Okay, that fits my experience. What I'm getting with JS is it boots okay, and I can type and press enter. Most commands work. Attempting to write or run any SuperBASIC causes a freeze. Accesses to mdv#_ cause a freeze.
With Minerva, I can enter a SuperBASIC program and run it, but any of the rest above causes a freeze. My board uses a 16-bit wide image in flash, which is a LOT faster than the 8-bit one. The video RAM is still 8-bit though, which is the main bottleneck. This is purely for compatibility with the old QL custom logic. Next, I'd like to implement the standard QL expansion port on it. It's pretty neat. It's nearer GC than SGC speed right now but I'm working on that. On Sat, Mar 16, 2013 at 3:26 PM, Thierry Godefroy <[email protected]> wrote: > On Sat, 16 Mar 2013 11:16:42 -0500, Dave Park wrote: > > > Hi all, > > > > It's been mentioned that vanilla QDOS/Minerva doesn't run happily on > > 68EC020 due to CPU differences. The GC/SGC copies and patches the OS to > > work with the EC020 CPU, and to relocate certain resources. > > > > My questions are: what are the differences? > > For all 680x0 CPUs above the 68000/8 (ie. for 68010/012/020/030/040/060s), > the MOVE from SR instruction is priviledged while it is not for the > 68000/8. This is the usual cause of incompatibilities for software > written for the 68000 and ran on a newer processors. > > You therefore have to patch those pieces of software to invoke the MOVE > from SR instruction only from supervisor mode. > > There's also the VBR but it should be initialized to 0 on reset, so > this should not cause an incompatibility. With the VBR, however, you > can move the exception vectors (which are normally held in ROM, at > address 0 ownwards) to RAM (in the SGC example, this is probably what > happens: it might change the VBR to point to the start of the patched > QDOS/Minerva copy in RAM, with modified vectors pointing to the patched > exception handlers). > > Thierry. > _______________________________________________ > QL-Users Mailing List > http://www.q-v-d.demon.co.uk/smsqe.htm > -- Dave Park Sandy Electronics, LLC [email protected] _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
