Help with Octek Fox M 286 (broken chip)

Discussion about old PC hardware.

Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2017-12-04 @ 23:52

Hello,
Bought this board today, seemed to be in perfect shape for something built 26 years ago. But upon closer inspection I found one of the chips to be broken (split in two, as if hit with great force): it's the one labeled PAL 089-001. Removed the label, the chip is a PAL16L8BCN, which according to the datasheet is a "Programmable replacement for high-speed TTL logic". How screwed am I? Any chance of reviving this board? As it is now, with or without the broken chip, I get a series of three short beeps after power-on.

octek_fox.jpg
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby .legaCy » 2017-12-05 @ 00:08

Such a nice board, its sad that is happened.
maybe any luck on ebay finding a replacement? or a junk board that can donate this IC ?
User avatar
.legaCy
Member
 
Posts: 486
Joined: 2016-4-08 @ 23:11
Location: Brazil

Re: Help with Octek Fox M 286 (broken chip)

Postby FesterBlatz » 2017-12-05 @ 00:11

I'd say your changes are pretty poor, unfortunately. The problem is whatever function that PLD was programmed to perform is unique to that board. In order to repair it, you'd need to find someone with the same motherboard who's willing to send the PLD to someone else with a device programmer. Assuming the device wasn't locked when it was programmed by the manufacturer, it could be interrogated to read the logic out of it and written to a new device.

Hoepfully you'll get lucky and someone else here has that same motherboard...I have a device programmer that could handle the rest.
Last edited by FesterBlatz on 2017-12-05 @ 00:12, edited 1 time in total.
User avatar
FesterBlatz
Member
 
Posts: 166
Joined: 2016-12-05 @ 13:49

Re: Help with Octek Fox M 286 (broken chip)

Postby bloodbath2you » 2017-12-05 @ 00:12

oouch, i have a similar mobo, an octek fox II, you could remove the sticker so we can read whats behind it.

my guess its a programable array logic chip, kinda difficult to replace because they need to be burnt like an eeprom.
bloodbath2you
Newbie
 
Posts: 26
Joined: 2015-9-09 @ 01:11

Re: Help with Octek Fox M 286 (broken chip)

Postby keropi » 2017-12-05 @ 00:55

it's a PAL like exactly like others mentions - says that on the label and for that age it's 99,99% to be one unfortunately....
User avatar
keropi
l33t++
 
Posts: 6573
Joined: 2003-9-08 @ 06:45
Location: Greece

Re: Help with Octek Fox M 286 (broken chip)

Postby Jo22 » 2017-12-06 @ 02:51

FesterBlatz wrote:Hoepfully you'll get lucky and someone else here has that same motherboard...I have a device programmer that could handle the rest.

As far as I know, the Schneider Euro AT had a Headland chipset, too. With two PALs, even.

Edit: Some universal programmers (G540, etc) claim to be able to measure the outputs of such chips.
Maybe there's a chance to make a duplicate ?
"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//
User avatar
Jo22
l33t
 
Posts: 2916
Joined: 2009-12-13 @ 07:06
Location: Europe

Re: Help with Octek Fox M 286 (broken chip)

Postby jesolo » 2017-12-06 @ 07:38

Will the TL866CS Pro be able to read such PAL chips?
Reason for me asking is that I recall having a 286 motherboard with a Headland chipset.
If it also has two PAL chips, then maybe I can give it a try?
User avatar
jesolo
Oldbie
 
Posts: 1449
Joined: 2014-6-24 @ 19:04
Location: South Africa

Re: Help with Octek Fox M 286 (broken chip)

Postby SSTV2 » 2017-12-06 @ 20:55

Actually, there is a chance of restoring chips contents if the DIE crystal did not crack together with its plastic case. The most difficult part would be forming good connections with remnant microscopic bond wires.
User avatar
SSTV2
Member
 
Posts: 204
Joined: 2014-11-19 @ 20:30

Re: Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2017-12-06 @ 22:14

Thanks everyone for your answers and advices.
Unfortunately, finding someone willing to risk his board to send me (or to someone else) the chip for copying seems like an impossible task. (more likely to someone else, as I know nothing about the devices used to read and program these things).

Also, for those suggesting other boards with PAL chips, I believe that the chip should have the exact same label (PAL 089-001) for it to have a chance to work.

SSTV2 - this crossed my mind, actually. The die might be in one piece, as the chip is not cracked right in the middle - you can see the end of the metal substrate where the split is. However, at a hobby/amateur level I don't think I'm up to this task to even try it...

broken chip.jpg
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby align_left » 2018-1-16 @ 18:41

If you're still searching, i have both, a Fox M 286 and a programmer.

foxm.jpg
align_left
Newbie
 
Posts: 7
Joined: 2014-2-13 @ 12:52

Re: Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2018-1-17 @ 00:01

Still searching, PM sent.
Thanks.
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby align_left » 2018-1-17 @ 16:09

It seems that they can't be read out with a normal Programmer (i have the TL886CS)...

http://www.vcfed.org/forum/showthread.p ... rade-chips

If there is a way, let me know and i can programm a GAL which seems to be working.
align_left
Newbie
 
Posts: 7
Joined: 2014-2-13 @ 12:52

Re: Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2018-2-06 @ 01:57

Looks like i found the datahseet/application notes of the Headland chipset. At the end, a schematic of a demo 286 board along with the PAL equations!
I've traced most of the pins of the broken PAL and they coincide with the schematic. So i'm pretty sure that my board will happily boot again. I just need to figure out how to translate what's below into a JEDEC file to program it in a GAL16V8.
PALeq.png

Headland GC101-102.pdf
(3.89 MiB) Downloaded 6 times
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby SSTV2 » 2018-2-06 @ 02:35

Neat, how thoughtful of the chipset manufacturer. The equations are very simple, but the main question is... wether input pins of that broken PAL chip are assigned the same way as in the given schematic. I'd suggest you to use Atmel's freeware WinCUPL to create equation project and generate jedec file.
User avatar
SSTV2
Member
 
Posts: 204
Joined: 2014-11-19 @ 20:30

Re: Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2018-2-06 @ 23:01

SSTV2 wrote:I'd suggest you to use Atmel's freeware WinCUPL to create equation project and generate jedec file.


