Re: LZ: Lots 'o questions...
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Re: LZ: Lots 'o questions...
On Sat, 27 Jul 1996, Peter Cordes wrote:
> Joshua Lynch wrote:
> >
> > I'm fairly new to z-80/zshell/ti-85 assembler programming (i just
> > learned this morning :))
> > and i had a few questions:
> >
> > 1. where can i find the list-zshell FAQ? i tried kuai but it seems as though
> > its gone. :(
> Try ticalc.org
>
> > 2. I know the difference between ROM & RAM but what are the differences in
> > accessing them?
> accessing the ROM is done with ROM_CALL( or call (see the ti-85.h file
> for more info on this) and RAM is accessed by ld a,value \ ld
> $memorylocation,a
>
> > 3. What portions of RAM can i use to store variables and such and are there
> > specially
> > allocated portions of RAM that i should not overwrite?
> See the file TI-RAM.TXT
>
> > 4. is there an assembler to use on the TI-85 itself so I don't have to use a
> > computer?
> Look for the file compiler.zip on ticalc.org(i think that is the file
> name) but the maximum size of the program will be a little more than
> 1000 characters because compiler uses a LIST varible
The compiler only converts handwritten machine langauge in to executable
Zshell code.
>
> > 5. what are pages of memory? and what pupose do they serve?
> don't know that one.
The Z80 microprocessor can only access so much memory at a time, so
paging is used to view diffrent bits of memory in a "window". A port is
accessed to change which window to look through. (the same thing is used
in the OLD ems memory used on XTs). I think the max memory the Z80 can
handle is 64k.
>
> > 6. what is the difference between video memory and regular (if there such a
> > thing) memory
> video memory is the memory used by the video card in the TI-85 and i
> guess would be the memroy that is normally accessed when you use the
> TI-OS but when programming the programmer would normally use text memory
> and registers for storing information.
Pretty much. The Video Memory section of memory is mapped to the video
controller and used to draw to the screen.
>
> Peter Cordes of Maximus Productions
> Visit Maximus Productions home page at: http://www.ntsource.com/~pcomp
>
References: