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How to tell what from where on ribboncables?

I'm a bit stuck with a thing, the ribbon cables, I have no idea how to read them.


the only thing I know now is that the red cable is the first one, but I have no idea which pin it is associated with, or how to read the successing cables in the ribbon after the first one.


basicly, which cable goes to which pin when you are working with ribbon cables? :) 

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Yeah, I ran into that same problem. I just used a multimeter in 'continuity tester' or 'resistance' mode to figure out how the pins were arranged, and which pins were connected to which cables. They follow an orderly pattern, so once you check 2 or 3, you know how the rest of them work. If it's a standard computer ribbon cable with two rows of pins on the connector, then they're arranged vertically in pairs, like this:

1   3   5   7   ...
2   4   6   8   ...

So one row is all odd numbers, and the other row is all even numbers. I actually can't remember if 1 is on top of 2, or if 1 is on the bottom and 2 is on top of that. You should check for yourself with a multimeter. But that's basically how it works, at least for those pins that come out of computers for hard drives and floppy drives. BTW, one extra hint, if you're using a cable for a hard drive, is that pin 19 is missing on those cables. So if you find the pin that's missing, you know that that's the row with the odd numbers.


Thanks!, I don't have a multimeter though, but I'll find it out using the pata-cable trick.

If you don't have a multimeter, u can find with a wire, a led and a battery..


just connect the wire to the let (use a resistence if the batery is to high to don't burn the led (330 Ohm is enuf)) and atach the wire to one side of the cable.. then go to the other side, and connect the battery with the pins until the led become on.

 Thats a simply way to check if is the wire that you are looking for.

Good luck

the mapping of the ribbon cables' pins is in the documentation that comes with the PICAXE 28X1 starter kit.