Re: SIS 496/7G rev 1.02 problems, RTC stops when computer is off, FDC failure when cold booting

Posted on 2021-02-17, 10:47

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Since the SiS 497 has an integrated real time clock, the motherboard is probably using that instead of a separate chip. So you may want to check the 496/497 datasheet (there's info about the RTC in page 73): SiS 496-497.pdf Try to follow the traces to see how it connects to the battery. If the …

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Re: SIS 496/7G rev 1.02 problems, RTC stops when computer is off, FDC failure when cold booting

Posted on 2021-02-16, 17:01

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If I were you I'd tried the following: - Check the voltage of installed battery. Possible short circuit draws battery in no time (besides other negative effects like heating up some elements and areas on MB). - Locate RTC chip and check if is cold. If it is noticeable warmer than other parts of MB …

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Re: What retro activity did you get up to today?

Posted on 2021-02-16, 12:18

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I've just bought LS-486e Rev:D with fried voltage regulator. Going to repair it tonight.

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Re: soundblaster 16 problem

Posted on 2021-02-15, 11:37

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

This is all great information. I will get to implementing the suggestions today or tomorrow. I want to thank everyone who replied and is trying to help me out. I dont know nearly enough about this stuff to do it on my own. Thanks again to everyone. Just found manual in English: EMM386.EXE manual …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-14, 21:12

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

All that extra crap would cost as much or more than a DIN to mini-DIN adapter dongle I got sick and tired searching for fancy slick DIN-miniDIN adapter so I made one myself from 10cm of ethernet cable, miniDIN socket salvaged from dead mobo and DIN plug (the only thing I had to buy). Works much …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-14, 10:54

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2021-02-13, 20:38: Done According to layout you are planning on using AT keyboard connector located on MB. Why don't you just place both PS/2 mouse and keyboard connectors on your board?

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Re: soundblaster 16 problem

Posted on 2021-02-14, 10:51

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Do MEM /C /P from inside DOS and post it here - looking at that list I don't see why you don't have a lot more free conventional memory. MEM /D /P give you more info. Moreover LH has its own parameters. It allows you to specify the memory region. Sometimes it's useful to toss some resident programs …

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Re: soundblaster 16 problem

Posted on 2021-02-14, 10:47

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I got the keyboard issue sorted. I found one at my moms house and it worked perfectly. I was able to get into the BIOS and change the settings for the 5.25 inch floppy drive. My issue at the moment is the autoexec.bat and config.sys files. Trying to get that precious free memory to actually run …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-13, 09:35

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2021-02-13, 03:24: froller wrote on 2021-02-12, 20:58: Does your one have 4 72-pin SIMM slots and VT82C41N soldered between two lower ISA slots along with some 74-series logic chip? Indeed It looks fully packed and not suitable for modding. At least on photos.

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-12, 20:58

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2021-02-12, 14:43: Good catch. I don't own a rev D personally, my rev C has no such footprint. Trying to solder that SOP in between ISA slots is gonna suck Does your one have 4 72-pin SIMM slots and VT82C41N soldered between two lower ISA slots along with some 74-series logic …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-12, 18:44

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Good catch. I don't own a rev D personally, my rev C has no such footprint. Trying to solder that SOP in between ISA slots is gonna suck Many things become possible if you have soldering heat gun and roll of aluminum foil. Just cover ISA slots with a paper napkin and 2 layers of foil and it should …

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Re: Retro Development

Posted on 2021-02-12, 11:46

by

by froller

in Milliways

in Milliways

Writing my own boot manager to load different OS'es especially different versions of DOS. Not yet much done. I still haven't managed to make it load DOS from other partition than first found FAT-16. However it already allows you to switch between DOS and OS/2. Sources are here. Help is welcome.

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-12, 10:04

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Oh by the way - as I'm sure you noticed from looking at the HT6542B datasheet's app notes - pins 28 and 39 are the mouse data and clock inputs. The chip also has output pins that need to be connected to the header (via the inductors of course) after being buffered through a 7406 inverter. There …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-11, 21:04

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Ok but could you please check the other pins on the DIP40 footprint to see if they are connected to anything at all? My goal here is to document the VT82C41N Had no luck. :( Pins 1, 2, 18 and 23 of VT82C41N are neither connected to any pin of DIP-40 nor to ISA slot nor to any via in approximately …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-11, 16:12

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

So you are saying that pins 1, 2, 18 and 23 on the VT82C41N do not have continuity to any of the pins on the DIP40 footprint? I say VT82C41N pins 1, 2, 18 and 23 are not connected to DIP-40 pins 28 and 39 . DIP-40 pins 28 and 39 known to match HT6542B pins for mouse data and clock. DIP-40 pins 28 …

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Re: Searching for redemption with my LS-486e (need help with MB repair)

Posted on 2021-02-11, 15:45

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

gerwin wrote on 2021-02-11, 14:22: feipoa wrote on 2021-02-11, 14:17: Wasn't there only one revision of the LuckyStar LS-486e which supported EDO? I forget which one it was now. SIS 496 'PR' Revision Northbridge supports EDO-RAM. Is SiS85C496 'NV' produced in 1997 capable of EDO?

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Re: Searching for redemption with my LS-486e (need help with MB repair)

Posted on 2021-02-11, 13:49

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Back in 2001 I bought some EDO RAM from eBay for my PC Chips M919 motherboard; the board was ruined thereafter. Booted it up and got an NT4 BSOD straight away. I put the original RAM back in, but I kept getting BSODs thereafter. The board had worked fine for years prior. The only thing I changed …

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Re: Owners of the Lucky Star LS-486E Revision D - PS/2 Mouse / Please help

Posted on 2021-02-11, 13:45

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Here's datasheet on Holtek HT6542B which looks a good replacement for VT82C41N. LS-486e Rev:D has similar schematics the one shown on typical application page for PS/2 mobos except additional inductors between CN3 pins and KBC. For test purposes these inductors can be replaced with jumper wires. …

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Re: Searching for redemption with my LS-486e (need help with MB repair)

Posted on 2021-02-11, 13:09

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

AFAIK EDO/FPM use 5 volts and SDRAM is 3.3V. Check the datasheets of your memory chips and see what they'll take. For sure they are 3.3V. Otherwise there no need of 3.3V LDO onboard of SIMM. I don't care of fried SIMMs. I have more of them either EDO 3.3V or 5V or FPM 5V. I'm afraid they damaged …

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Re: Searching for redemption with my LS-486e (need help with MB repair)

Posted on 2021-02-11, 12:44

by

by froller

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Continuing my adventures with LS-486e Rev:D I've managed to replace fried power BJT with new TIP127 and got 3.3V and mobo started with Am5x86-P75-133ADZ and 2x4MB FPM RAM. Then I decided to check if it supports EDO and installed 2x64MB EDO and mobo started and checked all 128MB and asked for floppy. …

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