Re: Apple2 Software Question

[Rubywand <rubywand@swbell.net>]

Nathan Mates writes ...
> 
> In article <35268AE6.CC0A8EEB@iserv.net>,
> Lisa Wildfong  <newdream@iserv.net> wrote:
> >I have some old apple2 software. Dos 3.3,games and some productivity
> >software. I'd like to know what will these run on. Some of the disks say
> >they need Applesoft and 48K Mem.
> >I know there are apple2's,2GS,2e,2plus,2c's and probably more. I just
> >want to know will this software run on all or just some.
> 
>    Unless it is copy protected or relies on undocumented and
> unsupported ROM entry points used, the Apple //e, //c, GS, and IIc+
> will run the above pieces of software ....


     Unfortunately, the above guarantee overlooks a few potential
problems. For starters, at the time many DOS 3.3 wares were created, it
was standard practice to regard any entry point which remained stable
over the Apple II "System Monitor" (1977) and Apple II+ "Monitor II"
(1978 Autostart) ROMs as, practically speaking, "supported".

     Apple merely lists a small number of "Useful Monitor Subroutines"
in the Apple II Reference. Programmers commonly used many more entry
points than just the few mentioned. Some of these entry points changed
in later models.

     A few DOS 3.3 games will not boot under the GS Slot 6 disk
controller. 

     Another source of compatibility problems is the decision to
maintain some important IIc status bytes in Text/Lo-res 'Page' 1
"holes". A number of DOS 3.3 programs BLOAD pic screens and/or Text
directly into this area with the result that, for example, Text CR's and
LF's may fail to be handled properly rendering game directions, prompts,
etc. unreadable.

     A few games do dual-'page' hi-res animations in a way the GS fails
to handle correctly. For example, an explosion effect may be smeared
across the display instead of being erased.

     A few Dos 3.3 programs may feature double-hires displays. These
will not run correctly on a II, II+, or unenhanced IIe.

     A few DOS 3.3 wares may require upper/lower case keyboard inputs
and/or display of upper/lower case characters. These will not run
correctly on a standard, unmodified II or II+.


     Of course, we do not know which particular DOS 3.3 games and
productivity products may be in Lisa's collection. They may all run fine
on all Apple II's. On the other hand, it does not seem like a good idea
to issue a blanket guarantee.



Rubywand