Re: Q: Launching DOS 3.3 from ProDOS?

[rubywand@aol.com]

In article <1996Nov8.152057.1@wsuhub.uc.twsu.edu>,
mselliot@wsuhub.uc.twsu.edu writes:

>
>I once heard of a ProDOS program called DOS 3.3 launcher,
>or something like that- that would allow you to run most DOS 3.3
>programs from ProDOS. Does anyone know if this program exists,
>and if it is on a FTP site somewhere?


     John MacLean's DOS 3.3 Launcher 2.0 should be available on one of the
following:

ftp://ground.isca.uiowa.edu/2/apple2/upload/AOL/
ftp://apple2.caltech.edu/zocalo/pub/apple2/

     The package includes the Launcher, a copier, some other items, and an
infromative READ.ME file. Evidently, it lets you Copy and convert DOS 3.3
programs into a form which the Launcher can launch under ProDOS. For
example, you can launch from the GS/OS Finder, ProSel, etc.. It includes
an option to set the speed (on a IIgs) at which a program will be run. A
IIgs or 128k IIe or IIc is required.


     Of course, quite a few DOS 3.3 programs can be copied to a ProDOS
diskette and run with no need for any changes at all. Others will run okay
if just a few incompatible commands are changed and/or file names are
changed along with references to the files in the program. For instance,
TITLE PIC would need to become TITLE.PIC and, in the program,

 100 PRINT CHR$(4)"BLOAD TITLE PIC"

would be changed to

 100 PRINT CHR$(4)"BLOAD TITLE.PIC"


     Some DOS 3.3 wares will not run under standard ProDOS because they
try to load data into an area ProDOS protects. For example, a program may
want to BLOAD a lo-res pic into the Text Page area. Jeff Blakeney
discussed fixes for this problem in the Spring '96 issue of II Alive.

     It turns out that you can do a POKE 48984, 192 in, say, your STARTUP
program, to deprotect the Text Page and, then, run many otherwise
un-runnable DOS 3.3 programs under ProDOS. (As noted in the article, use
of this quickie fix is recommended only for diskettes which boot ProDOS
and need to run the "un-runnable" wares. You would not use this approach
when launching wares from hard disk or on a diskette which also launches
ProDOS programs like Appleworks.)   

     There are some DOS 3.3 programs which, short of major modifications,
simply will not run under ProDOS. Programs which are very large may not
fit in the reduced space allowed by ProDOS. Programs which CALL DOS
3.3-specific routines and compiled BASIC programs are other poor
prospects. 
     



   


Rubywand