Electronics and Electrical Engineering 2

Mechanical Engineering MCQ Question Papers: DRDO, ISRO, Interview

Subject: Electronics and Electrical Engineering 2

Part 2: List for questions and answers of Electronics and Electrical Engineering

Q1. 8051 series of micro controllers are made by which of the following companies?
a) Atmel
b) Philips
c) None of the mentioned
d) Both of the mentioned

Q2. AT89C2051 has RAM of
a) 128 bytes
b) 256 bytes
c) 64 bytes
d) 512 bytes

Q3. 8051 series has how many 16 bit registers?
a) 2
b) 3
c) 1
d) 0

Q4. When 8051 wakes up then 0x00 is loaded to which register?
a) DPTR
b) SP
c) PC
d) PSW

Q5. When the micro controller executes some arithmetic operations, then the flag bits of which register are affected?
a) PSW
b) SP
c) DPTR
d) PC

Q6. On power up, the 8051 uses which RAM locations for register R0- R7
a) 00-2F
b) 00-07
c) 00-7F
d) 00-0F

Q7. How many bytes of bit addressable memory is present in 8051 based micro controllers?
a) 8 bytes
b) 32 bytes
c) 16 bytes
d) 128 bytes

Q8. When the call instruction is executed the top most element of stack comes out to be
a) The address where stack pointer starts
b) The address next to the call instruction
c) Address of the call instruction
d) Next address of the stack pointer

Q9. LCALL instruction takes
a) 2 bytes
b) 4 bytes
c) 3 bytes
d) 1 byte

Q10. Are PUSH and POP instructions are a type of CALL instructions?
a) Yes
b) No
c) None of the mentioned
d) Can’t be determined

Q11. What is the time taken by one machine cycle if crystal frequency is 20MHz?
a) 1.085 micro seconds
b) 0.60 micro seconds
c) 0.75 micro seconds
d) 1 micro seconds

Q12. What is the counting rate of a machine cycle in correlation to the oscillator frequency for timers?
a) 1 / 10
b) 1 / 12
c) 1 / 15
d) 1 / 20

Q13. Which special function register play a vital role in the timer/counter mode selection process by allocating the bits in it?
a) TMOD
b) TCON
c) SCON
d) PCON

Q14. How many machine cycle/s is / are executed by the counters in 8051 in order to detect ‘1’ to ‘0’ transition at the external pin?
a) One
b) Two
c) Four
d) Eight

Q15. Which bit must be set in TCON register in order to start the ‘Timer 0’ while operating in ‘Mode 0’?
a) TR0
b) TF0
c) IT0
d) IE0

Q16. Who controls the timer1 especially when it is configured as a timer in mode’0′,where gate and TR1 bits are attributed to be ‘1” in TMOD register ?
a) TR1
b) External input at (INT1)
c) TF1
d) All of the above

Q17. Which timer mode exhibit the necessity to generate the interrupt by setting EA bit in IE enhancing the program counter to jump to another vector location ?
a) Mode 0
b) Mode 1
c) Mode 2
d) Mode 3

Q18. A galvanometer in series with a high resistance is called ……
a) An ammeter
b) A voltmeter
c) A wattmeter
d) None of the above

Q19. An ammeter should have ………….. resistance
a) Infinite
b) Very large
c) Very low
d) None of the above

Q20. A voltmeter is connected in a ………….. With the circuit component across which potential difference is to be measured
a) Parallel
b) Series
c) Series or parallel
d) None of the above

Part 2: List for questions and answers of Electronics and Electrical Engineering