Lecture 3 - Timers

Question 1

What is the bit-width of Timer 0 and Timer 2?

Answer 1

8-bits

Question 2

What is the bit-width of Timer 1?

Answer 2

16-bits

Question 3

What register stores the current counter value for Timer 1?

Answer 3

TCNT1

Question 4

True or False: The 10-bit prescaler can be applied on both the internal and external clock signal for Timer 1?

Answer 4

False. The prescaler only applies to the internal clock source.

Question 5

What register is used to enable Timer 1 interrupts?

Answer 5

TIMSK

Question 6

How often will Timer 1 overflow if it uses the default internal clock of 1MHz and a prescaler factor of 1024

Answer 6

1us x 1024 x 2^16 = 67 seconds

Question 7

What register is used to select the type of events that will trigger a Timer 1 input capture interrupt?

Answer 7

TCCR1B

Question 8

What register stores automatically the timer value when a Timer 1 input capture interrupt occurs?

Answer 8

ICR1

Question 9

On what IO port can we find the input capture pin of Timer 1?

Answer 9

Port D (D.6)

Question 10

How many timers does the ATmega16 have?

Answer 10

3

Timer 0, Timer 1, Timer 2

Question 11

At what speed is the internal clock set at in the ATmega16?

Answer 11

1MHz

Question 12

Which timer can use both internal and external clock source?

Answer 12

Timer 1

Question 13

How often will Timer 1 overflow?

Answer 13

Will overflow every 2^16us, since it is a 16-bit counter