2 Replies Latest reply on Jan 23, 2018 10:47 PM by sujayy_46

    Is ANCS caused PUART(TXD) problem???

      CYW20706 uses PUART to communicate with MCU(sub).


      The PUART pin is using GPIO pin D6 as TXD and C5 as RXD.


      If only ANCS is connected, or if HFP is connected, UART communication is good.


      However, when ANCS is connected and HFP is connected, UART TXD level is fixed high


      There is no problem with the connection of Android phone.


      Have you ever heard of this problem?

        • 1. Re: Is ANCS caused PUART(TXD) problem???

          Please review any further findings after further testing on the previous issues.


          Once connected to ANCS and then connected to HFP,

          Something seems to hold the pin high in the chip.


          In this situation, I set the pin to GPIO and checked the status of PULL UP and PULL DOWN.

          The pin was slightly higher than the middle, not the PULL_DOWN.

          and it went up slightly.



          wiced_hal_gpio_configure_pin(WICED_P31, GPIO_OUTPUT_ENABLE | GPIO_PULL_UP | GPIO_PULL_DOWN, GPIO_PIN_OUTPUT_LOW );

          wiced_hal_gpio_set_pin_output(WICED_P31, 0);

          wiced_hal_gpio_set_pin_output(WICED_P31, 1);



          I attach the log.

          iOS_HFP_ANCS.txt is connected to the HFP first and then connected ANCS later.

          iOS_ANCS_HFP.txt is connected to the ANCS first and then connected HFP later.

          • 2. Re: Is ANCS caused PUART(TXD) problem???

            Which version of WICED are you using? Would it be possible for you to share your project?

            Are you sure you are not configuring the pin D6 for any other functionality other than PUART Tx pin(P31)?