Meaning of IntPullUp for I2C

  • Hello,

    what is the meaning of the entry “IntPullUp” for the native I2C driver?
    According to the document “Device Driver Documentation” (Version 1.04, 2015-04-09) the registry entry “IntPullUp” for the native I2C driver supports the following values:
    0: Disable internal pull-up (default)
    1: 100k pull-down
    2: 47k pull-up
    3: 100k pull-up
    4: 22k pull-up

    The description of the soft I2C driver states that the IntPullUp value is related to SCL and SDA.
    Because the F&S image for the efusA9 / efusA9X has this value configured to 1 and SDA and SCL are high I’m not sure about the meaning of this parameter.

    Best regards,

  • Hello,
    serveral I2C on EFUS has 4k7 on-board pull-ups (HW Docu.). So 100k pull-down is negligible and you measure almost 3.3V.
    Some ohter A9 boards do not have on-board pull-ups.

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.