USB keyboard resetting

append delete Kuba Tyszko

Hi there, I finally joined the wagon and got the FPGA board, I successfully compiled the bitstream and it runs on the board, but I'm having an issue with my USB keyboard.
I tried 4 different keyboards:

CODE WASD - doesn't work at all (that's fine - it has LED's so I didn't expect it to)
Happy Hacking - doesn't work (it has custom micro controller, also fine)
Unicomp model M PS'2 via USB adapter - doesn't work (also ok, the adapter might be drawing too much)
cheap PC $9.99 keyboard - that one works but it's intermittent, it keeps resetting and I can only type a few characters at a time before it resets again

What could be causing this issue?


:: @Kuba Tyszko added on 29 Dec ’16 · 01:46

I just tested the same "half-working" keyboard using Diligent's keyboard sample code (the one that prints scan codes on the 7-seg displays). The behavior is the same - resets every now and then.
One observation I made is that as long as I keep typing (fast) the keyboard works, but as soon as it's idle it resets...

:: @Kuba Tyszko added on 29 Dec ’16 · 03:37

Oh well, 20 dollars later, I got it to work, bought another cheap usb keyboard, this time some logitech for $20 at a office supply store nearby - that one works okay.
So the conclusion is that not all cheap keyboards work (even without usb hub).
Must be internal chipset's HID compatibility issue...

Reply RSS


(Leave this as-is, it’s a trap!)

There is no need to “register”, just enter the same name + password of your choice every time.

Pro tip: Use markup to add links, quotes and more.

Your friendly neighbourhood moderators: Deft, gardners, Ralph Egas