Re: A86: Sorry...
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Re: A86: Sorry...
They correctly emulate the TI-85. The hardware of the 85 and 86 are
identical, I believe (except for port 6 which controls the extra ram), so
the only differences would be rom call locations. On the 86, you have the
memory from $c000-$ffff that is for system use (stack, video ram, system
settings) and execution of asm programs. You also have $8000-$bfff (if ram
page 1 is swapped in, which it is during execution of an asm program) that
is used for the FPS stacks, but not during an asm program (unless the
program uses it).
So there's your 32k of ram, same as on the 85, same place as it on the 85.
Then the problem with rom calls comes into play. You can swap out the
memory from $4000-$7fff with another ram page and fake the 85 rom calls
there. Fortunately, most of the few rom calls were handled by the shell, so
you don't have to fake it with the rom. You can use the 32k of already free
ram for that just like the 85. For $0000-$3ffff, you're stuck, so you have
to patch the code.
I could be wrong about this, but it makes sense, and I've talked to Kirk
Meyer and I have the source code for an early version of YAS...
>Can someone tell me how YAS does its > 12k ZShell emulation? None of the
>programmers are giving me straight answers. :) Thanks.