Nikon IR Remote
I've been wanting to do this project for quite some time but have been waiting for the cooler weather, that's when I do most of my projects. This was one of the first projects on my list because I want to use what I learned here in another more ambitious project that I'll be starting shortly. The picture below shows the finished product and as you can see there are very few parts and a very simple layout. I'm a software guy if I can do it anyone can. The total price of materials for this project was right around $11 and it took maybe 1-1/2 to do everything with the only thing remainingis to find some kind of enclosure for it, but it works and that is not a show stopper.
SPI Master and USI Slave communications
Serial Peripheral Interface or SPI might be referred to as a non-standard standard as there doesn't seem to be any official specification on the subject. The best reference I've found are in the Atmel datasheets and "AVR319: Using the USI module for SPI communication". The older Atmel chips did not use the SPI protocol they instead had a Universal Serial Interface or USI that was close to SPI and with a little effort can be used to communicate with a device using the SPI protocol.