I want to know the commands, functions in C which can be done in AT91RM200 microcontroller
have a glance of compiler manual first....
http://www.keil.com/support/man/docs/uv3/
That's not the compiler manual
This is the CARM compiler manual: http://www.keil.com/support/man/docs/ca/
The RealView manual still doesn't seem to be online... :-(