Author Archives: bengalvin

Beaglebot – A BeagleBoard based robot

Over the last 6 months or so I’ve been working on a BeagleBoard based robot. The motivation for this was to build a general robotics platform to try out some ideas I have on Simultaneous Localization and Mapping (SLAM) and robust sensor … Continue reading

Posted in BeagleBoard, Electronics, I2C, Linux, Microcontrollers, Uncategorized | Tagged , , , , , | 23 Comments

Changing the BeagleBoard I2C Bus Frequency

The stock kernel runs the I2C bus exposed on the BeagleBoard’s expansion header (bus 2) at 400KHz  (‘Fast’ mode). This is fine for most I2C slaves, however it seems to be too fast for slaves running on ATTiny and ATMega … Continue reading

Posted in BeagleBoard, I2C, Microcontrollers, Uncategorized | Tagged , , , | 1 Comment

Installing Ubuntu (Natty) on the BeagleBoard with RootStock

There are prebuilt Ubuntu images suitable for the BeagleBoard, however if you want more control over what’s included in your filesystem, and your kernel, RootStock is a good option. RootStock will assemble a complete Ubuntu file system, a kernel image and … Continue reading

Posted in BeagleBoard, Linux | Tagged , , | 8 Comments

Hot-Air Soldering QFN packages

QFN (Quad Flat No leads) packages are the devil’s work. As the name implies there are no leads, just tiny pads on the bottom of the chip where it’s almost impossible to get a soldering iron or test probe to.  … Continue reading

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Switched Mode Power Supply for the BeagleBoard

I had a couple of options to consider when creating a power supply for my BeagleBoard based robot: a simple linear voltage regulator (eg the LM7805) or a fancy switched mode power supply. Normally I’d go straight for the linear … Continue reading

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Interfacing the BeagleBoard with an ATtiny85 Microcontroller over I2C

The next part of my project involves connecting a dozen or so sensors and actuators to the BeagleBoard, ideally in a modular, extensible way. The obvious way to do this is use some  microcontrollers, and interface them with the BeagleBoard … Continue reading

Posted in BeagleBoard, Electronics, I2C, Microcontrollers | Tagged , , , , , | 4 Comments

Programming an ATtiny85 Microcontroller with the AVRISP mkII

The ATtiny85 is an 8 pin microcontroller, complete with 8KB of flash, and 512 bytes of EEPROM and SRAM. It also has some hardware support for I2C (otherwise known as TWI), which makes it ideal for my current project. Here … Continue reading

Posted in Electronics, Microcontrollers | Tagged , , , | 4 Comments