CORE 2 and how to chain 2x paHUB2

  • Dear, I using for my project a Core 2 controller and I need to have more than 6 I2C ports. I am developing under the graphical interface UIFLOW.

    In this contexte, I bought 2x pa.HUB2 units (I2C Hub 1 to 6 Expansion Unit).

    I changed the default I2C address of the second paHUB2 unit (from 0x70 to 0x71). Then I plugged this device to the channel 5 of the first pa.HUB2 unit.

    To test, i made a very simple program based on 2 sensors, a TOF sensors connected to the channel 0 of the first pa.HUB2. This first pa.HUB2 is connected to the port A of the CORE 2 controller.

    and a second sensor, ENV III sensors who is connected to the second pa.HUB2 unit, channel 0.

    When I run my simple program (based only on a loop to refresh 2 labels to get ENV III temperature and TOF distance), I got a BUS error.

    I am stuck on this, what I am doing wrong ?

    Thanks for your help


  • Hello @Thierry-REY

    a paHUB is only required if you have multiple I2C devices which use the same I2C address.

    In your case TOF (0x29) and ENV III (0x44/0x70) can be connected in parallel (using a HUB unit) - no need for a paHUB.

    Also, if for some reason you need both paHUBs you can connect them in parallel as well since you changed the I2C address of one already.

    Note: If you want to use the paHUB with the ENV III in parallel you'll need to make sure non of the paHUBs use I2C address 0x70 (as it seems to be already used by ENV III).

    Wikipedia article about I2C.


  • @felmue said in CORE 2 and how to chain 2x paHUB2:

    HUB unit

    many many thanks.