Luckily for Dustin’s iTrackMine habit, i3’s electronics lab had a set of 10p10c crimpers and a box of connectors (and a resourceful mentor geek), waiting to solve just such a problem. After building a little 10p10c breakout cable and a USB breakout cable, some breadboard jumper wires made it relatively straightforward to investigate every permutation until the device enumerated. (Note that ‘straightforward’ does not equate to ‘quick’.)
For the purpose of saving some hapless future scanner technician some time, the pinout is as follows:
USB pin number | function | color | 10p10c pin number |
1 | +5 (Vcc) | Red | 7 |
2 | D- | White | 10 |
3 | D+ | Green | 2 |
4 | Gnd | Black | 4 |
Two construction tips:
First, it’s difficult to position the wires in a modular connector if you’re not using every position. Stuffing the unused ones with little stubs of wire made it easy to guide the relevant wires into position.
Second, modular connectors can be reinforced by flooding the back with hot-melt glue. (This works very well on cat-5 patch cords.) Since this build used a flexible, thin USB cable in a giant 10p10c connector, the glue is the only reason it didn’t fall right out.