2 Replies Latest reply on Feb 7, 2020 8:59 AM by AmSh_3068021

    Mismatch in Data during use

    AmSh_3068021

      Hello,

       

      We have a LED board which are running using CY7C64215 chip on it. After programming the part it runs fine while testing the unit.

       

      But when we use it for actual application then in few boards some data gets change. Please see below example.

       

      Data read from the board after programming:

                    | 3fc0: 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ff

       

      Field return board data:

                    | 3fc0: 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

                    | 3ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fe

       

      In field return board half of the functionality works fine, for example LEDs on the board works fine but not USB detection.

      After reprogramming chip it starts to work fine.

       

      So I am trying to understand that how few bytes gets change in the memory of controller without programming?

       

      Please review and advise.

       

      Thank you in advance

        • 1. Re: Mismatch in Data during use
          HemanthR_06

          Hi,

           

          Have you tested the board multiple times before it is used in the field? If yes, what is your observation?

          What is the environment where the board is used? What is the end application?

          Howmany boards behave like this. Out of howmany? Is it a custom board?

           

          Regards,

          Hemanth

          • 2. Re: Mismatch in Data during use
            AmSh_3068021

            Hello Hemanth,

             

            Thank you for your reply.

             

            Boards are tested once or twice before it goes to the field. We shipped boards to customer and receive 10 to 20 pcs under an RMA for the same issue. This time we received few boards which were fixed recently so need to identify the cause.

             

            I am not aware about end user application.

             

            it is a custom board which has MCU CY7C64215 to drive multiple LED driver chips. And also it talks to other devices like computer using USB.

             

            Please let me know if you need more inputs.

             

            Thank you.

             

            Regards,

            Aman Shah