intro to RISCOS Development

Hi

I’m interested in helping to develop / port riscos

could anybody give me any pointers to set me in the right direction with tool chains etc?

also i had a look at the source repos and i’m unsure which is the correct one

thanks

Simon

Hi Simon,

Depending upon which bits of RISC OS you want to work on, you’ll need to have strong C programming skills. For lower level stuff, including porting to new hardware, strong (and recent) ARM coding skills will be essential. There are a few peripheral bits of RISC OS that use C++ but these are few and far between.

For the toolchain, you mainly require the Desktop Development Environment (DDE) from the ROOL store – we’d like to migrate one day to building RISC OS with free tools (like GCC and co) but that’s probably not going to be possible for some time. The DDE is native to RISC OS so you’ll either need RISC OS hardware or an emulator.

Next, you should familiarise yourself with the CVS version control system, as this has historically been what the RISC OS source code is stored in. See our CVS repository.

For instructions on how to do builds of RISC OS and similar, you could do worse than starting with the pages in our wiki here – mainly those first two links. Once you’ve got the DDE, you can download a source code tarball for a given build (e.g. OMAP3Dev) from here rather than accessing CVS directly, and try doing a build by following those wiki page instructions.

Finally, once you’ve got your head around all of that, you can look at some of the porting-related documentation, and more detailed technical notes, such as documentation for the RISC OS Hardware Abstraction Layer

Something that could be better described in the documentation if I could work out where to put it, is how to checkout a source tree for whatever platform you want to build.

First, check out castle/Admin/bin/ from the CVS repository
That gives you a script called ‘castle/Admin/bin/checkout’
Then poke around in the Products folder to find the name of the platform you want (eg OMAP3 for BeagleBoard stable, OMAP3Dev for development, BCM2835Dev for Raspberry Pi)
Then run ‘checkout platform_name’

I find this much easier to deal with than using tarballs. The checkout perl script will run on RISC OS and other platforms.