1 2 Previous Next 17 Replies Latest reply on Mar 17, 2013 5:29 AM by DaKn_263916

    CY8CKIT-001 DVK

      Does this kit come with an inbuilt buzzer / light intensity monitoring system as is the case with some other kits....




      If no, could you please shed light on how to interface a photodiode/light dependent resistor ?

        • 1. Re: CY8CKIT-001 DVK

          The CY8CKIT-001 DVK does not come with Buzzer or light intensity detector. The kit comes with 3 PSoC 3 family processor module, 4 Expandable ports, UART level shifter, Bunch of Leds for debugging, min USB connector. You can find out more about this kit here, http://www.cypress.com/?rID=37464


          The principle behind Photodiode and LDR is very much the same. In both the devices, with increasing light intensity the resistance of the device decreases(current increases). Hence you can put a series impedance and measure the voltage across the series impedance to detect varying light intensity. 

          • 2. Re: CY8CKIT-001 DVK

             sir, can i interface my light sensor tsl235 directly with CY8CKIT-001 DVK .


            Suggest me how i can interface my tsl235 with this kit

            • 3. Re: CY8CKIT-001 DVK

              Since your frequency input from your tsl235 will range from 10Hz to 300kHz i would suggest to do the following:


              Set up a timer used as a time-base to generate a pulse every second.


              Set up a counter that counts up all incoming pulses from your sensor (must be able to count up to 300,000 which will need 24 Bits width) Generate interrupt at capture and reload on capture


              Set up an ISR connected to the counter's Interrupt output set to rising edge


              Capture with the 1-second pulse the actual count, read captured value within the ISR.






              To fine-tune your system make (measure) y = ax + b to approximate a and b to give you a more exact value.




              Happy coding



              • 4. Re: CY8CKIT-001 DVK

                If you want to make measurements < 1 Hz, which the light sensor is capable


                of, you cannot use a 1 Hz gate for that, use reciprocal counter technique, reference


                material attached.




                Regards, Dana.

                • 5. Re: CY8CKIT-001 DVK

                  Sorry, but datasheet of TSL235 says minimum frequency @ E0  (no light) is 10Hz

                  • 6. Re: CY8CKIT-001 DVK

                    Sorry, worst case it will have an offset of 10 Hz, typically its < 1 Hz -








                    This as well shows this -




                    Regards, Dana.

                    • 7. Re: CY8CKIT-001 DVK

                      Excuse me, please! I took the shown E0 max value for min.





                      • 8. Re: CY8CKIT-001 DVK

                        No excuses needed.




                        The spec you are looking at is a 25 C spec. Furthermore they go out of their


                        way to show in multiple graphs performance below 1 Hz. If you want to accomidate


                        2 - 3 sigmas worth of parts you either make the gate period longer or use reciprocal


                        counting techniques. Or just plan on throwing away dynamic range.




                        Notice this chart does not align with the typ spec either (inconsistant) -








                        Of course either of us do not have a clue about end application, environment, or use, so


                        all we can do is cover as many bases as possible.




                        Of course all this is mute as the part is obsolete.

                        • 9. Re: CY8CKIT-001 DVK

                          One other small point about using a 1 Hz gate.




                          If you are measuring a 10 Hz signal, the meaurement at minimum is +/- 1 count,


                          translate a +/- 10% error in reading.




                          Thats one more reason to use Reciprocal counting techniques at low frequencies/long


                          gate times.




                          Regards, Dana.

                          • 10. Re: CY8CKIT-001 DVK

                             Bob Marlowe : actually my work is to detect light intensity of different laser and measure its frequency and develop a device which is very sensitive. so i m using TSL235 converter for my work. You replied to select timer and counter block and read captured value within the ISR.


                            m not getting it.


                            can u please send me demo of how to select all these blocks .

                            • 11. Re: CY8CKIT-001 DVK

                              Showing the pricipals...





                              • 12. Re: CY8CKIT-001 DVK

                                 Bob: i need to do it on PSoC designer. 


                                send me demo for designer regarding my work.

                                • 13. Re: CY8CKIT-001 DVK

                                  You are here in PSoC3 forum, that's the reason why you got my example for Creator 2.2.


                                  I would suggest, since my example is not a complete project, get a feeling how it is thoght it should work and make it anew for a PSoC 1 chip, although I think that with your performance and precision wanted (and your thoughts to use an analog sensor instead) it could be advisable to insert the PSoC5 processor-module instead. And: if you do not own an ICE-Cube (In-Circuit-Emulator) it will be a bit tough job to debug your project with a PSoC1.





                                  • 14. Re: CY8CKIT-001 DVK

                                    In this thread is a solution, ap note, to solve problem.








                                    Regards, Dana.

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