26 Oct
2005
26 Oct
'05
6:44 p.m.
I've been going through some old files and discovered a few of documents
that I can't decide if they belong in the the shredder or with someone who
gives a darn about them.
Does anyone remember the background behind the "Explorer 88 PC" by
Netronics R&D circa 1983? Was it a do-it-yourself PC kit? Anyway, I've
got the schematics for the thing.
I've also got the guide by Purple Computing for their Purple -2 Kit on how
to put 256K on your PC motherboard by cutting and changing a few jumpers
and then adding a board that attaches over the memory array that holds 64K
DRAMS. I'd forgotten that the original PC was limitied to 64K on the mobo.
Time erodes one's memory.
I've also got the manual for the Teletype 410640 printer logic card
assembly. IIRC, this was for the Model 40 line printer. It includes
schematics and parts layout.
...and I discovered a complete unopened OEM kit for MP/M II, complete with
licensing pricelist and 8" floppies. I'd forgotten all about it. (I may
hang on to this one for the time being).
Funny thing is that I don't remember half the stuff in my files...
Cheers,
Chuck
26 Oct
26 Oct
7:07 p.m.
On 26/10/05 23:44, "Chuck Guzis" <cclist at sydex.com> wrote:
I've also got the guide by Purple Computing for
their Purple -2 Kit on how
to put 256K on your PC motherboard by cutting and changing a few jumpers
and then adding a board that attaches over the memory array that holds 64K
DRAMS. I'd forgotten that the original PC was limitied to 64K on the mobo.
I'd have thought this was worth saving if it's related to the 5150 XT, or at
least it is to me. I'm trying and failing miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
Cheers
a
4:27 p.m.
At 12:07 AM 10/27/05 +0100, you wrote:
On 26/10/05 23:44, "Chuck Guzis" <cclist at sydex.com> wrote:
I may be wrong but I thought IBM was already using 256k MBs before they
introduced the XT.
Joe
I've also got the guide by Purple Computing
for their Purple -2 Kit on how
to put 256K on your PC motherboard by cutting and changing a few jumpers
and then adding a board that attaches over the memory array that holds 64K
DRAMS. I'd forgotten that the original PC was limitied to 64K on the mobo.
I'd have thought this was worth saving if it's related to the 5150 XT, or at
least it is to me. I'm trying and failing miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to. 
7:15 p.m.
Adrian Graham wrote:
On 26/10/05 23:44, "Chuck Guzis" <cclist
at sydex.com> wrote:
Would there be any way to reliably estmate the percentage of XT's that
were upgraded with Sixpack (or similar) cards?
Peace... Sridhar
I've also got the guide by Purple Computing
for their Purple -2 Kit on how
to put 256K on your PC motherboard by cutting and changing a few jumpers
and then adding a board that attaches over the memory array that holds 64K
DRAMS. I'd forgotten that the original PC was limitied to 64K on the mobo.
I'd have thought this was worth saving if it's related to the 5150 XT, or at
least it is to me. I'm trying and failing miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
7:29 p.m.
On 27/10/05 00:15, "Sridhar Ayengar" <ploopster at gmail.com> wrote:
Would there be any way to reliably estmate the
percentage of XT's that
were upgraded with Sixpack (or similar) cards?
From my point of view, no, but I'm a Digital fan
through and through and so
avoided IBM's stuff back then :) A similar question
for us UK types would be
to ask how many Acorn BBCs were modified by schools/colleges/whatever. Given
the current pile of them under my stairs I'd guess the figure was about 80%!
Cheers
a
8:17 p.m.
On 10/27/2005 at 12:29 AM Adrian Graham wrote:
I was no IBM PC fan even when it came out. Initially, I'd looked at
upgrading my S-100 system with one of Bill Godbout's 8086 boards and some
memory--it would have been cheaper than the PC route back then. But Jade
didn't have any of the cards in stock and was a bit iffy about delivery
times, so I went down to Computerland and bought a PC.
