24 Jan
2011
24 Jan
'11
10:41 p.m.
Hi guys,
It seems my 386 has gone off to join the Choir Invisible. I pulled the
motherboard to clean off some battery residue and other gunk, and
replace the RTC chip socket -- now it's completely dead. I'm getting
"D-SUB: NO INPUT" on the monitor, no beeps or noise from the board, no
signs of life whatsoever. The HDD spins up, and the lights blink, but
the brain isn't doing squat.
I did find a broken 14.31818MHz xtal which I've replaced, but still nothing.
I have a sneaking suspicion the through-plating on the RTC socket might
have gone iffy (I'll be breaking the plastic alignment bands on the
socket and soldering the top-side tomorrow) but on the off-chance this
fails to resurrect the board.. Does anyone have a 386 or 486
AT-form-factor PC motherboard kicking around?
The board I had was one of these:
http://stason.org/TULARC/pc/motherboards/I/INFORMTECH-INTERNATIONAL-INC-486…
Basically:
- Baby-AT -- fits in a mini-tower case, AT power supply
- AMD 386DX-40 CPU
- Socket for 387 or Weitek math coprocessor
- 8 sockets for 30pin SIMMs -- max 32MB, but I've been running this
one on 8MB. I've got a box of 72pin SIMMs too.
- I/O on expansion cards, or at least some way of disabling the
on-motherboard IDE controller. This thing needs to drive a Seagate ST21R
RLL controller and a WD WD1003-WA2 (not at the same time, of course!)
- A couple of 16-bit ISA slots (this board has 5, I need at least two)
I'm wishing I hadn't thrown out my old Pentium-P100 board... that would
have been just about perfect for this :(
Thanks,
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
25 Jan
25 Jan
10:51 a.m.
Philip Pemberton wrote:
Hi guys,
It seems my 386 has gone off to join the Choir Invisible. I pulled the
motherboard to clean off some battery residue and other gunk, and
replace the RTC chip socket -- now it's completely dead. I'm getting
"D-SUB: NO INPUT" on the monitor, no beeps or noise from the board, no
signs of life whatsoever. The HDD spins up, and the lights blink, but
the brain isn't doing squat.
...
The board I had was one of these:
http://stason.org/TULARC/pc/motherboards/I/INFORMTECH-INTERNATIONAL-INC-486…
...
Thanks,
You might want to try replacing the Dallas Battery backed up RAM as
well, they only last about ten years - perhaps the battery has shorted
and this is killing the data bus?
John :-#)#
4:44 p.m.
On 25/01/11 15:51, John Robertson wrote:
You might want to try replacing the Dallas Battery
backed up RAM as
well, they only last about ten years - perhaps the battery has shorted
and this is killing the data bus?
Tried with the DS1687 pulled, no joy. Date on the chip is only 2002, anyway.
5V is present on the BIOS ROM, haven't checked anywhere else.
Given the amount of Green Goo around the ni-cad battery, I'm thinking
one of the sockets has succumbed, and the dunk-and-scrub probably
finished it off. Either that or the contact cleaner I sprayed in the ISA
slots is shorting the thing out...
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
7:31 p.m.
----- Original Message -----
From: "Philip Pemberton" <classiccmp at philpem.me.uk>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Tuesday, January 25, 2011 4:44 PM
Subject: Re: WTD: 386 motherboard
On 25/01/11 15:51, John Robertson wrote:
Have you tried using one of those $5 ISA/PCI POST cards from Ebay? I was
working on a Pentium motherboard a few days ago that wouldn't even beep.
After checking the onboard fuse I plugged in the post card into a PCI slot
and all the voltages were there (except for 3.xV which is normal) but
absolutely no activity on the LED's. So I unplugged the ROM chip and plugged
it back in, the unit then fired up.
Most battery leaks tend to take out the keyboard lines which are in the
general area. Never had an issue with washing a motherboard with soap and
water and letting it dry in the basement for a day or two. If something
major is shorting the AT supply should not run.
You might want to try replacing the Dallas
Battery backed up RAM as
well, they only last about ten years - perhaps the battery has shorted
and this is killing the data bus?
Tried with the DS1687 pulled, no joy. Date on the chip is only 2002,
anyway.
5V is present on the BIOS ROM, haven't checked anywhere else.
Given the amount of Green Goo around the ni-cad battery, I'm thinking one
of the sockets has succumbed, and the dunk-and-scrub probably finished it
off. Either that or the contact cleaner I sprayed in the ISA slots is
shorting the thing out...
