I want to write some real time code, and if possible, on a hard real time system. This is a home project and a commercial RTOS is out of the question. I am thinking of assembling a PC-104 stack and some version of Linux, but am open to options. The target will run the real time code only. I would like to develop on my Windows 7 system and download to the real time computer. If necessary I will allocate a computer to the real time development system and run some version of Linux on it. (I would rather have two computers than mess with dual boot.)
I have no CPU preference. I want to concentrate on writing the software rather than developing the support system. I have a simple game in mind (a hardware device, not user interaction on a CRT), and want to do some work with accelerometers and gyroscopes.
What hardware and software combination do you recommend?