Around then, Sears (from their computer store) was ostensibly selling PCs,
but while they had a demo system with CGA, they didn't have any units for
sale.
For a time, even IBM PCs were hard to come by.
Cheers,
Chuck
From my point
of view, no, but I'm a Digital fan through and through and
so
avoided IBM's stuff back then :)
27 Oct
27 Oct
3:23 a.m.
On 27/10/05 01:17, "Chuck Guzis" <cclist at sydex.com> wrote:
Around then, Sears (from their computer store) was
ostensibly selling PCs,
but while they had a demo system with CGA, they didn't have any units for
sale.
For a time, even IBM PCs were hard to come by.
Just like now in fact, though I guess I'm not actively looking for one -
just waiting for it to drop into my lap. Figuratively speaking :)
A
3:27 a.m.
On 10/27/05, Adrian Graham <witchy at binarydinosaurs.co.uk> wrote:
On 27/10/05 01:17, "Chuck Guzis" <cclist at sydex.com> wrote:
Good thing for the "figuratively speaking" else it'll bound to break
your femur. :-)
Around then, Sears (from their computer store)
was ostensibly selling PCs,
but while they had a demo system with CGA, they didn't have any units for
sale.
For a time, even IBM PCs were hard to come by.
Just like now in fact, though I guess I'm not actively looking for one -
just waiting for it to drop into my lap. Figuratively speaking :)
12:44 a.m.
Adrian Graham wrote:
A similar question for us UK types would be to ask how
many Acorn
BBCs were modified by schools/colleges/whatever. Given the current
pile of them under my stairs I'd guess the figure was about 80%!
*modified* - or just having stuff done to them that was as Acorn
intended? They were supposed to be a highly customisable machine from
the outset - it's rare I see one that's had anything really odd done to
it. Most of the ones I've seen from schools were pretty stock, just with
various frills (commercial RAM / ROM expansion boards, disk upgrades,
Econet boards fitted etc.)
Of course how often have I seen one that's never had the lid taken off
since it left the factory in order to have something done to it (even if
it's just to add another ROM)? Probably never. :)
cheers
Jules
30 Oct
30 Oct
3:51 p.m.
...
A similar question for us UK types would be to ask how
many Acorn
BBCs were modified by schools/colleges/whatever. Given the current
pile of them under my stairs I'd guess the figure
was about 80%!
...
Out museum has a fairly nice collection of networking technologies that
didn't make the cut when Ethernet Switching won the war. One thing we don?t
have is a sample of Econet. If anybody has a sample "under the stairs" that
they would consider parting with I would be happy to pay the postage to get
it here.
We don't sing because we're happy - We're happy because we sing!
mailto:gilcarrick at comcast.net?
web page: http://goodtimeschorus.org/
Gil Carrick
VP Chapter Development/ Ex-Webmaster
1012 Portofino Dr., Arlington, TX, 76012
817-274-2210
31 Oct
31 Oct
8:28 a.m.
Gil Carrick wrote:
Out museum has a fairly nice collection of networking
technologies that
didn't make the cut when Ethernet Switching won the war. One thing we don?t
have is a sample of Econet. If anybody has a sample "under the stairs" that
they would consider parting with I would be happy to pay the postage to get
it here.
Not right now, but I likely will have some spares (clock box, Econet
modules for BBC micros etc.) at some point within the next year. I want
to set up an Econet at Bletchley once things are more stable there,
hence the reason I don't know what I'll have spare yet.
I expect I could find you a couple of BBC micros if needs be too,
although postage costs probably start going through the roof at that point!
You might want to keep an eye out for other Econet-related bits in the
meantime - Acorn Econet bridge, SJ Research Econet bridge, PC Econet
card, Atom Econet card, Acorn Master Turbo (so you can run a fileserver)
etc. as none of those are very common. Clock boxes and Econet modules
for the BBC B / Master tend to turn up quite often in comparison.
cheers
Jules
26 Oct
26 Oct
7:36 p.m.
Sridhar Ayengar wrote:
I would be interested in seeing a list of the variations of the PC (with
/ without tape interface) and the XT
as well as the AT. the things I'm interested in is memory config (which
type chips) number of ISA slots,
and the on board varations such as having or omitting the tape interface
present on the original PC. (those
sort of variants).
I may have a motherboard in the heap somewhere with 5 slots, and 64K but
I don't recall seeing an
8 slot (XT) board with only 64 k. I have seen two variants of memory
types on both the XT and AT,
as far as the chips. The AT of course had the silly stacked memory
chips, initially.
jim
I'd have thought this was worth saving if it's related to the 5150
XT, or at
least it is to me. I'm trying and failing miserably to find an XT
with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
Would there be any way to reliably estmate the percentage of XT's that
were upgraded with Sixpack (or similar) cards?
Peace... Sridhar
4:34 p.m.
At 04:36 PM 10/26/05 -0700, you wrote:
Sridhar Ayengar wrote:
I would be interested in seeing a list of the variations of the PC (with
/ without tape interface) and the XT
as well as the AT. the things I'm interested in is memory config (which
type chips) number of ISA slots,
and the on board varations such as having or omitting the tape interface
present on the original PC. (those
sort of variants).
Get a copy of Upgrading and Repairing PCs by Mueller. It has all those
details plus things like BIOS versions and dates, part numbers for all the
cards, details on the various power supplies, etc. It's still in
publication but I doubt the new editions still have all the details for the
PC, XTs and ATs. I found a first edition in a surplus store last week and
it gives loads of details about the early PCs. Check the used book stores,
libraries, E-bay, etc and you should be able to find an early edition
without too much trouble.
Joe
I'd have thought this was worth saving if it's related to the 5150
XT, or at
least it is to me. I'm trying and failing miserably to find an XT
with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
Would there be any way to reliably estmate the percentage of XT's that
were upgraded with Sixpack (or similar) cards?
Peace... Sridhar
I may have a motherboard in the heap somewhere with 5 slots, and 64K but
I don't recall seeing an
8 slot (XT) board with only 64 k. I have seen two variants of memory
types on both the XT and AT,
as far as the chips. The AT of course had the silly stacked memory
chips, initially.
jim
10:08 p.m.
jim stephens wrote:
/ without tape interface) and the XT
This reminds me: I have a music program that claimed to send multi-voice sound
through either the PC speaker or the cassette interface. While I know how it
did this feat through the PC speaker (tied the speaker to a timer port and
pulsed), I have no idea how the cassette interface stuff worked. Other than
BIOS calls, is there any documentation out there (port addresses, etc.) on the
cassette interface? I have a 5150 right here I'd love to dork around with.
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Want to help an ambitious games project? http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
27 Oct
27 Oct
3:26 p.m.
This reminds me: I have a music program that claimed to send multi-voice sound
through either the PC speaker or the cassette interface. While I know how it
did this feat through the PC speaker (tied the speaker to a timer port and
pulsed), I have no idea how the cassette interface stuff worked. Other than
BIOS calls, is there any documentation out there (port addresses, etc.) on the
cassette interface? I have a 5150 right here I'd love to dork around with.
Of course therre's docuemntation. IBM sold a proper TechRef for this
machine with schematics and BIOS source.
Cassette output (which is what you're interested in) uses channel 2 of
the 8253 counter/timer -- the same channel that's used for speaker
output. The output of the 8253 is buffered by U63a ('38), then fed to a
potential divider to set the right audio level (aux or mic levels are set
by a jumper on the mainboard, it simply selects taps on this potential
divider)
Casssette input is doen almost all in software. The incoming signal is
amplified/clipped by U1 (741 op-amp), then fed to port PC4 on the
mainboard 8255.
The motor control relay is driven my port PB3 of this 8255, suitably
buffered. Note that if the relay is not energised, then the aux-level
output is fed back to the cassette input circuit via the relay contacts
to be used for self-test diagnositcs.
-tony
29 Oct
29 Oct
10:41 p.m.
Tony Duell wrote:
Of course therre's docuemntation. IBM sold a
proper TechRef for this
machine with schematics and BIOS source.
I know that -- I don't own a copy and can't seem to find one on ebay or
otherwise (I do look for these things before I ask questions, you know :-)
Thanks for the info.
--
Jim Leonard (trixter at oldskool.org)
World's largest electronic gaming project: http://www.MobyGames.com/
A delicious slice of the demoscene: http://www.MindCandyDVD.com/
Various oldskool PC rants and ramblings: http://www.oldskool.org/
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.362 / Virus Database: 267.12.5/150 - Release Date: 10/27/2005
30 Oct
30 Oct
5:13 p.m.
Tony Duell wrote:
AH, OK. A suprising number of people don't realise that the PC techrefs
exist, or how complete they are.
I had the good sense (!) to buy an almost complete of the PC-familiy ones
(that is, not the PS/3 stuff) when they were just still available from
IBM.
They sure are hard to find elsewhere, though.
-tony
Of course therre's docuemntation. IBM sold a
proper TechRef for this
machine with schematics and BIOS source.
I know that -- I don't own a copy and can't seem to find one on ebay or
otherwise (I do look for these things before I ask questions, you know :-) 
6:03 p.m.
On Sun, 30 Oct 2005 22:13:28 +0000 (GMT)
ard at p850ug1.demon.co.uk (Tony Duell) wrote:
I've had the good sense to snap them up where I've been able to get them.
And I have the IBM PC/XT/AT volumes, and also the TechRef for the Compaq Deskpro 386
(which is just as comprehensive as the IBM references, and IMPORTANT because it gives
insight into newer tech that the IBM-AT). And god no, I didn't pay IBM or
Compaq's prices for them.
I also have most of the IBM Techrefs scanned in PDFs.
Tony Duell wrote:
AH, OK. A suprising number of people don't realise that the PC techrefs
exist, or how complete they are.
I had the good sense (!) to buy an almost complete of the PC-familiy ones
(that is, not the PS/3 stuff) when they were just still available from
IBM.
They sure are hard to find elsewhere, though.
Of course therre's docuemntation. IBM sold a
proper TechRef for this
machine with schematics and BIOS source.
I know that -- I don't own a copy and can't seem to find one on ebay or
otherwise (I do look for these things before I ask questions, you know :-) -tony
--
http://sasteven.multics.org/MacSE30/MacSE30.html
10:25 p.m.
Scott Stevens wrote:
I also have most of the IBM Techrefs scanned in PDFs.
Are these available online somewhere? I have several 5150s that are in various
stages of working order that I'd like to repair, and one 5150 in perfect
working order that I like to program low-level stuff on...
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Want to help an ambitious games project? http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
10:23 p.m.
Tony Duell wrote:
They sure are hard to find elsewhere, though.
Which is why I'm grateful you're on this list :-)
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Want to help an ambitious games project? http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
31 Oct
31 Oct
6:59 p.m.
Tony Duell wrote:
The PC TechRefs are nowhere near the most obscure or rare manuals I have.
I mean, does anyone else have the techncial manuals for the P851 and P854
by their bed :-)
On the other hand, few people need the P851 microcode sources. Rather
more seem to be interested in the IBM PC.
-tony
They sure are hard to find elsewhere, though.
Which is why I'm grateful you're on this list :-)
26 Oct
26 Oct
7:34 p.m.
On 10/27/2005 at 12:07 AM Adrian Graham wrote:
I'd have thought this was worth saving if it's
related to the 5150 XT, or
at
least it is to me. I'm trying and failing miserably to find an XT with a
64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
Mine was for the PC, not the XT; but even with 256K on the mobo, it wasn't
the memory that made me ditch the thing. It was the FIVE EXPANSION SLOTS!
Consider that you had one slot for CGA, one for printer, one for a serial
port, one for FDC--and if you needed more memory, that was it. I had a
homebrew board that hooked to an SA-1000/WD-1001 hard disk combo and I'd
reached the limit--and the power supply was getting stressed to the point
that you might have to power on and off several times before you got it to
quit kicking out.
