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Comment by dogma1138 | Hacker News Reader

Good luck using an AT keyboard today :P there are some USB converters. Some motherboards that offer PS/2 connectivity (rare, mostly "gaming motherboards" for n-Key rollover fanatics) but I don't even know if that chipset would do AT.

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The PS/2 keyboard interface is just AT with a mini-DIN connector instead of DIN. It's the same protocol.

I wish it were a lot less rare as few ps/2-usb converters are very good, especially with a Model M for some reason. I don't want to retire it, it's still in great condition, unlike the dozen or more other keyboards I've had that have died after a year or two.

I think I still have an old Silicon Graphics keyboard somewhere in the garage. Built like a tank, I'm pretty sure it would still work if I had a port to connect it to.

There aren't ports because there isn't support anymore. Intel doesn't support AT, I don't even think it supports PS/2 with most of it's chipsets.

The motherboards that do come with PS/2 usually implement their chipset.

Also PS/2 stopped being electrically compatible a while ago around about the same time that the combo Keyboard/Mouse PS/2 ports became available.

It offers pretty low current only about 250ma so you might have issues with older AT keyboards even if the chipset is still AT command compatible.

This stuff is in the Super I/O chip.

Super I/O is dead and gone for like well decades.

For Intel system super I/O was eaten by the ICH which initially kept compatibility with most Super I/O functions.

By ICH 6 or 7 which is around the mid 2000's most of those legacy features were all gone.

By 2008-9 the ICH was also gone and replaced by the PCH which doesn't have almost any compatibility or features with the Super I/O architecture.

What is the nuvoton superio chip on my ASRock z97 then?

Most like the same things the rest of them do like SMBus, temperature sensors, fan control and voltage monitoring. They also do the GPIO for various other features like resetting the bios or switching between different BIOS flash chips, more recently the LED controls on the newer motherboards and the error code segment display that is now used instead of the POST beeping sounds so you can actually know wtf is going on :)

Super I/O is not dead. It has the PS/2 keyboard and mouse ports for example.

I got the cheapest motherboard available that would work with the components I was getting and it happened to have ps/2 ports.

Even if you _have_ PS/2 connectivity, good luck getting it work with legacy hardware. E.g. an original Model M kbd will not work with most modern PS/2 due to electrical limitations (can't remember if it's non enough volts or not enough amps)

I'm typing this on a Model M from 1990 connected to a PS/2 port. It works just fine.

I think there is a simple hardware modification to make them work.

Only a few PS/2 -> USB adapters are fully functional according to the PS/2 specification. I use an adapter from Sanoxy [1] with my Model M and it works superbly. I have read of other Model M enthusiasts using the same one.

[1] https://www.amazon.com/SANOXY-PS2-Keyboard-USB-Adapter/dp/B0...

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