Re: Help (re)building a 486

Posted on 2021-05-01, 15:36

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It doesn't have PS/2 headers, so from your suggestions how would I connect both my IBM early PS/2 mouse and keyboard? Use that adapter cable for the keyboard and another solution for the PS/2 mouse? How would I connect that Ebay Header Adapter for the mouse? My monitor says "October 1992" and it …

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Re: Motherboard BIOS wont save

Posted on 2021-04-30, 14:55

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

There's definitely corrosion on that pin and the via that the trace disappears into.

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Re: Reviving a 486 MB

Posted on 2021-04-30, 12:57

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If it's a single-chip BIOS on a 486, there's 99% chance it will be a 64KB part. Either a 27C512 or W27C512 (Winbond EEPROM) should work. The latter are pretty cheap and still widely available and won't need a UV source to erase and re-programme if needed.

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-30, 08:03

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Do note that in the above images I have 256KB of cache fitted, but only jumpered for 64KB, with the original (2x) 16K tag chips fitted (I didn't have any other tag modules available to test it). So don't use it as a reference for how to configure a 256KB configuration - instead refer to the jumper …

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-30, 08:02

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

MR BIOS V016B401 (v1.65 for generic Symphony Labs Haydn chipset). Filename V016B401.zip File size 45.66 KiB Downloads 45 downloads

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-30, 07:59

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Filename FIC_386SC_A2_front.jpg File size 875.73 KiB Views 1068 views Filename FIC_386SC_A2_rear.jpg File size 856.78 KiB Views 1068 views

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-30, 07:57

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Front/rear board images: Edit: Actually, urgh, the board software has done some nasty downsampling to them... I'll try shrinking them by hand....

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-30, 07:42

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

So, this is not a match for you 2? http://www.win3x.org/uh19/motherboard/show/2358 (Note, I relabeled the page, it was saying something else and I added the actual chipset info). It is! That's the exact match. I looked through all the matching 82C460 Haydn boards and couldn't find a match, that …

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-29, 20:50

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just tested a Tx486DLC-40 in the motherboard, and with the MR BIOS rom loaded it correctly identifies it and exposes a "Enable/Disable 486 processor cache" option, which is nice. Can't figure out the cache settings though; as supplied, the board had eight 64k x 8 SRAM modules and two 16k x 4 TAG …

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Re: FIC 386SC - unusual behaviour with ISA POST diagnostic card

Posted on 2021-04-29, 19:45

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Interestingly this board also runs fine with a v1.65 MR BIOS image and detects as a generic Symphony SL82C461 chipset. No difference in POST card behaviour though, which is weird. Anyway, next job is to figure out the jumper settings for this board, as, alas, TH99 and UH19 both refer to a "revision …

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FIC 386SC - upgrades and testing

Posted on 2021-04-29, 18:59

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I received this board from Ebay today - it's in nice shape, other than being dusty and having a flat Dallas RTC: img_1951.jpg Initial testing shows that it works as expected: img_1949.jpg I intend to remove the DX-33 and the 20ns of 256KB 64KB cache and replace with a DX-40 and/or DLC-40 and a full …

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Re: What´s wrong with this FIC 486 PAK-3 ??

Posted on 2021-04-29, 08:23

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Wow, that Norton result is slower than several of my 20MHz 286 boards. Even without level 2 cache fitted the scores should be way, way higher. Obvious question though: is the turbo switch enabled? Does it use a keyboard combination to enable turbo rather than a physical switch perhaps?

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Re: 486DLC cache coherency blues and headaches

Posted on 2021-04-28, 13:55

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by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Can you link to that v1.65 82C391 MR BIOS image? I've dug through that thread and can only find the early one; I'm currently debugging my PC-CHIPS M321 with the v1.30 file, but I'd prefer to use the later one if at all possible. I put @jheronimus bundle of MRBIOS files here: http://vogonsdrivers. …

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Re: 486DLC cache coherency blues and headaches

Posted on 2021-04-28, 13:37

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Can you link to that v1.65 82C391 MR BIOS image? I've dug through that thread and can only find the early one; I'm currently debugging my PC-CHIPS M321 with the v1.30 file, but I'd prefer to use the later one if at all possible. I put @jheronimus bundle of MRBIOS files here: http://vogonsdrivers. …

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Re: 486DLC cache coherency blues and headaches

Posted on 2021-04-28, 08:47

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I found this post that lead me to a newer MR-BIOS ( 1.65 vs 1.3): https://www.vogons.org/viewtopic.php?p=953935#p953935 Can you link to that v1.65 82C391 MR BIOS image? I've dug through that thread and can only find the early one; I'm currently debugging my PC-CHIPS M321 with the v1.30 file, but …

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Re: PC-Chips M321 repair work

Posted on 2021-04-27, 14:57

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Not really progressed any further with this. I did receive a couple of NOS Amikey-2 controllers, but they don't appear to make any difference to the "Keyboard controller failure or keyboard not present" error; I do see the keyboard lights flash on start, so there's power getting there, but I've …

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Re: Bought these (retro) hardware today

Posted on 2021-04-27, 08:58

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by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Looks like that Officestation is a thin terminal device: https://www.plathome.co.jp/common/cat/pdf/L100.pdf So it's like 1-10 people are sitting in front of the same computer? Didn't know companies still used terminals when office computers are so cheap. Probably for companies that are too cheap to …

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Re: *nix software and systems

Posted on 2021-04-27, 08:47

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by megatron-uk

in Marvin \ Software

in Marvin \ Software

My first and only Linux experience was Slackware 1.0, loaded off about 60 floppies onto a 486. Never really got my head around it. That was when I was first getting into computers. Going to try a few more recent distros on a 775 system some time, but will probably never move away from Windows on my …

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Re: Bought these (retro) hardware today

Posted on 2021-04-27, 08:32

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Miphee wrote on 2021-04-27, 08:20: Got a CGA adapter and a bunch of random hardware. I don't really know what the Officestations are but just couldn't leave them. The Dell PSU is huge! Looks like that Officestation is a thin terminal device: https://www.plathome.co.jp/common/cat/pdf/L100.pdf

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Re: Why is Amiga so popular with retro community ?

Posted on 2021-04-27, 08:22

by

by megatron-uk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

But in usual Commodore fascion and ways, engineering and devellopment were downsized. There are so many stories, that people in the management up at the top, suddenly realised that they needed something. Then they would see if the engineers had anything that could be sold as something exciting. …

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