Trouble using I2C on T-QT Pro
I'm using an Adafruit sensor that I've connected via the Stemma port on the T-QT Pro and sensor. I've tried assigning the SDA and SCL ports to 44 and 43, but am not receiving any data. I've also run a few different I2C Scanner sketches, but nothing appears in my serial monitor.
What am I doing wrong here? Has anyone used the T-QT with Stemma/Qwiic before?
teastain last edited by
@mrudick1 I ran a temp sensor on I2C thru the Qwiic port with no problem on a LilyGO T-Display S3.
I have a GitHub Repo with a sample sketch : "LilyGO_tempsensor_hothead.ino "
Maybe you can read this over and get yours working?
teastain last edited by
LilyGo use the Qwiic "SIZED" connector but no standards as to pin function. It would appear that SDA and SCL are wire/pin swapped at the connector and would require that your cable be cut and re-soldered to the swapped wires.
I got lucky and my T-Display was GND, V+, SDA, SCL same as qwiic.
You may try swapping 44, 43 with 43, 44 (!!!) might work. but wire swapping is best.
Please let me know what you find out!
@teastain Hey Terry. Thank you so much for the guidance! Plus I would've pulled my hair out trying to figure out that SDA and SCL were swapped! I started down the rabbit hole and then wasn't sure if I had to go through the whole process of enabling I2C, which is a bit beyond my knowledge.
I'm trying to connect an Adafruit BNO055 IMU to the LilyGo. The weird part is that when I run a port scanner I get absolutely no serial output. This is what I used: https://playground.arduino.cc/Main/I2cScanner/. I also tried to specify ports 43 and 44 in the scanning, and still nothing. The T-QT doesn't seem to have any default SDA/SCL ports and my understanding is that I could use any of the open GPIOs.
Anyway, thanks a ton for your help. I will give this a shot and let you know.
@teastain What a shitshow! First my Arduino IDE got really funky and wasn't able to connect to Serial. I didn't realize I had upgraded the ESP32 board module and TFT_eSPI lib to the latest, neither of which work. I backed out of the newest TFT_eSPI lib and then twice downgraded the Expressif module to 2.0.4. And lastly, I put the pinMode for SDA and SCL in the setup() function, but that somehow borked the pinouts.
I have everything running smoothly now and was able to just reassign SCL to 44 and SDA to 43 without have to cross the wires.
I'm am greatly appreciative of your help. You got me on the right tack with your code and pinmodes. THANK YOU!