Re: PC Transporter help!

[dempson@atlantis.actrix.gen.nz (David Empson)]

In article <3g625c$5f1@ionews.io.org>, Robert Tate <venom@bonk.io.org> wrote:
> Arrrrrrrrggggggggghhhhhhhhh!  Let's try again....
> 
> I'm looking for help with my PC Transporter card.  Actually, I want to 
> know what changes would be necessary for me to be able to run 286 based 
> programs on it and I also want to know if it would be able to perform 
> multitasking.

The PC Transporter uses an NEC V30 microprocessor, which has several
extra instructions (compared to an 8088 or 8086).  All of these
instructions were taken from the 80186 and 80286 instruction set.
Any software than requires an 80286 but runs in "real" mode (not
"protected" mode) should work on the PC Transporter.

Software requiring "protected" mode (sometimes called "16-bit" mode)
can not be used on a PC Transporter.  This rules out any software that
requires extended memory (beyond 1 megabyte), which is only accessible
in protected mode on an 80286 or later.  One feature you might see
mentioned with some programs is "DPMI" (DOS Protected Mode Interface).
This feature requires an 80286 or later processor running in protected
mode, so it won't work on the PC Transporter.

One program that comes to mind is 4DOS, a replacement for COMMAND.COM.
Earlier versions of 4DOS included 8088 and 80286 versions.  The 80286
version didn't offer any more features, but was faster and required
less memory.  It worked fine on the PC Transporter.

(With later versions of 4DOS, both the 8088 and 80286 versions are
incorporated into one COM file, and the appropriate instructions are
used; the PC Transporter still benefits from this.)

Most multitasking software for the 80286 will only run in protected
mode.  Some, such as Windows, can run in real mode, but with severe
limitations.  (The PC Transporter's video is another major limitation
when running Windows.)

In summary, you are limited to a very small subset of programs that
require an 80286.

You cannot replace the microprocessor on the PCT with an 80286.

> I am also interested in increasing the amount of RAM (currently 640k) to 
> a meg or more.

No can do.  The PC Transporter's design does not allow for any more
memory.  It actually has 768k of RAM, but the extra 128k is used for
video memory, buffering, and emulated hard drive and BIOS ROMs.


If you want a more powerful PC, buy a real PC.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand