Apart from understanding the Arduino's code language, one of the most confusing parts about the platform ... there are two options: a Nano and a Micro. They look like the same board to the ...

[mircemk] shows how to create a simple non-contact proximity sensor using little more than an Arduino Nano board, and a convenient software library intended to measure the value of capacitors.

Although a “CommsLink” module providing an RS-232 port was available back in the day, it’s become hard to find, inspiring [James] to design a completely new module based on an Arduino Nano.