We use IDC terminated ribbon cables for the PanelOne LCD controller that we use in our Mini Kossel 3D Printer kits. Its a slow process to test these cables by confirming that the LCD, SD card, encoder etc all work so I looked for an IDC ribbon cable tester. I found a few online but they ran to ridiculous prices (~£250+) so decided to make one using an Arduino Mega and some strip board:
As can be seen there has been no time wasted on making it look pretty, in fact it is probably the ugliest circuit I have made, ever, however it works and tests cables!
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| Stripboard IDC cable tester circuit - hot glue used to protect questionable soldering |
The circuit schematic includes the connections for a PanelOne as I had a prototype board that was no longer being used, however any 20x4 LCD screen and push switch would work.
It uses the internal pullup resistors on the arduino pins so no external components are required other than the connecting wires and headers.
I wrote a simple Arduino sketch to check the cable and display the results. It finds open and crossed wires:
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| Arduino Circuit Tester - Start Screen |
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| Arduino Circuit Tester - Open Circuit |
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| Arduino Circuit Tester - Crossed wires (plug on backwards) |
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| Arduino Circuit Tester - Good cable |
The next step will be to make a circuit tester for the 50 way Duet-Duex4 expansion header cables however that would require 100 pins which is more than is available on the Mega.... I2C port expanders here we come! Also I think a PCB will be required as 100 wires on stripboard would take far too long.
As usual its all open hardware and software - available on the Think3dPrint3d Github.
I hope someone finds this useful and I would be interested to see if anyone else tries this!
