I am looking for a good ‘how to’ page on building a bootloader for a new processor.
The details of doing this are disorganized. So, here is a list of questions that I would like to have answered, and I am sure that it would be helpful to future viewers if it were all documented in one place. If a lot of people contribute to this I’ll be glad to put it all together in one document and post it back.
How to compile the boot loader from source code. Setting up the folders in the right place so that the compiler can find references to things such as avr/pgmspace.h and other includes. Which compiler to use? Can this be done with avr-gcc? How would that be done. I don’t understand makefiles, so how is this done from the command line?
How to modify the boards.txt file to get the sketches to download to the new device. What values to use for the fuse bits. Can I check them with AVR Dragon or other ISP programmer and use those values in boards.txt? What about 8mHz, 16Mhz and 20mHz micros? How do I get the baud rates right for each of these? What else needs to change to make it work at the new frequency?
When should I add a new build.core? Can’t everything be done with build.core=arduino? Why did Sanguino use a new core?
Things that I have missed because I have never done this before.
A complete resource. Does anything like this already exist for the Arduino IDE?