FW: How to add new target device (MCU)?

[Ian Lance Taylor]

MathEE <math_ee@yahoo.com.tw> writes:

> I'm trying to find out a way to add a new target MCU (say, T123) such that I can compile C and/or Assembly into instruction set of this T123.
> Then, just like "-mmcu=attiny24", I can use "-mmcu=T123" to get the Hex/Bin for T123.
>
> Or shortly, how to support a new target device?
>
> Of course, I have all information needed about this T123.
> But I have no idea what/how to do?
> Could somebody please be so kind to help/teach me??

Look at the files in gcc/config/avr.  Specifically, avr-mcus.def and
avr-devices.c.

Ian