Picade X HAT power disconnection doesn't work if i2c Device is connected to SDA and SCL Pins


#1

Hi there,

i have a Picade X Hat running in a project, using only the power on/off functions and the i2s DAC. I configured it with the legacy-python-drivers as described on github and everything works fine. I have clean sound and the Picade cuts Power to the Pi after shutdown. So far so good…

Now I wanted to add a Battery FuelGauge to the i2c interface using the SDA and SCL header. Communication with the Device works nicely, but as long as the Device is connected, the Picade doesn’t cut the power to the Pi properly after shutdown. It feels more like a restart.

When i disconnect the i2c Device, the power is cut properly and everything stays off.

Do you have any ideas how to fix this?

Greetings,

Alex


#2

What pins exactly are you connecting to? The SDA/SCL pins on the Hack Header on Picade X HAT?


#3

Yes, i’m connecting to the SDA/SCL pins on the Hack Header on Picade X HAT. But i have finally managed to get it working. The SDA/SCL lines of my FuelGauge circuit had 4k7 Pullups connected to the Battery Voltage, wich is still present after the shutdown of Picade X HAT. I just removed them from the circuit and now i only use the internal Pullups from the Raspberry Pi itself.

Everything works fine now. Sorry for bothering you.


#4

Glad you got it sorted! :-)