So, the next time the Taiwanese contingent held a show, I bought a clone
MOBO and nice 8-slot flip-top case and a whopping 150w power supply. Duped
the PC's ROMs into the clone's EPROMs and could even run IBM BASICA. I
never looked back.
Cheers,
Chuck
8:52 p.m.
Mine was for the PC, not the XT; but even with 256K on
the mobo, it wasn't
the memory that made me ditch the thing. It was the FIVE EXPANSION SLOTS!
And what is wrong with the 5161 expansion cabinet? That would add a total
of 6 more slots to the system (there are 8 slots in the expansion
cabinet, one is taken up by the receiver board, and you lose one in the
main system for the driver board).
-tony
5:06 p.m.
At 01:52 AM 10/27/05 +0100, you wrote:
Well besides being HUGE and the fact that it didn't support all of the
cards, it costs $2585! (with a hard drive) That's almost three times what
I paid for my first XT clone! FWIW I've only seen one of the things. They
must not have sold many of them.
Joe
That would add a total
Mine was for
the PC, not the XT; but even with 256K on the mobo, it wasn't
the memory that made me ditch the thing. It was the FIVE EXPANSION SLOTS!
And what is wrong with the 5161 expansion cabinet? of 6 more slots to the system (there are 8 slots in the
expansion
cabinet, one is taken up by the receiver board, and you lose one in the
main system for the driver board).
-tony
9:26 p.m.
Joe R. wrote:
At 01:52 AM 10/27/05 +0100, you wrote:
Well besides being HUGE and the fact that it didn't support all of the
cards, it costs $2585! (with a hard drive) That's almost three times what
I paid for my first XT clone! FWIW I've only seen one of the things. They
must not have sold many of them.
At that price, it's no wonder!
I've seen two or three at various IBM manufacturing sites.
Peace... Sridhar
Mine was
for the PC, not the XT; but even with 256K on the mobo, it wasn't
the memory that made me ditch the thing. It was the FIVE EXPANSION SLOTS!
And what is wrong with the 5161 expansion cabinet?
9:42 p.m.
On 10/26/2005 at 9:06 PM Joe R. wrote:
Well besides being HUGE and the fact that it
didn't support all of the
cards, it costs $2585! (with a hard drive) That's almost three times what
I paid for my first XT clone! FWIW I've only seen one of the things.
They
must not have sold many of them.
I used one for a time. 62 conductor thick round cable connected the two.
I recently scrapped the PC-side board of one--lots of LS374's IIRC. I
recall that IBM swore that the added delay was negligible, but I kept
running into the of "You're not running our card in the expansion unit, are
you? " problem. The cable wasn't long enough that you could do much else
than stack the two units on a normal sized desktop. And then, the
resulting pile was too high to set a monitor on. Two PSU fans didn't make
for a quiet workplace either.
I remember buying a Taiwanese mobo, case and a Sony monitor to replace the
PC 2-box setup at one of the De Anza college swap meets. The monitor cost
more than the PC. I think I tried using the expansion unit with the 8 Mhz
clone and had no luck at all.
Cheers,
Chuck
9:50 p.m.
I actually have one of these. My wife's uncle worked at IBM and bought the
PC and the expansion unit "way back when". It was a PC case with a backplane
and the interface card, connected by a 3' shielded cable which IMHO was way
too stiff for normal use. This unit has a 20mb hard drive in it and the last
time I used it (3-4 years ago) it worked fine.
If $2850 was the original price, that's a rip off. It's an empty PC case, a
backplane, power supply and an ISA card. $400 in parts at the most.
-----Original Message-----
From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]
On Behalf Of Chuck Guzis
Sent: Wednesday, October 26, 2005 9:42 PM
To: cctalk at classiccmp.org
Subject: Re: PC Ephemera
On 10/26/2005 at 9:06 PM Joe R. wrote:
Well besides being HUGE and the fact that it
didn't support all of
the cards, it costs $2585! (with a hard drive) That's almost three times
what
I paid for my first XT clone! FWIW I've only seen
one of the things.
