Re: Need help with my first 486 boards.

Posted on 2018-01-04, 23:31

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Well, I am not sure if I have the right AMI BIOS code table, but 03 is BIOS checksum, 04 is keyboard controller. That would be a good starting point. However, the fact it's randomly alternating is worrying me, however, the card seems to have some sort of intelligency on its own. Typically, you …

---

Re: Dudes it is time to make a MOTHERBOARD, i know it wil cost dearly, but i will buy it!

Posted on 2018-01-03, 19:19

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I used to work for a company who did number of designs from 386 to SS7. It's not undoable, but you'd need a lot of dedication. One design took about a year, with two HW engineers working on schematics and then one or two layout guys routing the board. You need a good PCB software with multiple layer …

---

Re: Need help with my first 486 boards.

Posted on 2018-01-01, 09:02

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Good decision. I have a pile of boards like that waiting for the card too (I only have the PCI variant and had to purchase the ISA one 😀 )

---

Re: Need help with my first 486 boards.

Posted on 2017-12-31, 21:24

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

FPM RAM can be easily identified by the chips. As long as you can recognize the chip marking on that eBay picture, you're fine :) BTW: so far, I didn't really care about EDO/FPM. I didn't have the chance to actually get my hands on board that wouldn't accept EDO, so I'm putting EDO memory everywhere …

---

Re: Any Ideas? Soundblaster AWE32 CT3900 strange cable soldered on...

Posted on 2017-12-31, 21:18

by

by Kubik

in Marvin \ Sound

in Marvin \ Sound

I'm just guessing it's a noise fix, based on the fact this is in the analog part of the card, and the resistor value is too low for pull up 😀 but without having the card at hand and having chance to check exactly how's that connected, it's just a guess.

---

Re: Need help with my first 486 boards.

Posted on 2017-12-31, 19:21

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

No video would be one long, followed with two shorts. I'd recommend to use a diagnostic card, those are so cheap on Aliexpress that it's pretty much a no-brainer, and I wouldn't bother touching the board again before having a diag card at hand :) You probably want the one with both ISA and PCI: …

---

Re: Any Ideas? Soundblaster AWE32 CT3900 strange cable soldered on...

Posted on 2017-12-31, 19:07

by

by Kubik

in Marvin \ Sound

in Marvin \ Sound

That little block is 220 Ohm resistor. It looks to me more like a home made fix, the soldering and wire laying job is a bit... amateurish 😀 I'm guessing an attempt to decrease a noise level or something like that.

---

Re: Intel dropping UEFI CSM (legacy BIOS support) for new systems in 2020

Posted on 2017-12-24, 13:52

by

by Kubik

in Milliways

in Milliways

A modern OS should(?) still be able to detect them with its drivers if they don't rely on asking the BIOS about what devices are present. Detecting and configuring a device is a feature of PCI / PCI-X / PCIe since the very beginning. For PCI, AFAIK not necessarily. Plenty of PCI cards I know use …

---

Re: Need help with my first 486 boards.

Posted on 2017-12-23, 23:11

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It's a good buy. If some of them are rare, it's a great buy from collector's perspective 😀

---

Re: Impossible to solve SCSI problem

Posted on 2017-12-23, 07:23

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Could it simply be a problem in early PCI implementation on your board? I can imagine that bus master problems could lead to similar behaviour.

---

Re: Looking for a Quadtel 40 Pin Keyboard/Mouse Controller Chip

Posted on 2017-12-22, 22:53

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

PS/2 mouse is controlled by the same chip. Although on 386, PS/2 mouse isn't so common so the question is - what mouse type OP uses?

---

Re: Looking for a Quadtel 40 Pin Keyboard/Mouse Controller Chip

Posted on 2017-12-22, 21:14

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I believe you can replace it with pretty much any other PC keyboard controller, those are all based on the same Intel chip / core, just firmware is different, but all of them are supposed to operate in the same way. If you have another board with keyboard controller socketed, you can freely swap …

---

Re: Need help with my first 486 boards.

Posted on 2017-12-22, 21:01

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That crystal is most likely 14.31818 MHz, which is sort of a base frequency for PCs 😀 The chip next to it, made by Avasem, is a PLL clock generator that converts 14.31818 MHz to other PC frequencies - see http://pdf1.alldatasheet.com/datasheet-pdf/vi … ST/AV9107C.html

---

Re: Connecting DOS Machine to LAN

Posted on 2017-12-20, 05:46

by

by Kubik

in Marvin \ Software

in Marvin \ Software

I'm pretty sure there was DOS FTP program, at least that's what we were using in ancient times before Windows. That one will most likely need a packet driver.

---

Re: Most frustrating part of working on old computers?

Posted on 2017-12-19, 20:43

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I second taking cases apart - old Macs and PS2s drive me nuts, not mentioning the Indy I still didn't figure out. I never know if I am supposed to use force or I am breaking something as there's a hidden screw or tab I didn't notice.

---

Re: Connecting DOS Machine to LAN

Posted on 2017-12-19, 11:10

by

by Kubik

in Marvin \ Software

in Marvin \ Software

I'm glad it finally worked :) I am actually finding MS client pretty easy to use, but that probably comes with age. Anyway, next time, I recommend you to fix the floppy first, then use Brad Driver's netboot (http://www.netbootdisk.com), it's IMHO easier than MS client, at least for initial testing …

---

Re: Connecting DOS Machine to LAN

Posted on 2017-12-18, 18:15

by

by Kubik

in Marvin \ Software

in Marvin \ Software

IRQ and interrupt is the same thing :) (Interrupt ReQuest) I am out of ideas. I would guess another good reason for this behaviour is wrong media select (coax instead of twisted pair) but in that case, packet driver wouldn't be able to connect either. Could you post the .INI files generated or …

---

Re: Connecting DOS Machine to LAN

Posted on 2017-12-18, 12:44

by

by Kubik

in Marvin \ Software

in Marvin \ Software

Did you configure the card I/O and IRQ in MS client setup? What you're describing sounds like IRQ isn't getting through.

---

Re: PCIe floppy controller card? or PCIe -> PCI -> floppy controller card?

Posted on 2017-12-17, 10:37

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Floppy USB drives only support standard PC formats, usually 2 sides, 80 tracks and nine or eighteen 512 byte sectors starting at 0 (and even some chinese drives support 18 sectors only), so they won't create floppies usable on those computers. I'm using my USB Teac to create floppies readable on …

---

Re: PCIe floppy controller card? or PCIe -> PCI -> floppy controller card?

Posted on 2017-12-17, 04:41

by

by Kubik

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That sounds like faulty or cheap modern USB floppy drive to me. I have old Teac, NEC and iomega USB floppy drives and never saw anything similar, and I wrote a number of 1.44, 720 and Mac floppies on those.

---