On Wed, Apr 07, 1999 at 04:10:53PM +0100, Si Owen wrote: > Ian Collier wrote: > > Does the Amstrad DSK format not cover this? (I don't actually > > know anything about it, except that it is more complicated than > > a straight dump of all the tracks on the disk.)
> I've not found any official docs for it but I've flicked through the > comments in some ASM code that reads them, and it does seem to cover things > like unformatted tracks, but I didn't see anything for non-512 byte sectors. I think there is an official doc - probably somewhere on Kev Thacker's Amstrad site. > I was wondering whether the your current core would benefit from having the > register pairs in little endian order so HL can be accessed without shifting > and ORing the two 8-bit parts, so I might give that a try at some time - it > can conditionally be compiled as big endian for the platforms that need it. I'm not sure what you are getting at here. The endianness shouldn't make any difference since memory is not involved directly (though I guess the x86 will have to use memory because it doesn't have enough registers). If you force it to go to memory then it could make the emulator slower on other architectures (this was the main problem with xzx on the sparc). It was basically a choice between keeping 8-bit quantities and shifting+ORing whenever register pairs are used, and keeping 16-bit quantities and shifting whenever single registers are used. I made the choice arbitrarily as it seemed easier to deal with the 8-bit registers individually. imc
