Page 1 of 1

What software works with Jr?

PostPosted: Fri Jun 01, 2018 5:22 am
by OldComputerGuy
Are there any comprehensive lists of what software works with the Jr and what software doesn't?

Re: What software works with Jr?

PostPosted: Fri Jun 01, 2018 7:00 am
by Brutman
It's kind of an impossible question to answer. Let's look at it a different way.

For software to run on a PCjr it should:
  • Use BIOS calls to set the screen modes (but direct writes to the CGA buffer are fine)
  • Not require more than 112KB of memory unless you can boot DOS with a memory device driver
  • Not assume what the keyboard layout is. (Again, use the BIOS.)
  • Use the BIOS for floppy disk or hard disk writes.

Those are the areas of major concern: screen mode setting, the memory map, the keyboard, and the disk drive.

In 1983 this was a major problem. By 1985 or so there were many other machines that were not 100% IBM PC 5150 register level compatible, and people stopped doing a lot of the bad things they were doing that was breaking the PCjr because those same things were breaking laptops and other clones.


Mike

Re: What software works with Jr?

PostPosted: Fri Jun 01, 2018 10:01 am
by OldComputerGuy
So the PCJr ad that showed all the stacks of software that work with Jr has never actually been verified, then. :(

Re: What software works with Jr?

PostPosted: Fri Jun 01, 2018 10:11 am
by Brutman
I'm not sure you can draw that conclusion. I just pointed out a different way to look at the problem.

For me, most DOS software just works. If you have enough memory and it lets you install to a hard drive then it's probably well written enough to run on a PCjr. If it's going to tweak very specific hardware registers, then it might be problematic.