Fixing an IBM PC XT 5160 Motherboard

In this video I go through troubleshooting and fixing a motherboard from an IBM PC XT model number 5160.
Part 2 is LIVE here:
Building an IBM PC XT from SCRATCH
• Building an IBM PC XT ...
Mentions:
My 6502 Microsoft BASIC video: • Microsoft BASIC from 1...
Minipro can usually be downloaded from your package manager (i.e. brew install minipro / apt install minipro) - or here: gitlab.com/Dav...
www.minuszerod...
Minimum 5150/5160 config: www.minuszerod...
Faulty motherboard: www.minuszerod...

[@ThePodcastMan02]

This is exactly what I needed

[@TheParachutePeople]

Very good, im glad you were able to get it working.

[@ForgottenComputer]

Happy to see it worked, and can’t wait for more!

[@narutowindel]

That is a good sound I like it. Excited to see this more

[@Juanivirix]

Good job

[@AndersNielsenAA]

Thank you!

[@nuherbleath461]

I got one of these at a house clearance, first thing it did was blow a cap when i turned it on.

[@AndersNielsenAA]

I bet! I’m certainly happy I didn’t get hit with tantalum shrapnel. Checking the lines for shorts is no guarantee either.

[@freddyvretrozone2849]

Cool, check the ROM is not something I would check first. I have a 5160 to check as well, it is complete with the keyboard, but no screen.

[@ayan.debnath]

Pls post more tutorial videos. I am also trying to repair (battery damage) my TWO PC-XT motherboards with all components and cards in perfect condition.

[@DM-fz3ly]

Nice work getting to POST! Curious as to what your tablet is and what you are able to use it for?

[@AndersNielsenAA]

The tablet is a cheap table oscilloscope :) It works. Fnirsi 1013D

[@douggale5962]

Haha. You finally ran into a case where you actually wanted to concatenate files, and you still got bash redirection to do it! `cat` could have sworn you were going to finally give it more than one argument.

[@AndersNielsenAA]

I know, I know.. I have a special skill for doing oneliners in two lines and opposite :) Should’ve been: cat rom.bin rom.bin >> romx2.bin

[@douggale5962]

@@AndersNielsenAA Yeah, what you did was fine though because bash history did half of the work.

[@senilyDeluxe]

or just burn the bottom half of the ROM and ground the extra address pin. EDIT: or put a different BIOS on it and do the same with the other ROM and hook the extra address pin up to a switch. Switchable BIOS!

[@AndersNielsenAA]

@@senilyDeluxe I think the reason it didn’t work the first time was that the pin A15 is connected to is actually pulled high (or connected to 5V) - so this was easier. Alternatively I could’ve just burned only the top half but that seemed pointless. I guess I could check the technical reference to see how A15 is actually connected.. but for now it works.

[@senilyDeluxe]

@@AndersNielsenAA That would have been my other guess. Either the pin was high or floating.

[@terosaarela4555]

I wonder if my Schneider EuroPC is suffering from a bad BIOS ROM too, as it doesn’t POST either…

[@AndersNielsenAA]

Could also be a leaky BIOS battery that destroyed something. Since it's not an exact XT clone I would start by checking the data and address lines on the BIOS ROM for activity. Or remove it and read it - it looks socketed from what I can find online.

[@terosaarela4555]

Actually did pull it and was able to read it. Need to probe it to see if there’s activity. Thanks for the advice!

[@dontwonnatell]

Hi, I have a question to these yellow cables. I'm fixing an 5160 board that had the same modification. As I thought it's a custom mod I removed. Was fighting myself through different faults (capacitors, etc) but board does not come to life (followed steps on -0°). Do you have any idea what kind of mod this is? so maybe I could find additional hints what is wrong with my one. Followed the stops

[@AndersNielsenAA]

Those are not mods - they're factory installed bodges and without them the board absolutely wont work. I hope you took a photo before you removed them.

[@dontwonnatell]

nope, but you have everything on video so that I can reverse engineer. Thanks for making these kind of videos :). Saw boards of same year that do not have these installations and they work. Could imagine that some chips were out of stock, so they installed different ones and made manual modifications because of this. Now that I've removed the installation it is totally plausible that the board is not working (no IRQ0, etc) @@AndersNielsenAA

[@dontwonnatell]

for those who are interested as well, found a nice picture here: minuszerodegrees.net/patch_wires/5160_motherboard_with_patch_wires_1.jpg.

[@ThePodcastMan02]

Why'd you cover up the numbers at the bottom with a piece of paper

[@AndersNielsenAA]

I'm assuming a previous owner put it there to write some details that have since vanished :)

[@ThePodcastMan02]

@@AndersNielsenAA ah, ok instead of paper I have my motherboard's manufacturing number on it

[@ThePodcastMan02]

I also have an IBM 5160. I just need to repair it. This video will help me immensely

[@AndersNielsenAA]

Yay! That's what it's for :)

[@ThePodcastMan02]

@@AndersNielsenAA Thank you!

[@user-re7fn9yz7t]

name O&O

[@AndersNielsenAA]

Huh?