They
must not have sold many of them.
I used one for a time. 62 conductor thick round cable connected the two. I
recently scrapped the PC-side board of one--lots of LS374's IIRC. I recall
that IBM swore that the added delay was negligible, but I kept running into
the of "You're not running our card in the expansion unit, are you? "
problem. The cable wasn't long enough that you could do much else than
stack the two units on a normal sized desktop. And then, the resulting pile
was too high to set a monitor on. Two PSU fans didn't make for a quiet
workplace either.
I remember buying a Taiwanese mobo, case and a Sony monitor to replace the
PC 2-box setup at one of the De Anza college swap meets. The monitor cost
more than the PC. I think I tried using the expansion unit with the 8 Mhz
clone and had no luck at all.
Cheers,
Chuck
27 Oct
27 Oct
3:13 p.m.
At 01:52 AM 10/27/05 +0100, you wrote:
Well besides being HUGE and the fact that it didn't support all of the
It is, of course, the same size as the PC or XT system cabinet, and can
stack on top of it.
Mine was
for the PC, not the XT; but even with 256K on the mobo, it wasn't
the memory that made me ditch the thing. It was the FIVE EXPANSION SLOTS!
And what is wrong with the 5161 expansion cabinet? cards, it costs $2585! (with a hard drive) That's
almost three times what
From what I remmember, you can't put video cards in
the expansion
cabinet, and if you want to put memory in it, you have to set DIP
switches on one of the expansion unit cards to set the address boundary
between memory in the system unit and memory in the expansion cabinet
(that implies, of course, that memory from 0 to some address is in the
system unit, memory above that address is in the expansion cabinet). I am
not aware of any problems with any pure I/O port cards going in the
expansion cabinent.
I paid for my first XT clone! FWIW I've only
seen one of the things. They
must not have sold many of them.
They are fairly rare, but I hae at least 2, and maybe 3.
-tony
26 Oct
26 Oct
8:50 p.m.
On Thu, 27 Oct 2005, Adrian Graham wrote:
I'd have thought this was worth saving if it's
related to the 5150 XT, or at
least it is to me. I'm trying and failing miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
Do you mean 5150 PC, or 5160 XT?
By "64K" MB, do you mean 16K - 64K? or 64K - 256K?
The 5150 PC had FIVE slots, cassette port,
available in 16K-64K (4116 8/1981) or 64K-256K (4164).
The 5160 XT had EIGHT slots, no cassette port,
available in 64K-256K or 640K.
One of these days, I've got to find the original power supply (black with
white switch), and take the extra drives, boards, ROMs, etc. out of my 16K
5150 before I sell it. Are people actually paying money for those things?
--
Grumpy Ol' Fred cisin at xenosoft.com
4:59 p.m.
At 05:50 PM 10/26/05 -0700, you wrote:
A white power switch? I've never seen one. And I've seen a couple of very
early PCs.
On Thu, 27 Oct 2005, Adrian Graham wrote:
> I'd have thought this was worth saving if it's related to the 5150 XT,
or at
> least it is to me. I'm trying and failing
miserably to find an XT with a
64K
motherboard,
purely because I guess people upgraded them as soon as they
could afford to.
Do you mean 5150 PC, or 5160 XT?
By "64K" MB, do you mean 16K - 64K? or 64K - 256K?
The 5150 PC had FIVE slots, cassette port,
available in 16K-64K (4116 8/1981) or 64K-256K (4164).
The 5160 XT had EIGHT slots, no cassette port,
available in 64K-256K or 640K.
One of these days, I've got to find the original power supply (black with
white switch), and take the extra drives, boards, ROMs, etc. out of my 16K
5150 before I sell it. Are people actually paying money for those things?
I don't know if they are or not but they soon will be. Remember that it
was only a few years ago that you could buy an Altair for a couple of
hundred dollars! It's darned difficult to even find an IBM PC, XT or AT now
(except for E-bay!). I've only seen three in the last three to four years.
