Hello Cypress community,
I am working on a prototype of a product based on the PSoC 6, currently using a Pioneer board for prototyping. The board has been very reliable until last week, when the MCU became unresponsive without an apparent cause. It was powered from a UPS-grade lead-acid battery via the J9 header, turned on and off with a mechanical switch, with two rectifier diodes in series to take the maximum possible voltage down to below 12V. The PSoC itself was in a testing regime, analysing analog and digital signals from a signal generator at no more than 3.3V at its inputs, with little EM noise in the setup. BLE was used to output test results to an Android app, and the onboard RGB LED provided connection status information. At one point after a power cycle, the LED didn't light up red like it should at startup, and the device was not discoverable via BLE, although the KitProg LEDs lit up as expected. Switching SW5 to 1.8V brought back the BLE advertising while the RGB LED didn't light up (which is explained as excepted behaviour in the Pioneer board guide), but any measurements taken gave wrong results, which I attribute to the reference voltage being lower than expected. The 3.3V pin on the Arduino-compatible header was measured to output a voltage around 3.3V. Programming the chip over USB was also only possible with SW5 at 1.8V. When 3.3V was used, PSoC Creator was able to find a KitProg over USB, but it displayed an error when trying to acquire port. At the same time, ADC voltage was shown in the programming dialog to be around 3.3V. All other switches on the Pioneer board were left in their default positions since the start of this project. Also, identical symptoms showed up on a replacement board in the same circuit after a few days of working flawlessly.
As the only reason for this failure I could make out appears to be power-related, and input voltage to the board was kept within specified limits, I need to ask the community - am I missing something here? Has anybody experienced similar issues? What could be the cause, and can the boards be repaired, or should they be replaced?
I will be happy to provide any further details that might help solve this problem. Also, if there is any diagnostic tool or test firmware to use on the Pioneer board, I'm looking forward to give them a try.