Pimorini EnviroHaT mini LTR559 sensor not working with only I2C connection


I have a Enviro HaT mini from Pimorini. I wanted to use only sensor like BME280 and LTR559 for my project with Pico Hat mini connections so that I can plug in Automation Hat with main header.

When I connect enviro hat with the main header then light-procimity sensor works fine but if I want to use only 4-wire I2C connection then I get the error while accessing LTR sensor. The BME works though.

"OSError error 121 remote I/O error".

Are there some more pins the sensor could be using? The following link shows that the Hat uses 16 pins in total. I had tried connecting all 16 of them with wire but still the LTR sensor did not work. Does someone has an idea?

Just for confirmation, is it the Enviro pHat, Enviro, or Enviro+?

Best guess is your missing a ground connection. All the grounds with the black horseshoe shaped marker need to be connected.

I have Enviro HaT Mini.
I tried your trick,
With all the grounds connected----> No success
With 3.3 and both 5V pins connected-----> success!!

Thank you, and nice catch!!

Nice to hear you figured it out. You can plug multiple Hats in with this by the way.
pHAT Stack – Pimoroni