6 Replies Latest reply on Jan 11, 2018 3:47 AM by user_474444345

    Non-Connection of VSYS

    user_474444345

      Hello,

       

      In CYPD3125-40LXQI, when VBUS is directly ant unfortunately provide from internal system power source, can we open VSYS pin?

       

      In that case, when we try to debug our software through SWD, do we need any especial sequence which is difference in a case of providing VSYS from VTARG?

       

      Best regards,

        • 1. Re: Non-Connection of VSYS
          lisz

          Hi Takeshi-san,

           

          1. You can open VSYS pin. The firmware default setting is, CCG3 get power from VSYS first, if VSYS is not powered on, VBUS is the second power source for CCG3.

          2. The power sequence of VTARG shall be follow SWD programming SPEC. And SWD programming SPEC have difference power setup.

           

          Best Regards,

          Lisa

          • 2. Re: Non-Connection of VSYS
            user_474444345

            Hello Lisa-san,

             

            Thank you for your prompt replay.

             

            > 2. The power sequence of VTARG shall be follow SWD programming SPEC. And SWD programming SPEC have difference power setup.

             

            This mean that I cannot debug FW from SWD programmer or debugger such as Miniorog3 if I keep to open VSYS?

             

            Best regards,

            Takeshi

            • 3. Re: Non-Connection of VSYS
              lisz

              Hi Takeshi,

               

              You still can debug FW from SWD programmer, since the VTAG will power on VSYS if you are connected VTAG to VSYS.

               

              Best Regards,

              Lisa

              • 4. Re: Non-Connection of VSYS
                user_474444345

                Hello Lisa-san,

                 

                Yes, if VTARG power on VSYS, We can debug FW from SWD programmer.

                 

                if VBUS is provided 5v power, VSYS can keep to opn. so we will open VSYS.

                By the way, if VBUS connect to 5 volt source which is always provided by user system and VSYS, however, does not provide from any source, Can we debug FW?

                Or, Does VTARG have to connect VSYS?

                ________

                      VBUS |-- v5

                      VSYS |-- open

                --------------

                 

                Best regards,

                • 5. Re: Non-Connection of VSYS
                  lisz

                  Hi Takeshi-san,

                   

                  As per my test results, the SWD programming cannot complete if supply VBUS with 5V only. Please kindly connect VTARG of MiniProg3 to VSYS.

                   

                  Best Regards,

                  Lisa

                  • 6. Re: Non-Connection of VSYS
                    user_474444345

                    Hello Lisa,

                     

                    On CY4531, I also tried to check.

                     

                    J3 1-open, 2-GND, 3-VBUS

                    J4 1-open, 2-3 connected

                     

                    I can download my program from programmer.

                    It is succeed.

                     

                    What is my problem to check it?

                     

                    Best regards,