You would be, if you didn't have this ultra-cool TCA9548A 1-to-8 I2C multiplexer ... each of 0x70-0x77 addresses in order to control 64 of the same-I2C-addressed-part. Adafruit invests time and ...

This appears to be a TCA9548A-MOD board from adafruit. This board has a pull-up resistor on the nRESET line, so I don't expect this is the problem here. In order for the an I2C controller to access a ...

The test result was exactly the same, reproducing the problem. - Connecting MCU I2C master to a Adafruit TCA9548A breakout board, same MCU board but without assembled TCA9548A part. - SCL0 and SDA0 ...