On 1/3/02 at 6:25 PM Peter Graf wrote: >Hi Nasta,
>>> I'm sorry, but I must destroy any hopes that Coldfire CPU's >>> (version > 1) could execute our existing QL software. >>I would very much appreciate if you could give us some more >>details on this. >Two examples for CF V4e: > >- mov.b xxx,-(sp)' adjusts the stack pointer by -1 >- lsl and lsr set the overflow bit to the same as the carry bit > >Both can not be forced to trap out. What a stupidity. >No way code on the CF core can solve this in general. >(Except emulating the whole 68k CPU, of course.) What stupidity, indeed! I recall the first example being a bug in early 68000 silicon... looks like someone used the old source code! The second is just utterly stupid, there is no reason to do anything with the overflow bit doing LOGICAL shifts (not arithmetic). This has to be a bug. Now I'm glad I didn't go redesigning anything for the V4 coldfire... Even so, the fact remains that we have run out of 68k CPUs for the time being. We can whine about not having 68070 etc, or we can change the software that keeps being incompatible. It doesn't take much to figure out which one is the more doable. Nasta
