 2
C. 3
D. 4
Answer» D. 4
36.

Flash ADC consist of….converters

A. 2^n
B. 2^n -1
C. 2^n +1
D. none of these
Answer» C. 2^n +1
37.

Adc 0808 uses ----technique

A. successive apraximation
B. single step
C. dual slope
D. flash converter
Answer» B. single step
38.

A high on ---line indicates that the buffer register is empty

A. txrdy
B. txe
C. txc#
D. both b and c
Answer» C. txc#
39.

to configure 8255 with port A output,Port B input port C lower output and port C upper input

A. mov al,0afh
B. mov al,0aeh
C. mov al,0ceh
D. mov a,0aah
Answer» C. mov al,0ceh
40.

the signals provided by ADC are

A. soc
B. eoc
C. ale
D. all of these
Answer» E.
41.

Asynchronous serial communication involves

A. start bit
B. stop bits
C. character data
D. all of these
Answer» E.
42.

Transmission through telephone lines is an example of….serial commuincation

A. simplex
B. half duplex
C. full duplex
D. none of these
Answer» D. none of these
43.

8255 has three ----parrallel port

A. 8bit
B. 16bit
C. 32bit
D. 64bit
Answer» B. 16bit
44.

on activation of ----, 8255 loads data from the input port lines into the input buffer of that port

A. stb#
B. ibf
C. obf#
D. none of these
Answer» C. obf#
45.

in ----, bidirectional data transfer is possible

A. mode 0
B. mode1
C. mode2
D. bsr
Answer» D. bsr
46.

walkie-talkie is an example of …..serial communication

A. simplex
B. half duplex
C. full duplex
D. none of these
Answer» C. full duplex
47.

for i/o of 8255,if -----, the word is taken as a bit set/rest word

A. d7=1
B. d7=0
C. d0=1
D. d0=0
Answer» C. d0=1