muazsalah / beaglebone_atmega

Getting the BeagleBone to talk to an AVR ATmega MCU using the I2C interface

BeagleBone I2C ATmega

Table of contents

1. What is this?
2. Contents
3. Supported devices
4. References

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1. What is this?

A combination between an I2C master (a beagle bone) and an I2C slave (an AVR ATmega328 MCU). The I2C master is written in Python while the slave is in C and is compiled using WinAVR.

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2. Contents

There is two folders with the following contents:

BeagleBone

• Adafruit_I2C.py
• LEDs_Blink.py
• LEDs_OFF.py
• LEDs_ON.py

ATmega

• main.c
• I2C_slave.c
• I2C_slave.h
• Makefile

Adafruit_I2C.py

The I2C library written by Adafruit, this is driver code for the I2C interface

LEDs_Blink.py

This code will blink the LEDS on the slave ATmega328 PB0 and PB1

LEDs_OFF.py

This code will turn OFF the LEDS on the slave ATmega328 PB0 and PB1

LEDs_ON.py

This code will turn ON the LEDS on the slave ATmega328 PB0 and PB1

main.c

This is a piece of example code which reads and writes on the I2C interface and is a proof of concept only

I2C_slave.c

This file contains all the function declarations to setup and work with the TWI hardware peripheral inside the AVR. It takes care of the interrupt handling and receiving the bytes.

Make sure you add this source file to your Makefile!

I2C_slave.h

This file contains the function prototypes

This file has to be included in your source file

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3. Supported devices

Though I have only tested this library on an ATmega328P it should be running on all major ATmega AVRs which has built-in I2C

Additionally, the I2C master code ||should|| work on Beagle Board and Raspberry Pi, after changing the bus address (in BeagleBone it is 3, in R-Pi it is 0)

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4. References

BeagleBone

http://beagleboard.org/Products/BeagleBone

Installing Ubuntu (Raring 13.04) on the BeagleBone

http://elinux.org/BeagleBoardUbuntu#Raring_13.04_armhf

Enabling SSH Server on Ubuntu (OpenSSH)

https://help.ubuntu.com/12.04/serverguide/openssh-server.html

I2C Tutorial on the BeagleBone

http://www.gigamegablog.com/2012/11/04/beaglebone-coding-101-i2c/

My write-down of this test project

http://eshortcircuit.blogspot.ae/2013/06/atmega-has-got-new-friend-beaglebone.html