8:05 p.m.
On 26/01/11 00:31, Teo Zenios wrote:
Have you tried using one of those $5 ISA/PCI POST
cards from Ebay?
I'm aware of them, but I did NOT know they were that cheap...
*searches*
OK, so for $20 I've just netted myself a set of three -- a PCIe/MiniPCIe
one which should work nicely on the laptops and the spiffy new(ish)
desktop, a PCI/USB/parallel one for the other laptops, and an ISA/PCI
one for the 386.
(Well for $6 a piece, it's hardly worth *not* having the full set...)
I was
working on a Pentium motherboard a few days ago that wouldn't even beep.
... which is pretty much what the 386 is doing (or not doing).
After checking the onboard fuse I plugged in the post
card into a PCI
slot and all the voltages were there (except for 3.xV which is normal)
Why would it be normal for 3.3V to be missing? Was this an old board
which only supported 5V PCI?
Most battery leaks tend to take out the keyboard lines
which are in the
general area. Never had an issue with washing a motherboard with soap
and water and letting it dry in the basement for a day or two. If
something major is shorting the AT supply should not run.
I can't see any damage to the keyboard lines... I did resolder a
resistor in the battery-charge chain, and scratch some corrosion off the
battery feed track. The keyboard connector got off pretty lightly it seems.
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
8:24 p.m.
----- Original Message -----
From: "Philip Pemberton" <classiccmp at philpem.me.uk>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Tuesday, January 25, 2011 8:05 PM
Subject: Re: WTD: 386 motherboard
On 26/01/11 00:31, Teo Zenios wrote:
Sometimes the lines look intact but they are broken, I use a multimeter to
check point to point on any lines in the area of the leak, fixed a nice IBM
486slc2/66 board that way (broken keyboard line).
Yea, POST cards are super cheap these days and help diagnose issues, plus
the manuals tend to have all the beep codes for most BIOS makers. I have a
parallel port one for older laptops and the ISA/PCI one. The original PCI
slots are 5V only, forget when they went to 3.3VDC.
Why did you solder a resister in the battery charge chain, that would drop
voltage? I use a diode when switching to coin cell battery to keep the unit
Have you tried using one of those $5 ISA/PCI POST
cards from Ebay?
I'm aware of them, but I did NOT know they were that cheap...
*searches*
After checking the onboard fuse I plugged in the
post card into a PCI
slot and all the voltages were there (except for 3.xV which is normal)
Why would it be normal for 3.3V to be missing? Was this an old board which
only supported 5V PCI?
I can't see any damage to the keyboard lines... I did resolder a resistor
in the battery-charge chain, and scratch some corrosion off the battery
feed track. The keyboard connector got off pretty lightly it seems.
--
Phil. from trying to charge a battery that doesn't like
that sort of thing.
8:58 p.m.
On 26/01/11 01:24, Teo Zenios wrote:
Why did you solder a resister in the battery charge
chain, that would
drop voltage?
It's there to charge the nicad battery, and was already part of the
motherboard. I desoldered one leg (which had been eaten away) and
replaced it with a new part.
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
8:46 a.m.
Alexandre Souza - Listas wrote:
But I have found that after removing the batery the machine will boot,
though it will of course complain about the CMOS being corrupt. I seem
to remember that the OP said he had de-soldered the batery.
Cheers.
Phill.
It's there
to charge the nicad battery, and was already part of the
motherboard. I desoldered one leg (which had been eaten away) and
replaced it with a new part.
And remember: Sometimes when the battery goes flat, the computer does
not boot and looks dead!!! 
8:58 a.m.
Alexandre Souza - Listas wrote:
But I have found that after removing the batery the
machine will boot,
though it will of course complain about the CMOS being corrupt. I seem to
remember that the OP said he had de-soldered the batery.
Phil, I've seen many machines that wouldn't boot WITHOUT a battery. SiS
530 (K6, Pentium 200/233MMX, etc) is one that comes to mind. If you have a
dead battery OR no battery, zed is dead.
It's
there to charge the nicad battery, and was already part of the
motherboard. I desoldered one leg (which had been eaten away) and
replaced it with a new part.
And remember: Sometimes when the battery goes
flat, the computer does
not boot and looks dead!!! 
9:44 a.m.
