Multi-IO Expander Beta discussion

[kriskeyman]

Just received Multi-IO expander, looking to connect it with Michigan F8R (always) & Disting EX (sometimes). I thought I had this figured out, but the ‘Pullup’ for each I2C on the back of the expander is giving me pause.

Multi-IO & F8R are in the same case… so I want to connect F8R GND/SCL/SDA to Multi-IO I2C-B GND/SCL/SDA, correct? Though I cannot find in any documentation if Pull-up on multi-IO i2c-B should be set to 5 volt or ‘none’.

For Disting EX in different case with XOXO I2C expander, I’d like to connect it to front of Multi-IO (assuming this is I2C-A?). If this is only connected sometimes (changed while power is off of course), should I2C-A pull-up be set to none, 3.3, or 5v?

Also, is this correct?
|  |  |  = none
0 0  |  = 3.3
|  0  0  = 5

Thanks for the help!