I've used USB keyboards natively under WinME without any issues. They weren't modern gaming keyboards or anything, just your standard USB peripherals for office work made by A4Tech or Genius, but they worked well.

I think you can get slightly better USB input device support under Win98SE if you install NUSB. Stick with version 3.3 as the later ones can mess with your system files.

You may have luck by enabling "USB keyboard support" in BIOS, which perhaps can let you reach desktop enough so that you can press the next-next-next on driver installation dialog and afterwards have things work (until a different USB keyboard is connected, needing this procedure to be gone through again). Having a mouse to click the next buttons can work too. This is all assuming the USB keyboard in question is still a standard HID device and not something more fancy requiring dedicated drivers.

One HW option is to use a Pi Pico to 'reformat' new USB HID devices into more basic USB HID format supported by older machines. I'm part way through a bluetooth to USB 1.1 HID device for get new Apple bluetooth keyboard and mouse on a old iMac G4.

Pico can support both a host and device USB at the same time (using bit bashed USB for one of the ports) with a simple circuit. There are plenty of examples of host and device USB so it should just a matter of writing the converter part of the code...

I'd also already installed NUSB 3.6 so hopefully I haven't messed the system files up now. Also USB keyboard was enabled in the BIOS. As for the Pi Pico... That sounds like the most complex option but I'll have a look if nothing else works.

So here's where I'm at now. Device manager is showing a USB Human Interface Device with the exclamation mark of doom next to it. So if I go to update the driver I get a message telling me the best driver is already installed (See Screenshot). Then if I click finish it's asking me to insert the 98SE cd which I don't have. However I tried downloading the files it wants and pointing it at them instead but I'm met with a version conflict warning (See Screenshot). So if I already have the newer versions of these files then why does Windows want to install them from the cd anyway?

I have issues with my PS/2 to USB adapter with Win9x, too. It tends to lock the computer up during boot. It works if I plug it in after boot up. Basic USB keyboards and mice work fine, though.

Fireflyx91 wrote on 2023-12-08, 16:39:

I've heard the cheap little usb to ps/2 adapters are pretty useless

Depends. They physically adapt from USB to PS/2 connectors, nothing more - the keyboard then has to switch to talking the correct protocol, which older models knew how to do, but many modern ones do not. You just gotta use a keyboard supporting that. (Sometimes you also come across keyboards using this "in reverse" - PS/2 plug on kbd, using an adapter to plug into USB. Same principle, and probably easier to identify on e.g. eBay.)

fosterwj03 wrote on 2023-12-09, 03:06:

[my PS/2 to USB adapter] works if I plug it in after boot up.

I hope I'm misreading and you're not plugging anything into the PS/2 port after the machine has powered on? They're not meant to be hot pluggable, and doing that can burn out your PS/2 controller. Just sayin'.

elszgensa wrote on 2023-12-09, 11:10:

Depends. They physically adapt from USB to PS/2 connectors, nothing more - the keyboard then has to switch to talking the correc […]
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Fireflyx91 wrote on 2023-12-08, 16:39:

I've heard the cheap little usb to ps/2 adapters are pretty useless

Depends. They physically adapt from USB to PS/2 connectors, nothing more - the keyboard then has to switch to talking the correct protocol, which older models knew how to do, but many modern ones do not. You just gotta use a keyboard supporting that. (Sometimes you also come across keyboards using this "in reverse" - PS/2 plug on kbd, using an adapter to plug into USB. Same principle, and probably easier to identify on e.g. eBay.)

fosterwj03 wrote on 2023-12-09, 03:06:

[my PS/2 to USB adapter] works if I plug it in after boot up.

I hope I'm misreading and you're not plugging anything into the PS/2 port after the machine has powered on? They're not meant to be hot pluggable, and doing that can burn out your PS/2 controller. Just sayin'.

No, I meant that I plug the USB-side of the adapter into the USB port on the computer after it has boot into the Win 9x GUI. Windows 9x then detects the adapter, initializes the HID drivers, and then it works.

Yes, there ate two type of USB to PS/2 adapters.
- Passive, mechanical USB adapters without electronics
- USB to PS/2 converters (the bigger dongle type that looks like an USB pen drive).

Edit:
Adapter

Source: Wikipedia

Converter

Source: Wikipedia

OK, I misread the post. I was talking about one of these giving me problems in Windows 9x:

I just picked one of those little adapters up today because it was £2 so I figured why the hell not give it a try anyway. I didn't really have much hope for it and all that happens is the keyboard beeps on every key press but doesn't do anything else. I guess they probably do have their purpose for some older keyboards around between the transition time from PS/2 to USB but mine is too new.

I think the best option here is gonna be a full on converter. This was the only one I could find for under £100 but I'm still concerned about whether there could be any delays with using one of these.

https://www.digikey.co.uk/en/products/detail/ … DT60002/4438088

Does the machine have PS/2 or serial ports? You can temporarily connect PS/2 devices to click thru the "Add New Hardware" wizards. After that the keyboard should work. Another option is a serial mouse. Those "just work" without any dialogs popping up and are a convenient input device of last resort.