i'd like to use an OS for the ARM7 project i have. this is a real time application and it involves USB, SD card, serial comm and i may need to use the Ethernet. can you recommend on OS that should simplify the development and won't burden on the project's budget?
Keil's RTX could be useful.
Yes, Keil RTX would be useful, also because RealTime Library supports USB, File System and Ethernet, and all are already prepared for RTX.
Clearly, if you ask this question in the Keil site, you are going to get a preference for Keil answers!
For a wider view, try: www.arm.com/.../index.html