Past Meetup

Arduino Class - Taking a closer look at the Atmega microcontroller - part 1


Location image of event venue


Come join us at Education Center in Plano TX to learn more about the Atmega microcontroller used in the Arduino Uno platform. In this class we will be covering the following:

Hardware interrupts Part 1: Introduction ( (12:16) In this first demo, we'll take the circuit from the button class and only modify the sketch it so that the LED is lit as a response to an interrupt generated by the button, instead of by polling the state of the button a few million times per second.

Hardware interrupts Part 2: Using volatile variables ( (5:17) In the second demo, we'll add a volatile variable which the code in the interrupt request function will be able to access and update. This variable will keep track of the number of times that we have pressed on the button.

Hardware interrupts Part 3: Timers ( (5:08) In this demo, we'll make an LED blink by setting a timer to trigger an interrupt once every second.

Hardware interrupts Part 4: High-definition Pulse Width Modulation ( (6:09) The TimerOne library also contains several other useful functions that you can explore. One of them provides that ability to create very accurate PWM output. In this fourth demo, I'll show you how to use the TimerOne library to create a PWM pulse.

Using the built-in pull-up resistors ( (7:16) In this lecture, you will learn how to use the Atmega's internal pull-up resistor on it's output pins. This is a convenience feature that will save you from having to use external pull-up resistors. Parts Needed:

Arduino UNO ( An LED ( Mini push button. ( A 10KΩ Resistor ( 330 resistors ( Course work for this class comes from Arduino Step By Step ( which has over 20 hours of content in 110 lectures. These classes are designed for anyone interested in learning electronic design and C programming. No experience is required. Access to the course material is free at our meetups. If you wish to access the material outside the meetup see our coupons page to get a discount from our sponsor (