Hi James.
>> I can't remember if I mentioned, but I bought a
>> Hand 386 computer to try to test PDOS/386 on real
>> hardware. It died before I could do much of anything.
> Yes, I saw (with interest as I have some similar goals to you) you
> mention you had bought a PC clone. When you say it died do you mean the
> boot failed or that the machine itself is now dead?
In recent times I bought 2 modern Hand 386 and then a
vintage 386SX.
The first 2 machines (both Hand 386) are physically dead.
They still have power though.
> If the latter, do you think it was some step of your program that it
> couldn't cope with?
No. I doubt that simple INT 13H can physically kill
a machine. And regardless, it did actually do some
of those INT 13H before it died. I did multiple test
runs fixing things.
Also someone else ran the same code (ie my latest
test) on their Hand 386, and the machine didn't die
(PDOS got further and hung though - which surprised me,
because I thought my code was good, and was working
under emulation). I have added some debug and asked
that person to run another test, and it has been
waiting a few days now as he is busy.
>> In the meantime I purchased an old 386SX, since the
>> new Hand 386 was no longer available for sale.
> OK. Genuine 386-based PCs were very expensive last time I looked.
It cost something like US$400 on ebay.
Expensive compared to what? Certainly not Sydney
real estate prices. Fun fact: Sydney is not the
capital of Australia.
>> That's all I really wanted to know - that PDOS/386
>> has no non-80386 instructions in it. Instead of hoping
>> the emulators are perfectly correct
> That's a bit confusing. You tested your code on a 386SX to check it had
> no 386 instructions in it?
I said non-386, not 386.
> Surely you would want to test on a real 8086/8088.
PDOS/386 won't work on an 8086. That's why it has
"386" in the name, as opposed to PDOS/86 which I
have already tested on a real NEC V20 in my Book 8088
(I have 2 of those too, both working).
> FWIW my CPU detection code does theoretically distinguish between 8086,
> 80186 and 80286 but I've never had a real 186 to test it on. Instead, I
> found two emulators, only one of which apparently behaved correctly as a
> 186.
I am thinking that I should have a single PDOS
distribution that does that detection and
automatically loads PDOS/86, PDOS/286 (not yet
written), PDOS/386 or PDOS/x64 and sets the PATH
to the appropriate set of executables.
So it will run on anything, transparently. You will
only notice the difference if you try to edit a
large file as that will be determined by available
memory.
z/PDOS is also meant to look identical, eventually.
Normally you wouldn't even be able to tell that it
is EBCDIC.
BFN. Paul.