Arduino

This repo contains a bunch of programs that I created for the Arduino Uno board. This was entirely for educational purposes. All the programs are free software under the GPLv3, use them as you wish. You will need a few things in order to use these programs:

• an Arduino

• lib-avr

• avr-gcc

• avrdude

• a nice text editor

main.c

This is simple program that you can use to see the USART and the Timer1 in action.

adc.c

You can use this to see the ADC working on the board. Keep in mind that it converts the value into a character and spits it out using the USART. Thus, you will need something like GNU Screen to see it.

pwm.c

This program shows how PWM works on the arduino. It works best with an LED; you'll get a cool glowing effect. You can also use a servo with it but it'll act weird.

compile-convert-upload.sh

This is a shell script that you can run that will compile your code, convert it a intel .hex format, and upload it to the Arduino.

vu.c

This is a basic VU meter program. All it does is take the audio and output the volume to some LEDs right now. You can view the vu-amp.ps (you'll need to download it) file to see the op-amp circuit I designed in order for the Arduino to be able to pick up the voltage.

vu-amp.ps

This is a schematic for a simple op-amp circuit for the vu.c program. Please note that this is a generic design and the resistor values can be changed to whatever you want. In my case, I used a 25k pot for R2 so that I could keep the volume on the computer low and still get a good response on the LEDs. Also note that if you choose to use a pot, like I did, you want another resistor in series with it so that if you turn the pot all the way down, you don't short out the output of the op-amp.