6 Replies Latest reply on Jul 17, 2020 8:50 PM by AkJa_4647796

    SPI connection with TFT display?

    AkJa_4647796

      Hello, AnjanaM_61

      I am using Cybt-413034-02 custom board. I am trying to interface spi communication with TFT display.

      Can I use any gpio pin for spi communication?

      My pins are:

      Cs = P07

      Sci = P02

      Sdi = P13

      Sdo = P17

      2. I have connected directly TFT display pins to my cybt -413034 module pin? Is it okay?

      Because when I connect my display I get 4.2V on HCI CTS pin?

      And module remains in reset state?  What is the problem?

       

      On module ground pin I am getting a pulse. Attached below. What could be the error.

      Thank you.

        • 1. Re: SPI connection with TFT display?
          AnjanaM_61

          Hi AkJa_4647796

           

          Not sure why you saw glitch on HCI CTS pin. Please check the connections and ground.

           

          Any GPIO pin which mentioned as SuperMux Capable in the datasheet Table CYBT-413034-02 Solder Pad Connection Definitions , can be used for SPI.  However you need to set / configure the pins in your application. Otherwise it will take the default settings from CYBT-413034 platform file.

          Please refer to the example available in WICED SDK for reference : /20719-B1_Bluetooth/apps/snip/hal/spi_master

           

          You may also refer to blog here: CYW20719 Serial Peripheral Interface (SPI)

           

          SPI and HCI UART share same buffers. So it should not be used simultaneously.

           

          Please try with the demo example available and let us know if you face any issues.

           

          Regards,

          Anjana

          2 of 2 people found this helpful
          • 2. Re: SPI connection with TFT display?
            AkJa_4647796

            Thank you for your response. AnjanaM_61,

            I solved the problem by using SuperMux. By using it I have to use the platform file CYW920719Q40EVB_01. Earlier I was using CYBT_413034_Eval this platform file I think we can't change the CYBT_413034_Eval platform file using SuperMux?

            1 Does it affect if I use CYW920719Q40EVB_01 platform file? Or should I copy the SuperMux folder and paste it in cybt_413034_Eval platform file?

             

            2.. what are the chances module goes into reset state or any unknown state? Because on power up my module remain in some othe state as it doesn't excute the code?

            Some time I can see my module advertising soon after power up. But other time it doesn't advertise quickly?

            • 3. Re: SPI connection with TFT display?
              AnjanaM_61

              Hi AkJa_4647796 ,

               

              You can use CYBT_413034_Eval platform files only.

              However , super mux GUI may not be accurate.

              I would suggest you to directly use the APIs to configure the pin - wiced_hal_gpio_select_function in the application start.

               

              2.. what are the chances module goes into reset state or any unknown state? Because on power up my module remain in some othe state as it doesn't excute the code?

              Some time I can see my module advertising soon after power up. But other time it doesn't advertise quickly?

              A: Very rare chances for module to be in unknown state. Please share the project or any further details to understand your issue.

              Please make sure you have included the patch files as in the below KBA if you are using WICED 6.4 : Platform and New Patch Files For 20719B1 in WICED 6.4.0.61 - KBA228518  If not, you may face inconsistent behavior.

               

              Regards,

              Anjana

               

               

              • 4. Re: SPI connection with TFT display?
                AkJa_4647796

                Hello AnjanaM_61,

                 

                I had used apu but the problem is I want to use Wiced_P16 gpio. But in CYBT_413034_EVAL platform file under wiced_pkatform_pin_config.c , the WicED_p16 pin is kept RESERVED_2

                 

                Yes,  I am using Wiced 6.4 and have included patchfile as in the below KBA.

                Platform and New Patch Files For 20719B1 in WICED 6.4.0.61 - KBA228518

                • 5. Re: SPI connection with TFT display?
                  AnjanaM_61

                  Hi AkJa_4647796 ,

                   

                  If you can select any other pin other than P16 , please use that. Because I can't see Supermux enabled in the GPIO table of CYBT_413034 datasheet.

                   

                  One more thing , even if any pins are configured in wiced_pkatform_pin_config.c , you may reconfigure depending upon your user application. If you call wiced_hal_gpio_select_function  in the main application, it will be overwritten to the configuration in platform files. So no issues.

                   

                  Regards,

                  Anjana