6 Replies Latest reply on Sep 16, 2019 6:55 PM by MoTa_728816

    ICSP problem new board



      I designed my own board using a CY8C5287AXI-LP095 100 pin TQFP but am having problems using the programmer from an 059 kit to program it with a hello world type program. It doesnt respond.

      I discovered  (after powering it !!!) that I had left off the 5V connection to VDDA. Is this likely to cause irreparable damage?

      Also pins 57-62 are marked as NC. Are they electrically isolated internally, or used for internal testing, as I used some of them to extend my ground plane under the chip, and could this explain my problems.

      I'm not aware of any other deliberate mistakes Ive made, but does anybody have any further ideas why it might not program?


        • 1. Re: ICSP problem new board

          Should have said,

          This is error I get when trying to program within Creator.


          And cant find any device in Programmer



          • 2. Re: ICSP problem new board

            Dear Steve-san,


            It would be easier for others (including me) to consider the source of the problem,

            if you can provide us the schematic around the device and around SWD connector.


            From your question and what I think (as usual, I may be wrong),

            (1) The connection between 5V VDD and KitProg's VTARGET won't be a  problem,

                but may be  you had better provide only one power at a time.


            (2) Is your KitProg detached from the CY8CKIT-059 or is it still attached?

                 If the KitProg is still attached with the CY8CKIT-059,

                 you need to detach it from the board to make KitProg work with other boards.


            (3) In general "NC" means "No Connect" and some pins may need to be free to change their level,

                 so connecting them to GND may cause problems.

                 But I don't think that this is directory connected to the "Unprogrammable" issue.


            Best Regards,


            Motoo Tanaka

            1 of 1 people found this helpful
            • 3. Re: ICSP problem new board

              Konnichi wa Tanaka san,


              Hazukashi.  Entirely my bad. I double double checked and discovered that I had connected VCCA to 5v, which I suspect has deep fried the internal regulator. New chip on order, and sharpened my scalpel to correct. Will post if that was problem in a few days.



              • 4. Re: ICSP problem new board

                Hello Steve.

                In Programmer 3.28, you'll find CY8C5287AXI-LP095:

                Device Family: CY8C5xxxLP

                Device: CY8C5287AXI-LP095


                As Motoo suggested, you need to detach Kitprog from KIT-059.

                Also, keep SWD wires from Kitprog to your target device very short.  5cm works very well.  Beyond 10cm, people have had problems.


                And, to stop Kitprog from entering its own bootloader (slow flashing LED on Kitprog pcb), place a pull-up resistor on Kitprog XRES signal.  Anything from 10k to 56k works.  You may or may not need this.

                The error that your showed, it typical of a PSoC that's not coming out of reset state.  In your case, it may be a blown chip.  I'd still attempt to program it with some of our suggestions.  You might be pleasantly surprised (or not).


                Cypress uses the term, Do Not Use (DNU), for pins that should not be connected to other circuitry.  They use No Connect (NC) for pins that have no internal connection.  This is found at the end of the datasheet under Acronyms.  For example, CY8C5266AXI-LP132 has DNU for certain pins (pinout footnotes for 100-TQFP) because it does not have USB on those pins, they must be left floating.


                So, you should be okay with NC pin ground connections.  Unless Cypress tells us otherwise.


                Good luck with the new chip.


                2 of 2 people found this helpful
                • 5. Re: ICSP problem new board

                  Thanks Bill,

                  Comments noted.

                  Yes I did detach KitProg, but Im fairly sure Ive deep fried the chi, there's 24 Ohm across 5v and Ground!!!, and its killing KitProg supply..


                  Your comments on keeping wires short and a pullup on reset very helpful, as are notes on NC.


                  Nice to get such speedy and helpful responses from the community for what is entirely my own stupidity!!


                  Thanks guys , next time i'll triple check before posting.



                  • 6. Re: ICSP problem new board

                    Dear Steve-san,


                    You have very nice Japanese vocabulary!


                    I double checked the datasheet, if it was VDD or VDDA you were OK,

                    but if it was VCCA, yes, the device must have been well done.


                    Meantime 24 Ohm between 5V and GND causes 208mA, which does not sound good.

                    But in my experience the USB protection circuit usually cut off the power before the device is cooked well,

                    so there may be a  chance that KitProg is still alive.

                    (Try connecting only the KitProg to see if it will be detected by Windows)


                    Anyway, I hope that you will have better result in your next trial.

                    Good Luck!


                    Best Regards,


                    Motoo Tanaka