Pico RGB Keypad stability

Discussion Raspberry Pi
1

Hi all,

I ordered a Pi Pico with pre-soldered headers and a Pico RGB keypad. I plugged them together and then loaded up the MicroPython demo - all the keys lit up white, which is a good start.

Unfortunately, most of the keys are not working very well - a few of them are not too bad, in that the keypress is detected quickly, turning the key green. Most of them are poor, in that the keypress will eventually be detected if the key is “mashed”. A couple of them are so bad that I have only ever got them to light up once or twice. In general the keypad is completely unusable in a project.

I have tried cleaning the contacts of the keys and on the PCB with a rubber and then cleaning them with alcohol, but this hasn’t improved things. I have also tried with and without the locating bolts - this has a small effect, in that the performance is worse with the bolts. The behaviour is the same when the keypad is rotated 180 degrees.

I’ve tried tweaking the demo a bit for diagnostics - for example, I toggle the Pico’s LED with every keypad scan, so I can see that the Pico is in general “alive”. Likewise, I have tried calling keypad.get_button_states() from Thonny, the results of which confirm what I am seeing in the demo i.e. mostly 0 is returned.

I am at a bit of a loss here - did I just get a bad PCB, or have others seen this behaviour? I used to have a rubber-key ZX Spectrum back in the day, so I know what to expect from “dead flesh” keypad technology :-)

Thanks for any help,
Darren

2

I noticed mine wasn’t registering presses at well to start with, it was because I had tightened the whole thing too much. I found loosening to a point where the nuts were sitting at the end of the threads worked best for me.

3

Update: I emailed Pimoroni and they immediately sent me a replacement keypad and paid for me to send the faulty one back to them for investigation. The replacement is working perfectly, so I am a happy bunny :-)