2 Replies Latest reply on Aug 7, 2020 6:33 AM by CoGl_4382676

    CY8CMBR3102-SX1I interrupt line innactive


      I am trying to enable a cap-sense button in my application. The CY8CMBR3102-SX1I has I2C and 2 GPIO lines. I am trying to use one line (CS0) as a cap sense button. That part I have working. The cap sense button can be activated, and I verify that by reading registers that are internal to the CY8CMBR3102-SX1I.
      The second part is what I am having a hard time with. I want the other GPIO (GPO0) to be used as an interrupt line for the cap sense button. I want the line to change when the cap-sense button is pressed/released. Right now I see no change on the GPO0 line when the button is pressed or released. Here are the configs that I am loading into the registers at setup.


      Register Name          Register Address          Set Value
      Sensor_EN                     0x00                         0x0001
      FSS_EN                         0x02                         0x0000
      TOGGLE_EN                 0x04                         0x0000
      GPO_CFG                     0x40                         0x08
      SPO_CFG                     0x4C                         0x05
      LED_ON_EN                 0x06                         0x0001
      LED_ON_TIME             0x3D                         0x01


      Any ideas of what I could do to make  this work? I could poll the register, but it would consume much more power and be inefficient.


      Thanks in advance!

        • 1. Re: CY8CMBR3102-SX1I interrupt line innactive

          From the GPO and SPO config we can know that the GPO pin is configured to Open-Drain Low drive mode and you want the GPO pin keeps  low state in idle and send out a 20ms high pulse when sensor state changes.  Please note that an external pulled up resister should be placed for GPO pin when you choose Open-Drain Low drive mode, or it cannot output high.  If you don't have an external pull-up resister on GPO pin, please change GPO drive mode to Strong.

          • 2. Re: CY8CMBR3102-SX1I interrupt line innactive

            The output line currently does have an external pull up resistor with a value of 5k ohms. Also, I have tried taking that resistor off and changing the configs to the GPO strong drive mode, and that did not fix the problem either.
            That was a good idea though.