I designed a PCB that uses the RP2040 microcontroller. I just received it and wanted to power it up and put my code onto it, but it doesn't seem to work fine. I am struggling to find out what could be the reason, since there are so many possibilities. Here's the schematic and a screenshot from KiCad with the PCB:
(I used a power plane on the top layer to get the power everywhere, I removed it here so it is clear how the traces were made. This is my first design, so any advices regarding the layout would also be greatly appreciated.)
It seems to be powered just fine, I verified it with a multimeter and components are getting power, but when I try to go into BOOTSEL mode (by connecting
J4 to ground and restarting), it doesn't show up on my PC as a USB mass storage device. I have a special connector with USB- and USB+ pins exposed (
J4), which I connect to my PC through a breakout board with an USB-A plug (like this one: https://www.pololu.com/product/2585). I think maybe this is the part where I got something wrong - I think the microcontroller is working fine, but the USB connection is not working properly.
Any help would be greatly appreciated.