You have to use the #pragma SRC at the top of the C source file to get the compiler to convert files with inline assembly to a .SRC file (or other name if you use the form #pragma SRC(filename.ext) ). You then also need to include this resulting source file into the project list for the project.

My experience with inline assembler is that it is a pain to use it effectively!!! What I would recomment instead is to make a separate A51 assembler source file where you put your time critical code and then call it as a subroutine from C. It also works a whole lot better this way in the debugger. I have found this to be particularly true in the Cygnal IDE where Keil tools are integrated to the IDE. All this works a bit better in the Keil native IDE but I have found that the Keil inline assembler support to be cumbersome as compared to the inline ASM on say a DOS platform with Borland BC3.1

Michael Karas