Translation - Japanese: CY8CKIT-050 DVKでのPSoC®5LPのP0 およびP0 ピンの使用 - KBA210691 - Community Translated (JA)
When I use pins from Port 0 (particularly P0 and P0) in my application, I see that the project does not work as expected. Are there any application-specific issue with these pins?
As you can see the jumpers at J43 and J44 in your DVK connect capacitances from P0 and P0 to ground. These jumpers are by default connected in the DVK. These capacitances are the bypass capacitors used for SAR ADC. Therefore, if you are not using these bypass capacitors, you should remove the jumpers. Now your application should work.
For example: If a DAC output of high frequency is routed to one of these pins, the capacitors act as filter and at the output no signal is observed. If the capacitor is removed then the desired signal should be observed.