Is There a Reason Why I do not Have Control Over I2C-2 on my BBGW?


I was trying to rehash an older project w/ the Motor Bridge Cape and came across some odd issues. Here is the info. I am giving. If anyone needs additional ideas or logs, please let me know.

uname -r: 4.19.94-ti-r71


cat /etc/dogtag: Debian Buster IoT Image 2022-02-03

I ran ./ b/c of me having the 4.19.x kernel w/ the Buster Distro. For some reason, I had an older model of uboot, i.e. circa '18 on the eMMC. So, I removed it and am rebooting now.


P.S. I rebooted. The board is booting very fast these days. Good work fellows/gals. Anyway, here are the errors on output:

Traceback (most recent call last):
  File "./", line 20, in <module>
    from MotorBridge import *
  File "/home/debian/MotorBridge/", line 19, in <module>
    MotorBridge = SMBus('/dev/i2c-2')
  File "/home/debian/.local/lib/python3.7/site-packages/smbus2/", line 280, in __init__
  File "/home/debian/.local/lib/python3.7/site-packages/smbus2/", line 310, in open
    self.fd =, os.O_RDWR)
PermissionError: [Errno 13] Permission denied: '/dev/i2c-2'

I will check to see if I am missing i2c-2 on this Buster image.

hi @silver2row fixed last night…

open /etc/groups and add debian to the i2c line and reboot…


1 Like


Man…like candy! It works! I2C was only faulty for that reason. I was not part of the i2c group. There is also another way to add users to groups from the command line but that way in the file(s) is nifty. Thank you, sir.