Is there any Editor or Compiler to C language for Windows CE 3.1 (Jornada 720 - HPC 2000), because I'm a Visual Basic developer and I have bought a book of C only for play with this language in my free time, and the time that is free to me I'm using my Jornada 720, but remember that I've want something like PocketC or only a compiler but free, and remember to, that I've want it to be onboard, not in to compile in my computer.
These links might be useful to you:
Free C++ (and C) Programming Tools
Introduction to Development Tools for Windows Mobile-based Devices
eMbedded Visual C++ might be an appropriate tool for you in Windows. I've used it in the past to develop on a Windows CE device.