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Troubleshooting PCBs

Well, after a night of struggling with the usb ports on my #68keys.io keyboard build I finally figured out the cause of the problem!

The problem: Whenever I plugged the keyboard in to my PC, the PC instantly shutdown :( At first I thought I had connected up the wires wrong. This design calls for a USB mini socket to be soldered on to the PCB, then some wires from test points out to the micro USB socket on the Arduino Pro Micro board that sits on 0.1" headers. It's a bit janky, but the easiest way to be able to have an Arudino on the board with only through hole components. But even after removing that set of jumper wires, no bueno, PC still shutdown.

Next I got one of the PCBs that I've not even put the matrix diodes into and soldered the socket on, same problem. And after a day at work thinking about it, I thought up a solution: The USB socket is on backwards, as that would put the positive pin where ground should be, which is connected to the socket's ground by the ground flood for the metal shell connection.

So, put in a socket on the other side of an empty board: No more shutdown, yay!

Put in a socket on a populated board, still no shutdown. Wire up the arduino's micro USB again, and everything is how it should be!

On further reading, the errata for this version of the board says that the printing for the USB socket is on the wrong side....

More careful attention needs to be paid to the design's I'm using, including the errata!

BGA soldering is probably a bit much for the home shop, but I have had success with previous arduino in the 40 pin square versions using the drag soldering method.

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