Comment by londons_explore

2 years ago

I really want my computer to have a built in cable tester. Just plug both ends of the same cable into two different ports of a computer, and it has a little popup saying "This cable can support charging at this rate and data at that rate, and is fully functional". Or "This cable has 1 bad pin, and that may affect video/audio/charging/whatever functionality"

Ideally, the computer would test every pin in the cable, and also test the resistance/voltage drop of the cable to detect thinner-than-spec conductors.

I'm pretty sure USB-C hardware in a typical laptop can already do most of this, if only the firmware added support for such testing.

It's really strange that even getting a separate testing device is really hard. There are some that test pins and some that can read the emarker, but none affordable that can do both.

> I really want my computer to have a built in cable tester. Just plug both ends of the same cable into two different ports of a computer … If you have a Mac you might be able to try the Blackmagic Disk Speed Test app. It would require you to also have a drive that* can handle the read/write speeds of the cable you are testing… but you’ll only get accurate numbers if your drive can handle read/write that’s above what the cable can handle. Hopefully someone else knows of a better way.

  • If the computer could test on a loop like the parent comment suggested, every single machine built in the last decade has enough memory bandwidth to test >40Gbps. No need to write to disk.

Mikrotik routers have something like this for Ethernet cables. They can detect how far down a cable break is and on what twisted pair. (They don't test cable bandwidth though.)