Keyboard and mouse issues, RPi4

I am trying to get a new Raspberry Pi 4 set up. It was supplied by RISCOSbits with RISC OS 5.29 (19-Dec-20). The problem is that with one of our wired keyboards (a nice Cherry one) the typing is very unreliable, with keypresses and releases going missing, leading to missing or repeated characters. Also, if I move the (wireless) mouse in circles the mouse pointer fairly frequently sticks for half a second or so before resuming its movement. The same mouse does not seem to suffer this issue if I use a Maplin wired keyboard, though I was having missing characters, rather more rarely, with this too. A wireless Lenovo keyboard/mouse set I use with my work laptop exhibited no problems.

The main difficulty is that I am setting up the machine for my parents, and preparing to take it to them soon, and they have a Cherry keyboard. Having to buy a new keyboard will be a nuisance, especially if there is no guarantee it will work. The typical cheap flat modern ones won’t suit them anyway.

Andy at RISCOSbits has been very helpful and sent me a beefier power supply. This seems to have improved the keyboard performance, but it is still far from perfect and not acceptable.

The strange thing is that my RPi3, using the official Raspberry Pi power supply, is fine with the Cherry keyboard: rock solid.

I’ve not yet tried updating the ROM. I’ll have a go at that, but as far as I could see from the forum the last major improvement to USB handling came out in 5.28 in October that year.

This Maplin keyboard has started dropping characters as I have been typing the last paragraph.

Does anyone have any suggestions as to how I can get it working reliably? A powered USB hub might be an option, if it’s the power requirements of the keyboard, but again cheap ones can interact in nasty ways with a Raspberry Pi.

At the moment my fall-back plan is to set them up with the RPi3 and keep the RPi4 myself!

Unless its one of these RGB light infested gaming models, a USB keyboard should not need a powered hub, but trying one would isolate the keyboard from the Pi and if it worked would point to an issue with the keyboard. But as you’ve said the Maplin one is starting to play up, I’m suspecting the Pi. Have you tried each USB port in turn, including the USB 3 ports, with no other USB devices attached?

Yes, I should have said that, apart from removing an SSD mounted internally in the case, I’ve tried all the ports with nothing else plugged in.

Good news is that updating the firmware files seems to have fixed the problem. I downloaded the 5.28 ROM from this website, and the latest 5.29. I thought I’d try 5.28 stable first, and then noticed that most of the firmware files differed from what I had been supplied with. I’m afraid I cannot say what cured it, because I unscientifically changed all of them at once. But I know it’s the firmware because I have now reverted to the supplied 5.29 ROM and it’s all still working fine.

And the original power supply from RISCOSbits is happily powering the RPi4, processor fan, two SSD drives, the keyboard and two wireless mice, one attached direct and the other via the keyboard’s built-in hub.

Well it is good to know that fixed it.

It’s one of those cases where you feel a bit stupid about asking the question. But I hadn’t even thought about the firmware as a possibility. I don’t have a clear idea of its function. Does it just set up the system-on-a-chip and load the OS, or is the firmware code still present once RISC OS starts, and called by the HAL somehow?