At 07:05 PM 1/25/2011, Philip Pemberton wrote:
On 26/01/11 00:31, Teo Zenios wrote:
Hmm, I hadn't looked in a while. I have a PCI one I got somewhere.
There's quite a variety on eBay at ridiculous prices. Which ones are
the good ones? I'd rather pay $30 for a good one than 99 cents for bad one.
Or for that matter, a well-documented one. See one card's eBay text below.
- John
This is the MINT condition PC Analyzer / debug / POST Codes tester for IBM &
compatible PCs with ISA or PCI slot
It is fit for desktop computer
Four-bit code is displayed
It can diagnose the troubles of not only the Main board, but also the card itself
It can prevent the users misunderstood It is compatible with all sorts of the computers
including a wide range of Intel flat, AMD flat, and so on
The cause code is more accurate and reliable
It cannot stop in the course of functioning
The value of four-bit-code PC Analyzer's "initiative code" is specified and
it is "0000" or "FFFF".
Initiative code is clear at a glance
Does no harm to the devise while you insert PC Analyzer in ISA slot wrongly or rightabout
and make it functioned
Fully compatible with any kind motherboards which has the PCI and ISA bus slot
It is 100% NEW
Package included
1 x PC POST diagnostic card (PCI & ISA card)
1 x English Manual
Have you tried using one of those $5 ISA/PCI POST
cards from Ebay?
I'm aware of them, but I did NOT know they were that cheap... *searches*
OK, so for $20 I've just netted myself a set of three -- a PCIe/MiniPCIe one which
should work nicely on the laptops and the spiffy new(ish) desktop, a PCI/USB/parallel one
for the other laptops, and an ISA/PCI one for the 386.
25 Jan
25 Jan
11:25 a.m.
On 25/01/11 03:41, Philip Pemberton wrote:
Hi guys,
It seems my 386 has gone off to join the Choir Invisible.
[...]
I'm wishing I hadn't thrown out my old
Pentium-P100 board... that would
have been just about perfect for this :(
Hi guys,
Just found an old AMD K6-II/500 machine in the scrap pile. Turns out
it's got 192MB RAM, and an "all in one" motherboard with two ISA slots
and a bunch of PCI slots. But the good part is that it works with both
the Western Digital MFM and Seagate RLL controller cards!
The WD1003-WA2 needs to be set up in the BIOS -- as in, you need to set
the CHS values for the drive. Cycle power and it boots (if you've got
the cables wired correctly, that is!). The card appears to have no BIOS
of its own, so it has none of the auto-detection or other toys (e.g.
low-level formatter) that the Seagate has.
For the Seagate ST22R, you set the BIOS to "no MASTER/SLAVE HDD" on
either the primary or secondary channel (depending on how the controller
is jumpered) and let the controller's BIOS do the hard work. Even
simpler... It looks like it'll probably only work with Seagate drives,
though you'd pretty much expect that from a Seagate controller...
Another morning successfully wasted :)
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
2:27 p.m.
The WD1003-WA2 needs to be set up in the BIOS -- as
in, you need to set
the CHS values for the drive. Cycle power and it boots (if you've got
the cables wired correctly, that is!). The card appears to have no BIOS
of its own, so it has none of the auto-detection or other toys (e.g.
low-level formatter) that the Seagate has.
Unlike the PC/XT, the original PC/AT (IBM 5170) motherboard BIOS included
the hard disk driver routines to talk to an WD controller (or an IDE
drive, actually, sicne they look the same in software). Many of the PC/AT
disk controllers did not have BIOS ROMs on them as a result.
It's a pity in some ways. Putting the firmware to drive an interface on
the the same board as the interface would seem to be a lot more versatile.
-tony
2:35 p.m.
On 1/25/11 2:27 PM, Tony Duell wrote:
It's a pity in some ways. Putting the firmware to
drive an interface on
the the same board as the interface would seem to be a lot more versatile.
Yay SBUS and PCI! (for what PCI was *supposed* to be, and what
non-PC PCI cards are, anyway)
-Dave
--
Dave McGuire
Port Charlotte, FL
2:23 p.m.
Hi guys,
It seems my 386 has gone off to join the Choir Invisible. I pulled the
motherboard to clean off some battery residue and other gunk, and
replace the RTC chip socket -- now it's completely dead. I'm getting
"D-SUB: NO INPUT" on the monitor, no beeps or noise from the board, no
signs of life whatsoever. The HDD spins up, and the lights blink, but
the brain isn't doing squat.
