Ever wonder if your USB C cable is USB2 or USB3? Do you have some charge-only cables hiding in a box just waiting for the right moment to spoil your project plans?! Fear no more!
I’ve made a simple board to test most of the things!
USB Cable Tester v2.0 - Front
USB Cable Tester v2.0 - Back
USB Cable Tester v2.0 - Side
(This post is derived from my original twitter thread about it.)
How does it work?
Connect your cable to both sides and the signal LEDs will light up if they are connected. Here’s an example of a USB2 cable and a thunderbolt 3 cable.
Testing a USB-C 2.0 Cable
Testing a Thunderbolt 3 Cable
Want to test a USB A to C cable? How about a USB A to Micro B? USB C to B? Mini B? You’ve got it!
Testing a USB A to C Cable
Testing a USB C to B Cable
Testing a USB A to Micro B Cable
Here’s what a the dreaded charge-only cables look like. I had to make my own since I had previously banished them from my lab! (These are the real reason I made this)
Testing a Charge-only Cable
Homemade Charge-only Cable
But….What if my cable is too short!? We have that covered too 😂
Testing a short USB 4 Cable
Testing a short USB 4 Cable (Part 2)
How can I get one?!
Like most of my projects, the files are available on the github repo under an open hardware license.
If you want to make your own, I have instructions on ordering your own from JLCPCB here: https://github.com/alvarop/usb_c_cable_tester/blob/main/ORDERING.md
What do all the signals mean?!
I still need to make a nice diagram explaining what you should see for each type of cable. Until then, here’s the short version:
All the signals from the USB A connector will show up on the right column of LED’s (A1-A12). The “B” side is only used for the USB-C port on the left. The D+/D- signals are the “USB 2.0” data lines. USB-3 will have TX1+/- and RX2+/-.
Every USB-C cable should have either CC1 or CC2 (which will change if you rotate the cable).
Updates!
You can follow project updates on github. I’ve released a new version with some fixes, but, unfortunately, it still has some issues.