Ok, yet another link to another site, but screw it, I’m bored so here it is!
Here’s another resource that should be useful to anyone getting to grips with the black art of AVR USART comms. The guys at extremeelectonics have published a very comprehensive tutorial on the various registers related to the AVR USART peripherial, how to set them, etc.
Having recently starting to teach myself AVR microcontroller development without the comfort zone offered by the Arduino, one problem that really gets on my nerves as an absolute beginner is trying to calculate the UBRR (USART Baud Rate Register) value for a given baud rate and crystal/resonator speed when using the USART communications functionality of the AVR.
Enter WormFood’s AVR Baud Rate Calculator. This site has been mentioned on blogs before, but it’s so useful that I’d be mad not to mention it here as well!
I finally got my Bus Pirate from Seeed Studio today ( I was one of the Pre-order 2 lot.) Unfortunately though, there was a bit of a problem with mine. No firmware was loaded on it at the factory!!?? It seems like one of those things you make sure is on your to-do list with devices like this but the problem is easilly solved.
Anyway, after emailing Seeed, they pointed me in the direction of this forum thread which explains the problem. There is also a blog post at dangerousprototypes.com which explains how to obtain the firmware and upload it onto the Bus Pirate. A word of warning: You will need a jumper handy to complete the process. Just salvage one off of an old Hard Drive or something, that’s what I did.
Hope this is useful to others who may be having the same problems. I should hopefully (money and time permitting) be doing some fun stuff with this little device over the coming months so stay tuned.