Hae you looked for activity on the bus lines, processor pins, SIMM
sockets, etc? It may be soemthing obvious.
I did find a broken 14.31818MHz xtal which I've replaced, but still nothing.
I susepct that this is the crystal for the OSC pin on the ISA bus and
nothing more. It's used as a colour subcarrier master clock by CGA cards,
as master clock for soem other boards that can use an odd frequency
like that and very little else.
I have a sneaking suspicion the through-plating on the RTC socket might
have gone iffy (I'll be breaking the plastic alignment bands on the
socket and soldering the top-side tomorrow) but on the off-chance this
I asusme ther are internal signal layers too, so resoldering both
surfaces may not be enough.
fails to resurrect the board.. Does anyone have a 386
or 486
AT-form-factor PC motherboard kicking around?
A rater OT question ; Can uou buy new, at any price, a PC motherboard tht
will take ISA cards? Ive got a lot of number of special-purpose ISA cards I
have, and seen even more, but I guess if you want to use things like that
you have to keep an old machine running.
-tony
4:50 p.m.
On 25/01/11 19:23, Tony Duell wrote:
I have a sneaking suspicion it's a 4-layer board...
Hae you looked for activity on the bus lines,
processor pins, SIMM
sockets, etc? It may be soemthing obvious.
Not yet. If I get sufficiently bored in the not too distant future, I'll
probably build up an ISA bodge-board for the HP16500B and see what's
going on.
I susepct that this is the crystal for the OSC pin on
the ISA bus and
nothing more. It's used as a colour subcarrier master clock by CGA cards,
as master clock for soem other boards that can use an odd frequency
like that and very little else.
Fair enough.
I have a
sneaking suspicion the through-plating on the RTC socket might
have gone iffy (I'll be breaking the plastic alignment bands on the
socket and soldering the top-side tomorrow) but on the off-chance this
I asusme ther are internal signal layers too, so resoldering both
surfaces may not be enough. A rater OT question ; Can uou buy new, at any price, a
PC motherboard tht
will take ISA cards? Ive got a lot of number of special-purpose ISA cards I
have, and seen even more, but I guess if you want to use things like that
you have to keep an old machine running.
You can get PICMG-compliant single-board computers which will take an
ISA riser card. I've got one kicking around somewhere... if memory
serves it's an AAEON SBC-675 Socket370 Celeron board. Nice little thing,
essentially a full computer on a full-length board. About the same size
as a Western Digital WD1003 Winchester controller card actually.
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
4:57 p.m.
> A rater OT question ; Can uou buy new, at any
price, a PC motherboard tht
> will take ISA cards? Ive got a lot of number of special-purpose ISA cards
> I
> have, and seen even more, but I guess if you want to use things like that
> you have to keep an old machine running.
NEW I'm not sure. But certainly an used Pentium-4 board can be found. I
had a Asus one, and there were others 2-3 years ago
26 Jan
26 Jan
2:43 p.m.
> A rater OT question ; Can uou buy new, at any
price, a PC motherboard tht
> will take ISA cards? Ive got a lot of number of special-purpose ISA cards
> I
> have, and seen even more, but I guess if you want to use things like that
> you have to keep an old machine running.
NEW I'm not sure. But certainly an used Pentium-4 board can be found. I
had a Asus one, and there were others 2-3 years ago
3:32 p.m.
I suspect that keeping an original 5160 or 5170
running will be a lot
easier than keeping such a board running.
Probably, but it does not run altium designer, and when I need to do a
BGA design using very high-speed FPGAs, a 5160/5170 does not help me much.
Maybe using smartwork for DOS, who knows?
3:37 p.m.
I suspect that keeping an original 5160 or 5170
running will be a lot
easier than keeping such a board running.
Probably, but it does not run altium designer, and when I need to do a
BGA design using very high-speed FPGAs, a 5160/5170 does not help me much.
2:01 p.m.
Hae you looked
for activity on the bus lines, processor pins, SIMM
sockets, etc? It may be soemthing obvious.
Not yet. If I get sufficiently bored in the not too distant future, I'll
probably build up an ISA bodge-board for the HP16500B and see what's
going on. I asusme ther
are internal signal layers too, so resoldering both
surfaces may not be enough.
I have a sneaking suspicion it's a 4-layer board...
4907
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4908
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20 comments
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afra＠aurigae.demon.co.uk -
ard＠p850ug1.demon.co.uk -
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