Joe
--
Grumpy Ol' Fred cisin at xenosoft.com
9:22 p.m.
On 10/26/2005 at 8:59 PM Joe R. wrote:
>The 5150 PC had FIVE slots, cassette port,
>available in 16K-64K (4116 8/1981) or 64K-256K (4164).
Right, I bought the 16K version (3 rows of empty sockets) and populated it
with selected Intel 2109's (half-bad 2117's--you used the number after the
main part number to see which half to use). About half of the 2109's that
I tried were good enough to run in the PC as 16K devices. I got all the
2109's I wanted for nothing from the Intel sales rep, so it was worth the
trouble.
Cheers,
Chuck
10:12 p.m.
Fred Cisin wrote:
One of these days, I've got to find the original
power supply (black with
white switch), and take the extra drives, boards, ROMs, etc. out of my 16K
5150 before I sell it. Are people actually paying money for those things?
Yes. More if you leave them in :-)
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Want to help an ambitious games project? http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
10:46 p.m.
One of these
days, I've got to find the original power supply (black with
white switch), and take the extra drives, boards, ROMs, etc. out of my 16K
5150 before I sell it. Are people actually paying money for those things?
Yes. More if you leave them in :-)
Really??
I assumed that it would be worth more with IBM parts in it.
It's worth MORE with 2 SA455s (360K), an SA465 (5.25" 720K) and an SA350
(3.5" 720K) instead of IBM faceplate TM100s?
I figured that I should put it back to IBM FDC, IBM RAM, IBM serial,
IBM parallel, IBM CGA, IBM PS, instead of:
"Sunshine" EPROM programmer (replaced Apparat programmer),
JRAM (I don't remember what I did with my Boulder Creek ECC RAM board),
interface card for Atari Portfolio memory card drive (replaced P.O.S.T.),
Plantronics CGA,
most recent FDC in it was a Maynard, (at various times, it has had IBM,
Vista, Flagstaff (IBM modified for 8"), JRAM-FDC, Maynard)
I don't remember what the MBI add-on ROM was for.
I used it for 20+ years as a secondary machine for miscellaneous stuff.
--
Grumpy Ol' Fred cisin at xenosoft.com
27 Oct
27 Oct
3:28 a.m.
Fred Cisin wrote:
On Wed, 26 Oct 2005, Jim Leonard wrote:
Yes, but that's not what you wrote. You never said you'd put the original IBM
parts back in.
I love my 5150, but the RAM on the CGA card is going; I can see some bits
randomly toggling back and forth while in graphics mode (doesn't happen in text
mode, oddly). However, I'd STILL take an original CGA card because the clone
cards have different textmode fonts in ROM (presumably to avoid copyright
infringement) and all of the non-IBM fonts look quite horrid.
One of these days, I've got to find the original
power supply (black with
white switch), and take the extra drives, boards, ROMs, etc. out of my 16K
5150 before I sell it. Are people actually paying money for those things?
Yes. More if you leave them in :-)
Really??
I assumed that it would be worth more with IBM parts in it. I used it for 20+ years as a secondary machine for
miscellaneous stuff.
I still use mine for assembler programming. I figure if I can make it work on
a 5150, it will work anywhere ;-) But in all seriousness it forces me to
program well.
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Want to help an ambitious games project? http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
3:29 a.m.
On 27/10/05 01:50, "Fred Cisin" <cisin at xenosoft.com> wrote:
Do you mean 5150 PC, or 5160 XT?
By "64K" MB, do you mean 16K - 64K? or 64K - 256K?
The 16-64K PC.
The 5150 PC had FIVE slots, cassette port,
available in 16K-64K (4116 8/1981) or 64K-256K (4164).
In that case I DO have a PC, pity it's 250 miles away right now so I can't
go to check.....it's still the later board though, but it DOES have an
associated 5161 expansion unit that I've seen mentioned elsewhere as
somewhat of a rarity.
http://www.binarydinosaurs.co.uk/Museum/ibm/pc.php
The 5160 XT had EIGHT slots, no cassette port,
available in 64K-256K or 640K.
