First post, by Bjorn
I recently found a Compaq Deskpro 4/66i in an eWaste bin. (Such a pretty machine!) The first time I started it, it ran fine, but it quickly developed some issues. Apart from the onboard video memory going on the fritz (I'm working on a solution for that), the keyboard controller seems to have died.
I'm getting unrecoverable "303 - Keyboard Controller" errors every time I boot. The keyboard lights up briefly when the machine powers on, so I know it's getting power, but that's it.
The controller chip is not clearly labelled, but I seem to have found it. It's this Intel L3173056 chip:
I can't find a lot of info about it, but I suspect it's a (rebadged?) programmable controller of some kind not specifically for keyboards.
What I've tried:
* Multiple different keyboards (all work on other computers)
* Checked continuity between all the pins on the ps/2 port and the chip
* Contact cleaner in the ps/2 port
* Checked for corrosion around the pins of the chip
* Cleaned with isopropyl and compressed air around the chip
* Disconnected everything else on the computer
* Attached a mouse (for what it's worth)
* Contact cleaned and reseated the Dallas chip (for what it's worth)
* A few other things I can't think of right now
I'm still a bit of a novice when it comes to electronics, so I'd love to hear somebody else's idea before I start wildly desoldering and making an even bigger mess of things!