Found a very interesting Russian site discussing Dreamshell - a
homebrew OS for the Dreamcast.
They have some very nice hardware pages, including schematics for:
- Dreamcast Serial to SD card adaptor - easily available online
- Dreamcast Serial to Ethernet adaptor - under testing
attached hardware, but people are reporting 650KBytes/sec write speed
(out of a theoretical 1.5Mbytes/sec, which isn't bad for a $20 shipped
to your door adaptor). Oh, and have ordered one :)
Also, while the Dreamcast is typically quoted as having 16MB of RAM, it also has 2MB of "audio RAM" (attached to the ARM sound controller), and another 8MB of video RAM. If you're running a 3D game on the Dreamcast this division of memory may make a lot of sense, but when running a general purpose OS much of that 10MB could be put to better use. Even if its too slow (or simply unavailable) to run programs in directly (more research needed), it should at least be possible to make it available for swap space or even a ram disk.
So, I think there is real scope for some NetBSD/dreamcast related kernel hacking during the rest of RetroChallenge 2012. It will make a change from just plugging together existing stuff in unusual ways, or writing vintage fantasy computer simulators.