F20-uSD Pin Assignments

I am using an F20-uSD module with firmware version 0.5.0. I could not find a document explaining the purposes of the module’s terminals. After consulting the schematic, I determined that the terminal labeled + is for +3.3V Vcc, the terminal labeled - is Gnd, the terminal labeled R is reset (I use a button to pull it to Gnd to reset the F20), the terminal labeled SO is Serial Out, and the terminal labeled SI is Serial In.

I also know that grounding the terminal labeled F3 during a reset starts the bootloader.

I have not determined what the purposes are for the terminals labeled F1, F2, F4, F5, and B0. Is there a document somewhere that tells me about these additional terminals and how I can utilize them? I see that B0 stands for BOOT0 but I have no idea what its function is.

I won’t even speculate about the purposes of the pads labeled PF0 and PF1.

I have exercised most of the basic functionality of the F20 and I think it will fit well into my project. Thanks for offering it.


@ ebjoew - Those function pins are reserved for future use. At the moment, they have no use. B0 will always be reserved.

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