After looking through a ton of other forum posts about cable testers, I don't seem to find what I'm looking for.
There is a product that I've used in the past made by Cami Research called "Cable Eye," that, when set up properly, can give you a graphical representation of a cable that you've plugged into the machine.
It allows you to "learn" the cable (plugging in a cable that is known to be correct), and then compare new cables to the initial correct cable pinout, giving you a "Pass/Fail" description. It also shows if pins are mis-wired, or if there are shorts in the cable.
This I'm not sure about. I made a super simple tester with a rotary switch, resisters and LEDs to tell me simply, but I'm trying to make an automated version. Basically a DIY version of the Cami Research product.
From reading through previous posts, if I were to compare the input --> output, I'll need a significant amount of pins, which I believe can be achieved through shift registers for this particular application.
In that case (assuming whoever built/repaired the cable did the other connector properly), I'd get the same result: "Mis-wire on pins A + B" ... so on and so forth.
At least that's how the other software works.
Again, the product I'm looking for exists already, but it's based on windows and the one I use on a regular basis is in a server rack with all of the different connectors on it. I'm looking to make several purpose built versions, for different types of connectors.
The Cable Eye software, that I'm trying to replicate using arduino, is based on windows.
The following question is, using whatever method is most efficient, where do I look to figure out the "compare this new thing to what we know to be correct, and if it's not correct, say what about it is different than the original"
What you’re trying to do is quite possible - using SR or multiplexing strategies.
the hardware will be a significant challenge - the swappable connector heads for different types of cables will need to be rugged, reliable and easy to change - and a lot of point to point connections !
The testing logic is challenging, but not impossible - and should run on almost any processor with enough memory to hold the pin maps and testing algoriypthms.
There are several connectors that are fewer pins, an easy start would be shielded ethernet cables (9 pins on either end). Going up from there is a 6 pair cable (with 18 pins on either side), a 12 pair cable (36 pins per side), 24 pair cable (72 pins per side), and the big one: 48 pair cable (with 144 pins per side).
Are there resources you know of that would point me in the right direction for the pin mapping and testing side of things?
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