Microcontroller Questions and Answers Part-16

1. Which of the following is true about the FRFQx bits of the BTCTL register?
a) these bits are used for clock input
b) these bits are used for setting a particular frequency fLCD
c) these bits start the timer
d) these bits stop the timer

Answer: b
Explanation: FRFQx bits of the BTCTL register are used for selecting a particular frequency fLCD varying from fACLK/256 to fACLK/32.

2.Timer1 is responsible for ________
a) providing a clock to the LCD module
b) cause an interrupt
c) a pulse for the RTC
d) all of the mentioned

Answer: d
Explanation: Timer1 is responsible for providing a clock for the LCD module. It can also cause an interrupt if the BTIE bit is high. It also provides the clock to the RTC.

3. For fACLK = 32 KHz, what would be the desirable range of fLCD?
a) 2hz-256hz
b) 12hz-512hz
c) 128hz-1khz
d) 1khz-10khz

Answer: c
Explanation: For fACLK = 32khz, the desirable range of the fLCD is the fACLK/256 to fACLK/32. This value comes out to be in the range of 128hz-1khz.

4.Normally BTCNT1 only function is to provide a prescalar for the BNTCNT2?
a) true
b) false
c) cant be said
d) depends on the conditions

Answer: a
Explanation: LCD’s controllers nowadays don’t require a clock pulse, so the only main function of the BTCNT1 is to provide a prescalar for the BNTCNT2

5. BTCNT2 provides 2 output signals?
a) true
b) false
c) cant be said
d) depends on the conditions

Answer: b
Explanation: BNTCNT2 has no outputs. Instead, it raises the BTIFG flag at a frequency determined by the BTIPx bits.

6. RTCSEC, RTCMIN, RTCDOW etc. are the bytes of a set of registers that are used to store
a) seconds
b) minutes
c) days of a week
d) all of the mentioned

Answer: d
Explanation: The current time and date are held in a set of registers that contain the following bytes like RTCSEC, RTCMIN, RTCHOUR, RTCDOW etc.

7. The RTC module is configured in the calendar mode if __________
a) RTCMODE bit is reset
b) RTCMODE is set
c) RTCRDY is reset
d) RTCRDY is set

Answer: b
Explanation: Calendar mode is selected when RTCMODE is set.

8.The RTC module makes use of the Basic Timer1 because of _________
a) its bytes are controlled in the Basic Timer1 register
b) it is started by timer1
c) it is ended by basic timer1
d) it needs a clock pulse of 1hz that is provided by basic timer1

Answer: d
Explanation: The RTC module requires a clock of worth 1hz that is provided by basic timer1 so that why it makes use of basic timer1.

9. IF RTCIE interrupt is generated then _________
a) BTIFG flag is set
b) RTCFG flag is set
c) Both flags are set
d) None of the flag is set

Answer: c
Explanation: When RTCIE interrupt is generated then both BTIFG and RTCFG flags are set simultaneously.

10. What does the RTCTEVx bits do?
a) they cause an interrupt
b) they end an interrupt
c) they set the minute, hour, seconds daily at midnight or daily at noon
d) all of the mentioned

Answer: c
Explanation: Every minute, every hour, daily at midnight or daily at noon are set by the bits of the RTCTEVx bits of the RTCCTL register.