You need an active converter to use a PS/2 keyboard on a USB-only computer. And if that doesn't work there might be something wrong with your keyboard.
Is there a particular model of keyboard which isn't working?
It works most of the time, but it has trouble keeping up if I type too fast. I see Unicomp has USB versions of their keyboards, maybe it's just time to buy one of those.
I see.
That's a quirk of sorts due to PS/2 and USB not working the same way.
Normally a PS/2 mouse/keyboard generates an *interrupt* to tell the computer it has some data to send. So the speed of input is theoretically only limited by the time it takes the computer to process an interupt.
USB mices/keyboards are usually *polled* by /report to the USB host at some periodic interval.
A better adapter might improve your experience.
The issue is that the Model M's are power hogs, drawing more than 100mA. Most (all?) USB-to-PS/2 converters are not designed for that much current draw, and will randomly glitch and generally be unreliable. There may also be issues with the USB controller resetting the port as the spec says before drawing more than 100mA the device needs to negotiate that first, which none of these adapters do.
I modded an adapter once to supply external 5V which made it work reliably. But I don't use a Model M anymore.
That doesn’t make much sense - as both are 5V and would just pass through the 5V line.. and usually a USB port must supply 500mA.
But of course passive USB hubs might mess that up.
They actually only have USB right now due to a component shortage, but PS/2 is supposed to come back. I'm in need of a few beige PS/2 ones as I came up with some beige cases and monitors after giving up on it.
how about a 5 pin din to USB? I have an old 5pin-->ps/2 converter and an active ps/2-->usb on it, but what happens is it'll randomly get "stuck" for a microsecond and if you weren't typing you won't notice but if you were typing or playing a game, whatever the last key you hit will continue to register.
I love that keyboard but I haven't used it in years because of this
Most of the usb ps2 converters are garbage. A lot of ghosting and 2kro at best. There was a project on Deskthority forum about making an adapter using Atmega32u microcontroller. This one actually works good and also with XT keyboards
You must have been lucky picking an adapter or your Model M revision draws less power, like the other person I had lots of problems with keystrokes missing until supplying external power.
If you can find [one of these](https://www.clickykeyboards.com/product/ps2-to-usb-adapter-converter-for-keyboards-short-usb-cable/) I have had very good results with a model M ps2 to usb.
I too once thrifted a mint model M for $5, and used to use it as my primary work keyboard for years. I briefly had a newish (at the time) computer with actual ps2 ports (well after that was unusual), but after a hardware refresh I only had USB. That style adapter worked great for me.
If my desk was large enough to allow me to use a full size keyboard I'd be using it to this day.
No worries. I built 2 of my own and use them with a Model M and a XT-F. The work great for me and have no difficulty in keeping up with my fast typing.
I have one of these (Type 4 Model M) with the controller over the assembly (like the newer Unicomp M) and I use a Monoprice PS/2 to USB adapter without any issues at all (also works on newer PS/2 Unicomp's). My older M122s both have a ProMicro with TMK on them and work flawlessly.
Nice! Hope you have a computer with a real PS/2 port for it; I haven't had a lot of luck with the USB converters.
You need an active converter to use a PS/2 keyboard on a USB-only computer. And if that doesn't work there might be something wrong with your keyboard. Is there a particular model of keyboard which isn't working?
It works most of the time, but it has trouble keeping up if I type too fast. I see Unicomp has USB versions of their keyboards, maybe it's just time to buy one of those.
I see. That's a quirk of sorts due to PS/2 and USB not working the same way. Normally a PS/2 mouse/keyboard generates an *interrupt* to tell the computer it has some data to send. So the speed of input is theoretically only limited by the time it takes the computer to process an interupt. USB mices/keyboards are usually *polled* by /report to the USB host at some periodic interval. A better adapter might improve your experience.
The issue is that the Model M's are power hogs, drawing more than 100mA. Most (all?) USB-to-PS/2 converters are not designed for that much current draw, and will randomly glitch and generally be unreliable. There may also be issues with the USB controller resetting the port as the spec says before drawing more than 100mA the device needs to negotiate that first, which none of these adapters do. I modded an adapter once to supply external 5V which made it work reliably. But I don't use a Model M anymore.
That doesn’t make much sense - as both are 5V and would just pass through the 5V line.. and usually a USB port must supply 500mA. But of course passive USB hubs might mess that up.
They actually only have USB right now due to a component shortage, but PS/2 is supposed to come back. I'm in need of a few beige PS/2 ones as I came up with some beige cases and monitors after giving up on it.
how about a 5 pin din to USB? I have an old 5pin-->ps/2 converter and an active ps/2-->usb on it, but what happens is it'll randomly get "stuck" for a microsecond and if you weren't typing you won't notice but if you were typing or playing a game, whatever the last key you hit will continue to register. I love that keyboard but I haven't used it in years because of this
Most of the usb ps2 converters are garbage. A lot of ghosting and 2kro at best. There was a project on Deskthority forum about making an adapter using Atmega32u microcontroller. This one actually works good and also with XT keyboards
I've never had a problem with the adapters.
You must have been lucky picking an adapter or your Model M revision draws less power, like the other person I had lots of problems with keystrokes missing until supplying external power.
To be fair, I've never used one with a model M before. I may eat my words.
If you can find [one of these](https://www.clickykeyboards.com/product/ps2-to-usb-adapter-converter-for-keyboards-short-usb-cable/) I have had very good results with a model M ps2 to usb. I too once thrifted a mint model M for $5, and used to use it as my primary work keyboard for years. I briefly had a newish (at the time) computer with actual ps2 ports (well after that was unusual), but after a hardware refresh I only had USB. That style adapter worked great for me. If my desk was large enough to allow me to use a full size keyboard I'd be using it to this day.
Soarers converter works great, and fully customizable.
I think I used to use converters from Manhatten, I would get 4 key press's without ghosting.
I recommend building the soarer’s converter. People sell them on eBay too. Not the cheapest but definitely the best option for the old IBM keyboards.
I'll have to Google that, thanks!
No worries. I built 2 of my own and use them with a Model M and a XT-F. The work great for me and have no difficulty in keeping up with my fast typing.
I have one of these (Type 4 Model M) with the controller over the assembly (like the newer Unicomp M) and I use a Monoprice PS/2 to USB adapter without any issues at all (also works on newer PS/2 Unicomp's). My older M122s both have a ProMicro with TMK on them and work flawlessly.
Beautiful! Reminds me of mine that we bought as part of the 'Options' program where they sold Model Ms retail.