Other RP2040 boards • Re: RP2354 RUN and QSPI_SS pins strange behaviour

e) The Reset does not work. I measured the voltage at the RUN pin using PCBite probes, measuring the correct voltages 3.28V (no reset) and 0V (when RESET button pressed).

Something is wrong here. Maybe soldering problem on the RUN pin?

f) I connected the QSPI_SS pin via 10kOhm to 3.3V and via 1kOhm and BOOT button to GND. When I press the BOOT button, I expect a voltage around 0.3V, but I measure 3.14V when the BOOT button is pressed and 3.28V when the BOOT button is not pressed. The button works fine, I measured 0V when pressed.

This is normal. The QSPI_SS pin is only floating for a short while after reset: once the bootrom has started accessing the flash, the QSPI_SS is driven actively by the RP2350 and you would not expect attaching a 1K resistor to have much effect.

You need to debug your reset problem before you can look further at this (but it's quite likely working fine).

Statistics: Posted by arg001 — Fri Jan 30, 2026 7:47 pm

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