The insanity of USB and USB-C specifications are a headache. Most of us have probably used trial-and-error to find the "right" cable to charge a device or do a firmware update. If you have a collection of mystery cables, this gadget may be worth the investment. It helps you sort through and identify what your cables do and provides a quick sanity check whether a cable is good or bad.
Treedix makes an inexpensive ($16) version that simply shows a glowing LED for each pin connection which may be good enough for occasional use. The deluxe model has a built-in display and gives you easy to read results plus e-marker and resistance info.
