RO5.x IOMD
Posted: Fri Aug 16, 2013 6:10 pm
As RO5 potentially has Application space overlapping VIDC1 / IOC / Screen memory when at the Supervisor level, we need to unmap it before any translation will work.
I can implement a *ADFUnmapLegacyMemory command which can simply unmap memory pages from the relevant areas. The potential problem however is BASIC, it's going to expect the memory to be there unless its memory ends at &1000000. We need to somehow limit memory to 16MB when the WIMP isn't running.
The alternative is to stay within the WIMP when booting floppies, which we've discussed previously. The issue here is that it may well break quite a lot of games. What I could do is switch Boot Floppy to boot within the WIMP and only drop to the Supervisor is the SHIFT key is held down. I'll add to 2.18 and we'll have to test games to see what breaks.
I can implement a *ADFUnmapLegacyMemory command which can simply unmap memory pages from the relevant areas. The potential problem however is BASIC, it's going to expect the memory to be there unless its memory ends at &1000000. We need to somehow limit memory to 16MB when the WIMP isn't running.
The alternative is to stay within the WIMP when booting floppies, which we've discussed previously. The issue here is that it may well break quite a lot of games. What I could do is switch Boot Floppy to boot within the WIMP and only drop to the Supervisor is the SHIFT key is held down. I'll add to 2.18 and we'll have to test games to see what breaks.