How can I use a project specific preprocessor/precompiler or any other tool before running the buildin C166 compiler?
uVision processes file groups in order, and files within groups in order. Therefore you'd need to ensure that your custom preprocessing was done in an early group in the Project. You'd have to use the "custom translator" feature. An unfortunate side-effect of that is that you lose all dependency handling. So it might be just as easy to do it all in a simple Batch file! See http://www.keil.com/forum/docs/thread4513.asp