Played a little with the program, it's way more complicated than i anticipated. Anyone that has experience with this stuff and is willing to compile the jedec file for me will be rewarded with my eternal gratitude. And a beer.
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby Auzner » 2018-2-07 @ 02:28

Just playing around with it I got something to compile. It's a start?

Code: Select all
Name     286fix ;
PartNo   PAL16L8 ;
Date     2/6/2018 ;
Revision 4/12/1988 ;
Designer Headland Technologies ;
Company  Vogons ;
Assembly None ;
Location retro basement ;
Device   G16V8 ;


/* Device modes */
/* Registered=G16V8MS */
/* Complex=G16V8MA */
/* Simple=G16V8AS */
/* Auto=G16V8 */

/* Inputs */
PIN 1 = RAM1RAS ;
PIN 2 = RAM0CAS ;
PIN 3 = RAS6080 ;
PIN 4 = RAS40 ;
PIN 5 = MEMW ;
PIN 6 = RAM1CAS ;
PIN 7 = RAM0RAS ;
PIN 8 = EMEMR ;
PIN 9 = XA0 ;
PIN 11 = XBHE ;
PIN 16 = ERD ;

/* Outputs */
PIN 12 = !CAS1H ;
PIN 13 = !RAS1 ;
PIN 14 = !CAS1L ;
PIN 15 = !RAS0 ;
PIN 17 = !CAS0H ;
PIN 18 = !CAS0L ;
PIN 19 = !RAS ;


RAS = EMEMR & MEMW & ERD ;

RAS0 =
RAM0RAS & !EMEMR & !RAS40
# RAM0RAS & !MEMW & !RAS40
# RAM0RAS & !EMEMR & !RAS6080
# RAM0RAS & !MEMW & !RAS6080
# RAM0RAS & !ERD ;

RAS1 =
RAM1RAS & !EMEMR & !RAS40
# RAM1RAS & !MEMW & !RAS40
# RAM1RAS & !EMEMR & !RAS6080
# RAM1RAS & !MEMW & !RAS6080
# RAM1RAS & !ERD ;

CAS0L =
!XA0 & RAS40 & RAM0CAS & !EMEMR
# !XA0 & RAS40 & RAM0CAS & !MEMW ;

CAS1L =
!XA0 & RAS40 & RAM1CAS & !EMEMR
# !XA0 & RAS40 & RAM1CAS & !MEMW ;

CAS0H =
!XBHE & RAS40 & RAM0CAS & !EMEMR
# !XBHE & RAS40 & RAM0CAS & !MEMW ;

CAS1H =
!XBHE & RAS40 & RAM1CAS & !EMEMR
# !XBHE & RAS40 & RAM1CAS & !MEMW ;
User avatar
Auzner
Member
 
Posts: 320
Joined: 2014-1-24 @ 11:28

Re: Help with Octek Fox M 286 (broken chip)

Postby quicknick » 2018-2-07 @ 20:50

Thanks for your effort!
I played around with the above code but couldn't get it to compile. WinCupl gives me 20 warnings (or three fatal errors if i try device dependent compile; btw, i don't know what should i choose). The program seems rather unfriendly towards noobs like me and doesn't specify what the warnings are about. However the simulation program outputs a few files with different extensions, and in the .so file i get exactly 20 lines like that, first two as shown and 18 more followed by the pin names: [0033sa] Please note: jedec vectors cannot be created with undefined pin numbers.
User avatar
quicknick
Member
 
Posts: 143
Joined: 2017-10-30 @ 23:53

Re: Help with Octek Fox M 286 (broken chip)

Postby Auzner » 2018-2-07 @ 20:57

Oh, I think I had device as virtual when it compiled. I've never used this before either.
User avatar
Auzner
Member
 
Posts: 320
Joined: 2014-1-24 @ 11:28

Re: Help with Octek Fox M 286 (broken chip)

Postby Fanatik » 2018-2-09 @ 03:23

There's an Octek Fox on ebay right now. https://www.ebay.com/itm/OCTEK-FOX-II-2 ... SwZJBX~6bj
Fanatik
Newbie
 
Posts: 19
Joined: 2018-1-25 @ 13:43

Re: Help with Octek Fox M 286 (broken chip)

Postby Jed118 » 2018-4-14 @ 03:19

Hah, I JUST got this board, paid $30 for it. Goddamn thing doesn't like anything else but 60ns - crashes continuously on anything higher. I have it doing a burn in overnight.

This board replaces my other 286/16 board that suffered from a latent trace failure.
Jed118
Member
 
Posts: 321
Joined: 2015-2-03 @ 17:15

Next

Return to General Old Hardware

Who is online

Users browsing this forum: BLEXBot [Bot], carlostex, Exabot [Bot], Neco and 6 guests