Learn to write ATtiny board definitions/bootloaders

Hi,
Recently I have been doing a lot of work with ATtiny boards. While there are a number of board definitions that cover the majority of ATtiny boards for programming use with Ardiuno not all are covered. I have seen the great work done with ATtiny core Google Code Archive - Long-term storage for Google Code Project Hosting.

I was wondering if anyone knew how to write the board definitions/bootloaders and could point me in the direction of a tutorial/guide.

Thanks for your help!

not all are covered.

Not all support bootloaders, and some are not possible to support at all (ie they're not supported by gcc, or have very small memories.)

It would be better to ask questions about a specific target CPU.

There is a bootloader tutorial at AVRFreaks.net, but that's not a good place to ask about the arduino-specific parts.

What are your suggestions if we were to focus on the ATtiny84?

It would be better to ask questions about a specific target CPU.

Ben1234:
What are your suggestions if we were to focus on the ATtiny84?

The Tiny Core supports the ATtiny84 family (t84, t44, t24) of processors.