RP2040 vband CW key adapter

Ham Radio Solutions sells a $30 device that lets you connect your CW key to your phone or computer. It essentially acts as a keyboard that sends a left control or right control based on which side of a paddle you connect to. I wanted to be able to use my CW key with my Android phone for practicing on the go, but I didn&rsquo;t really want to spend $30 to do that. I thought that I could build an…