6 Replies Latest reply on Sep 5, 2018 11:08 PM by user_9155550

    FX 3 USB boot fault

    user_9155550

      Hi,

       

      We made a wrong terminal connection of FX 3 and connected the RESET # terminal directly to the INT # terminal.

      As a result, I encountered a phenomenon that the USB BOOT operation does not work.

       

      The SPI boot operation works without problems.

      Where is the cause of the USB boot operation not functioning?

       

      What is wrong with directly connecting the RESET # pin to the INT # pin?

      Those who have knowledge please give us information.

       

      Best regards,

        • 1. Re: FX 3 USB boot fault
          srnt

          Hello,

           

          - Please let us know what is the PMODE line setting that you are using.

          - It is recommended to maintain a minimum reset pulse width of 1ms. Kindly, check if this is satisfied in your condition.

          - Please share the schematic of your design around the RESET# pin.

           

          Best regards,

          Srinath S

          • 2. Re: FX 3 USB boot fault
            user_9155550

            Hello, Srinath S-San

            Thank you for reply.

             

            (1)PMODE

            We use PMODE[2:0] line

            Z11 USB Boot

            0Z1 SPI Boot

            set above state with external switch's setting..

             

            (2)RESET# condition

            At Main power on , No reset pulse is applied

            When RESET# and INT# are disconnected, USB boot was possible even without reset pulse with our board.

             

            (3)Schematic

            Pls refer to attached PNG

            FX3_Circuit.png

             

            Regards,

            • 3. Re: FX 3 USB boot fault
              srnt

              Hello,

               

              - Can you please probe the RESET# pin on both the boot modes and share the same?

              - Also, let me know if the SPI boot mode works fine all the time.

               

              Best regards,

              Srinath S

              • 4. Re: FX 3 USB boot fault
                user_9155550

                Hello, Srinath-San

                 

                (1)INT# and RESET# pin Probe result

                Approximately 3.5 msec later from power on, the INT # pin outputs a low level signal. This works only in USB boot mode.

                 

                In the SPI boot mode power up sequence, the INT # output is never changed.

                 

                Therefore, when INT # -RESET # is directly connected, I understand that the RESET # input will be applied at power on, and the USB boot operation will be canceled.

                 

                Is it the specification that INT # outputs during USB boot operation?

                 

                Regards,

                • 5. Re: FX 3 USB boot fault
                  srnt

                  Hello,

                   

                  I was able to see the similar scenario using the Cypress FX3 SuperSpeed Explorer Kit. This is a behavior of the FX3 boot-loader that resides in the internal ROM and hence cannot be modified. So, kindly, modify the hardware to remove the connection of INT# pin to RESET# pin.

                   

                  Best regards,

                  Srinath S

                  • 6. Re: FX 3 USB boot fault
                    user_9155550

                    Hello  Srinath-San,

                     

                    Thank you for response.

                    We will modify hardware connection.

                     

                    Best regards,