HestiaPi Classic and I2C: access to pins without removing the shield?

Hi. Is it possible to connect an i2c device to a HestiaPi Classic with the shield in place?

I’d like to connect a humidity sensor, the best ones seem to use i2c, but the display/relays/buttons Hestia shield sits on the i2c pins (and I don’t think it uses them) and all the power pins. I can probably tap power somewhere but there’s only one pair of i2c pins. There’s a row of short pins on the back of the display shield, but I don’t know what they connect to: does anyone have or know how to figure out the pinouts? I downloaded some circuitboard files but I don’t understand what I’m looking at. Thanks in advance for any help with this classic hardware!

Checkout the pinout here

and make sure you use different I2C address than 0x76 for included sensor. Multiple I2C devices can use the same channel.
You would need to solder wires for your sensor. By the way, the included BME280 sensor does measure humidity too but I guess you want a second humidity sensor for another reason. Feel free to elaborate.

Thanks but I think you may have missed that I have a Classic not a Touch.

oops you are right. Yes the screen on the classic version uses too many wires and may block the I2C pins. I guess you can ignore my reply :stuck_out_tongue:

I think you are lucky…
pcb
This is the PCB you have on classic :point_up_2:t2:
pins labelled 2 and 3 next to the 3.3V are the I2C ones as you can see here:


and they are empty… so feel free to use these in terms of electrical connections. You would then need to add your own code to read, process, display etc the values from that sensor

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