Check. There's one of those 6 feet away from where I'm typing this.
Time I wasn't here!
A
26 Oct
26 Oct
8:50 p.m.
I'd have thought this was worth saving if it's
related to the 5150 XT, or at
Waht is a '5150 XT'? The 5150 is the PC, an XT is a 5160.
least it is to me. I'm trying and failing
miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
Was there such a thing? I thought all XT motherboards used the 64K DRAM
chips. The 'stnadard' version has 64K-256K on board, there's a well known
mod to put 256K chips in the first 2 bnaks (giving 256K-640K on the
mainboard), IBM later sold boards like that.
Actually, come to think of it, I think the address decoder PROM on the XT
motehrboard would support 4816 (16K bit, 5V only) DRAM chops. But AFAIK
no such boards existed.
-tony
27 Oct
27 Oct
2:07 a.m.
On Thu, 27 Oct 2005 00:07:44 +0100
Adrian Graham <witchy at binarydinosaurs.co.uk> wrote:
On 26/10/05 23:44, "Chuck Guzis" <cclist at sydex.com> wrote:
It wouldn't be an XT, it would be a 'PC' and not many were made with the 64K
motherboard. That is called a 'PC-1' to differentiate it from a 'PC-2'
which had the 256K motherboard.
And all the PC (pre-XT) machines had the wider-slot-spacing of the original PC, so
it's not likely anybody 'upgraded' the motherboard in an original case to an
XT or XT-clone motherboard.
(I was one of the exceptions, I had to chop a non-standard-slot-spacing case for my first
'PC' machine which was an XT clone motherboard in a Leading Edge Model D case,
with a 63.5 watt power supply out of a PC that I had to physically remove from the
original IBM enclosure and just bolt the circuit board in the 'Model D' case. But
that was back when a working Model D was too expensive for me, as was a real XT Clone
Case, etc. etc. So I had a cheapskate franken-computer for a long while. Boy that was an
ugly and awkward hack looking back now.)
--
http://sasteven.multics.org/MacSE30/MacSE30.html
I've also got the guide by Purple Computing
for their Purple -2 Kit on how
to put 256K on your PC motherboard by cutting and changing a few jumpers
and then adding a board that attaches over the memory array that holds 64K
DRAMS. I'd forgotten that the original PC was limitied to 64K on the mobo.
I'd have thought this was worth saving if it's related to the 5150 XT, or at
least it is to me. I'm trying and failing miserably to find an XT with a 64K
motherboard, purely because I guess people upgraded them as soon as they
could afford to.
2:40 a.m.
On 10/27/2005 at 1:07 AM Scott Stevens wrote:
So I had a cheapskate franken-computer for a long
while. Boy that was an
ugly and awkward hack looking back now.)
"Standard" PC was a little loose in those days. I remember that the first
Compaq luggables had cards that fit and worked in a PC box, but the cover
was a very tight fit because the Compaq cards stuck up pretty far on top.
Way OT: Does anyone have a Xenix boot disk for a TRS-80 Model 16? Does it
require a hard disk or can you run with the two floppies?
Cheers,
Chuck
3:17 a.m.
On 27/10/05 07:07, "Scott Stevens" <chenmel at earthlink.net> wrote:
And all the PC (pre-XT) machines had the
wider-slot-spacing of the original
PC, so it's not likely anybody 'upgraded' the motherboard in an original
case
to an XT or XT-clone motherboard.
In that case even my cassette powered 5150 isn't a 'pc' then. Curses. :)
A
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-
ard＠p850ug1.demon.co.uk -
cclist＠sydex.com -
chenmel＠earthlink.net -
cisin＠xenosoft.com -
gilcarrick＠comcast.net -
julesrichardsonuk＠yahoo.co.uk -
jwstephens＠msm.umr.edu -
ploopster＠gmail.com -
rcini＠optonline.net -
rigdonj＠cfl.rr.com -
trixter＠oldskool.org -
waisun.chia＠gmail.com -
witchy＠binarydinosaurs.co.uk