UniPi 1.1 Raspberry Pi 4 support

Dirk

Hi,

will UniPi 1.1 support Raspberry Pi 4 in the future? It's not working at the moment, although I thought there the GPIOs on the new Raspberry Pi are downwards compatible.

Any help is appreciated.

Thanks, Dirk

Martin Kudláček

Hi @dirk,
which access to the IOs do you use? Which OS image? The Evok has some troubles running on the Raspbian Buster and the fix is currently in the making.

Best regards,
Martin

Dirk

Hi @Martin-Kudláček,

basically I do not use an API and communicate with the board in Python directly. The software lives in docker containers. I use Raspbian Buster as host system at the moment. Docker container itself still runs on Stretch.

The latest version of http://wiringpi.com (which supports Pi4) does not work neither. Doesn't catch any change of GPIOs.

But you would not say, that it shouldn't run at all? I was wondering anyhow, because I thought the GPIOs should be backwards compatible.

Dirk

tomas_hora

@dirk The GPIOs should be compatible. Did you update to the wiringpi? http://wiringpi.com/wiringpi-updated-to-2-52-for-the-raspberry-pi-4b/

Dirk

@tomas_hora yes I'm running the latest wiringpi version 2.5.2.

Dirk

@Martin-Kudláček @tomas_hora

I've checked once again and the only pin I was able to read successfully, was

BCM 4 | wPi 7 | GPIO. 7 | IN
BCM 7 | wPi 11 | CE1 | IN

which is

I01 GPIO04 Digital Input Digital Input
I08 GPIO07 Digital Input Digital Input

in your documentation

Dirk

And one thing more I discovered. GPIO 34 which is GND toggel randomly between high and low.

martin_triska

Hello @Dirk,
our web-services API EVOK is tested with the RPi4. It uses pigpio library internally. As you mentioned, there are no changes in the GPIOs since previous versions of RPis. Do you have internal pull-ups turned on as mentioned in the manual?

Can you please post a schematic of your circuit?

Dirk

Hi @Martin-Kudláček,

thank you for your input. The problem were the internal pull-ups, set to low. Usually the python library, I'm using, does this job, but there seems to be a problem with the Raspberry Pi 4. Nevertheless I was able, to get everything up and running again, by setting needed GPIO pull-ups to high via /boot/config.txt. It's not the best solution, because it should be fixed software-wise. But it's the proof, that the problem is not related to hardware. Thank you so much for helping me, figure this out.

Dirk