2 Replies Latest reply on Dec 7, 2017 12:31 AM by luduc_2887926

    CY8CMBR3 - pollig capsense only work once



      I designed a board using the CY8CMBR3108 chip, and made a capsense button on CS0
      When using it with an external arduino UNO, I can get the button status easily , using a modified version of the MBR3_Read_Status for arduino found on the web
      When doing the same thing, but with an attiny85, I have some troubles: I can get the status of the capsense button only once, at the second reading

      Maybe I am missing a point, like some timing issues?


      I am using a "software" I2C, but the fact that I can read, at least once, the capsense status may suggest that the I2C is workig, and my problem comes from somewhere else


      Thank you in advance for any help given!

        • 1. Re: CY8CMBR3 - pollig capsense only work once

          Hi Iudovic,


          Not familiar with Arduido tools.

          Are there any LED to indicates capsense button status? If LED blink can follow capsense button's ON/OFF status, this issue must be caused by host firmware or I2C bus

          How about contacting attiny85/Arduino's tech support?




          • 2. Re: CY8CMBR3 - pollig capsense only work once

            Hi Ryan,


            Thanks a lot for all your answers! I found out what the problem was:

            Using the tinyWireM library for attiny85, when receiving a 0 value (e.g when polling the buttons status and no one is triggered), the I2C break. I don't know yet why, but will investigate.

            A quick fix is to re-init the I2C ( tinyWireM.begin() ) just after a buttons reading, this fix the problem.

            Hope it will be usefull for someone else one day!


            Thanks you anyway for your time and for the other answers given ( I didn't thanks you before, sorry, was in a rush)