SH1107 not working with Stemma QT

[jeremyamoore]

Was trying to get an SH1107 display working with an ESP32-S2 feather. The sample code says it cannot find the id 0x3D. Doing the i2c scan() also does not show it. I have some other Stemma QT boards that work fine, even before and after the display in the i2c path. Any ideas what else to try or do I just have a bad board? I did see someone else with a similar issue on this forum, and it was a bad board there. I have also tried with QTPY 2040 and the Metro ESP32-S2 express with same results.

Thanks - Jeremy

[dastels]

Did you enable the StemmaQT power?

The Feather ESP32-S2 also has a power 'switch' on the I2C port. You need to activate the power port by setting the control pin (GPIO 7) to an OUTPUT and LOW before accessing the I2C port

pinMode(7, OUTPUT);
digitalWrite(7, LOW);

Dave

[jeremyamoore]

I am using the CircuitPython I2C capabilities which should handle that automatically. I do get the green light on the board and the other boards I have daisy chained to it - A BME680, MPR121, and TLV493D all are working. Just not the display as it cannot even see the address. Swapping out the position in the chain does not change anything.

[dastels]

OK then, it does seem like a bad board. Which product is it?

Dave

[jeremyamoore]

Adafruit Monochrome 1.12" 128x128 OLED Graphic Display - STEMMA QT / Qwiic

https://www.adafruit.com/product/5297

[dastels]

Cool. Please email [email protected] with a link to this thread, your order number, and request the replacement of one Monochrome 1.12" 128x128 OLED Graphic Display - STEMMA QT.

Dave

[angelkjos]

I have a very similar problem. Feather ESP32-S2 chained via Stemma QT to BME688 and then chained again via Stemma QT to FeatherWing OLED 128x64.
BME688 works fine and reports data but the display is completely blank. Cannot get anything to be displayed even though I tried all examples given. Even tried hooking up the OLED directly to the stemma qt of the feather (without the bme688) but without luck.

The interesting thing is that an I2C scan sees the 0x3C address of the OLED but it does not work, and neither do the buttons.

[dastels]

I have a very similar problem.

Please make a new topic for your issue.

Dave