This is mostly for myself but I figured I would post it here as well. After putting together and setting up my new 8×8 bi-color LED matrix and i2c control PCB from Adafruit, I got a script error saying “Error accessing 0x70: Check your I2C address”. When I run sudo i2cdetect -y 0, I get nothing, but the matrix is detected when I run sudo i2cdetect -y 1.
So apparently the original version ran i2c on #0, but now it is on #1. So the test scripts are looking on the wrong bus for the device. Making a change to Adafruit_I2C.py to reflect the proper device bus should fix the issue… I guess I will find out tonight.