Incorrect I2C pull-up detection on QT Py RP2040

CircuitPython on hardware including Adafruit's boards, and CircuitPython libraries using Blinka on host computers.

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
Locked
User avatar
joeblubaugh
 
Posts: 2
Joined: Thu Jul 29, 2021 3:09 am

Incorrect I2C pull-up detection on QT Py RP2040

Post by joeblubaugh »

Twice in the last two days I've been using my QT Py RP2040 with the Stemma QT connector to talk to two devices. I'm initializing the i2c bus using the correct pins, but I get this strange error:

Code: Select all

>>> import board
>>> import busio
>>> i2c = busio.I2C(board.SCL1, board.SDA1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
RuntimeError: No pull up found on SDA or SCL; check your wiring
>>>
I've tried using the flash_nuke.uf2, reinstalling CircuitPython after nuking, rebooting the board, Safely ejecting the board, removing power, and then rebooting the board ...

User avatar
dastels
 
Posts: 15608
Joined: Tue Oct 20, 2015 3:22 pm

Re: Incorrect I2C pull-up detection on QT Py RP2040

Post by dastels »

What I2C devices do you have connected to the STEMMA-QT connector?

Dave

User avatar
joeblubaugh
 
Posts: 2
Joined: Thu Jul 29, 2021 3:09 am

Re: Incorrect I2C pull-up detection on QT Py RP2040

Post by joeblubaugh »

I have an APDS-9960, changed to a 0.91" OLED display.

I realized something today - if I plug this into a power adapter and not my MacBook, I don't encounter this issue. The uc starts up quickly and the application seems to work every time.

Locked
Please be positive and constructive with your questions and comments.

Return to “Adafruit CircuitPython”