1 Reply Latest reply on Nov 14, 2018 9:55 PM by AnjanaM_61

    CYW43438 on RPI, not able to communicate over UART to enable BT

      Hi all,

      I am using a Wifi/BT module containing CYW43438 connected to a RPI3CM. Wifi Works fine, BT no.

      I connected only Rx TX to RPI and starting hciattach on raspbian it goes in timeout:


      hciattach /dev/ttyAMA0 bcm43xx-3wire 115200 noflow -


      Initialization timed out.


      On the module RTS is float CTS is pulldown.

      Looking at the signals and decoding them, I see that the chip reply to the first command but not to the second one asking the chip name.


      0x01 0x03 0x0C 0x00          <-- reset chip          

      0x04 0x0E 0x04 0x01 0x03 0x0C 0x00

      0x01 0x14 0x0C 0x00          <-- asking for chip name

           -- no answer


      Can you help me to understand why the communication doesn't continue in order to setup the device completely?


      Linux raspberrypi 4.14.68-v7+

      bluez/stable,now 5.43-2+rpt2+deb9u2

      bluez-firmware/stable,now 1.2-3+rpt6

      pi-bluetooth/stable,now 0.1.9


      My impression is that H% 3wire  uart it is not properly configured and the chip look at the CTS signal anyway.

      If I remove the pulldown on CTS, disappear also the fir reply to the reset command. So it seems the chip take the CTS status into account.

      But I would like to use it managing only Rx and TX