lec 4

Question 1

what are the 2 types of interrupts you can use with a microcontroller

Answer 1

hardware and software interrupts

Question 2

how can you have a greater control when coding program

Answer 2

using both hardware and software interrupts can simply coding

Question 3

can parameters pass ISR when its called

Answer 3

No parameters can be passed

Question 4

what is ISR

Answer 4

Interrupt Service Routine

Question 5

where are the external inputs on arduino and on what pins

Answer 5

INT0 and INT1, on pins 2 and 3

Question 6

what function is required for the use of INT0 and INT1 and for what external inputs

Answer 6

attachInterrupt() function

pin 2 and 3

Question 7

what can ISR do

Answer 7

ISR can access global variables, however the variables need to be declared
as volatile if the ISR is required to change their values

Question 8

what 2 functions cant be used for ISR

Answer 8

Both delay() and millis() cannot be used in the ISR

Question 9

what 4 condition can happen when interrupt is triggered

Answer 9

LOW
CHANGE
RISING
FALLING

Question 10

what does timer interrupts allow you to do

Answer 10

execute tasks at very

precisely controlled timing intervals, regardless of the progress of code

Question 11

why is it very hard to accurately control timed events in 
void loop()

Answer 11

some commands have a longer execution time than others

Question 12

how to solve long execution commands on void loop()

Answer 12

Using a timer interrupt solves this problem

Question 13

how many timers does Arduino has

Answer 13

3 inbuilt timers