In article <452184A6.10705@black-star.demon.co.uk> you write:
>RPC_WSCONS from 4-BETA does work correctly. That gives something to diff 
>against. I'll carry on digging.

I've done some digging myself, and I found one problem -- I'd broken the
initialisation of the IOMD FSIZE register.  I've fixed that now
(vidc20config.c rev 1.29), and that seems to have at least fixed 
640x480x8 on my machine.  Can you try a new kernel and see if there's 
anything else broken that you think shouldn't be?

-- 
Ben Harris                                                   <bjh21@NetBSD.org>
Portmaster, NetBSD/acorn26               <http://www.NetBSD.org/Ports/acorn26/>