On Wed, 27 Sep 2017, Liam Proven wrote:
... as usual, lots of high-quality info. Can't disagree with any of it.
thanks. many errors, due to inadequately refreshed dynamic wet-ware RAM
Chuck will probably notice most of them.
There were several additional programs, that were sometimes needed, such as
if you wanted to have a partition larger than 32MB on DOS 3.30 or earlier
(MS-DOS 3.31 was first to accept larger partitions).
Until this bit!
Vanilla PC-DOS and MS-DOS didn't get past 3.3, TTBOMK.
My turn to nit-pick.
There never was ANY version 3.3 !
And certainly no three point three!
You mean version 3 point THIRTY! (3.30)
Internally, starting with 2.00, the major version was stored as an
integer, and the minor version was a two digit decimal number.
INT21h Fn30h (place 30h in AH and INT21h) returned the major version in
AL, and the minor version in AH.
3.30 gave an AX of 1E03 ("three point thirty")
3.31 gave an AX of 1F03 ("three point thirty-one")
2.10 gave an AX of 0A02 ("two point ten")
2.11 gave an AX of 0B02 ("two point eleven")
"three point three" would be AX of 0303, and would be 3.03
A program to replicate the functionality of the VER command in a
program was an assignment that I used to give my Assembly Languuge
class.
In C, formatting would be
printf("$d.%02d",_AL,_AH);
to avoid 4.01 coming out as 4.1
My nitpick might only be important if you have 6.01 and 6.10, etc.
The first DOS I saw that could handle >32MB partitions was Compaq DOS
3.31 -- they tweaked it slightly.
How about ZENITH?
I thought that I had seen other 3.31s, but I never used them, so I'm not
sure.
Were the tweaks done BY Compaq, or by Compaq and Microsoft, in preparation
for support in later versions of DOS?
3.31 was only available as OEM versions of MS-DOS. There was no PC-DOS
3.31. Some OEMs had enhancements.
2.11 (0B02) was another version that was ONLY OEMs, often with some very
strange changes/enhancements, such as support for odd drives such as 3.5"
(not supported mainstream until 3.20 (1403)), MODE for switching between
internal/external video and 8 or 16 line internal displays (Gavilan 2.11),
etc.
BTW, Gavilan started (NCC 1983) with 3.0" drive, then single sided 3.5"
(SA300), and about the time that Gavilan destroyed itself (1985), they had
double sided 3.5" (SA350). Gavilan 3.5" double sided disk formats were
different from PC-DOS 3.5" formats until Gavilan 2.11K (unofficially
released after Gavilan was GONE.) In converting a Gavilan to 720K, to
get a clean look, transfer the bezel from a Gavilan SA300 to a stock SA350.
Gavilan was one of MANY early laptops, a full year later than Grid
Compass, but Gavilan appears likely to have been the first to use the term
"laptop".
PC-DOS 4.00 (0004) was "buggy". "The new DOS is so buggy that Norton
Utilities won't work!" How many of those "bugs" were simply CHANGES that
Norton fUtilities and the like were not prepared for?
PC-DOS 4.01 was supposedly "fixed" (think in a veterinary context?).
I had a copy of PC-DOS 4.01 that returned 0004! "ALL bugs fixed?"
Prior to 5.00 (0005), MS-DOS was "only for sale with a computer, or as
upgrade to such". In THEORY, it was not available for retail sale, but
there was a GIANT grey market, with no difficulty at all finding and
buying copies. There was NO apparent effort by Microsoft to rein in the
gray market.
5.00 was the first version with a RETAIL channel. It was ten years after
IBM and Microsoft signed - their contract obviously permitted Microsoft
selling to OEMs, but was there a clause in their contract that
forbade RETAIL sales [for ten years]?
BTW, "PC-DOS" was "descriptive" ("Personal Computer Disk Operating
System"), and was NOT a trademark. I personally confirmed that in the
stacks of the Patent nadTrademark Office in Virginia in 1987.
At least until after DRI brought "Concurrent PC-DOS" to market.
IBM was not amused.
http://online.wsj.com/public/resources/documents/googleglassuspto.pdf
"MS-DOS", however WAS trademarked.
SETVER (starting with 5.00) was even more fun.
Prior to that, one of the early assignments that I gave my Assembly
Language class was to modify EXE2BIN (our copy which came with PC-DOS
2.00 and the IBM release of MASM 1.0, was locked to DOS 2.00) to be DOS
version tolerant.
That employer only sold IBM and Compaq kit, and being that the UK was
poorer back then, mostly I only saw those and other cheaper clone PCs.
We didn't get to see some of the other States-side premium ranges, or
*I* didn't, until later, in the early-to-mid 1990s. So other vendors
may have had larger-disk-partition hacks, too. I recall reading of
some -- Wikipedia claims Commodore, Leading Edge, AST, NEC, AT&T,
Tandy, Sperry & Unisys all fiddled with FAT formats.
There was another, even more bizarre way to handle large drives, even
larger than 512MB!
In DOS 3.10 (0A03), they introduced the [undocumented?] "network
redirector". Remember MSCDEX?
3.10 had the 32MB limit. But, a CD-ROM was 2/3 GB (about 660MB). They
handled it with smoke and mirrors. If you tried to CHKDSK a CD-ROM
CHKDSK D:
It returned an error message:
"You can not CHDSK a network drive"!
I saw that used for large hard drives, but I don't remember ever seeing a
COMMERCIAL product to do it.
OB_Terminology:
IBM called the motherboard a "system board" or a "planar board", at least
partially due to repeated use of "mother_____" in a Black Panther speech
broadcast from Merritt College.
They thought that "HARD disk" would make it sound difficult to use, so
they called it a "FIXED disk" (think in a veterinary context)
--
Grumpy Ol' Fred ci...@xenosoft.com
"Blimey. Whoever your son's mate was who upgraded this PC for him, he
did an amazing job. I've never seen such an old PC tricked out as much
as this, and it's great workmanship."
I remain inordinately pleased by that, some 20y later...
praise well deserved.
