I have an OLinuXimo-A20-LIME2 card PC. I would like to use GPIO but I don't understand how could I physically connect them. In the manual, all GPIO are listed. I know with one to use, but male pins on the card are to thin for standard jumper wires (https://www.olimex.com/Products/Breadboarding/JUMPER-WIRES/JW-200x40-FM/). I can solder it, it's to thin...
There are a few options:
1) You can use the LIME2-SHIELD:
https://www.olimex.com/Products/OLinuXino/A20/LIME2-SHIELD/open-source-hardware
2) You can get one or more A20-OLinuXino-LIME2-UEXT adapter(s) - this adapts 0.05" LIME pins of the GPIO/LCD connectors to breadboard-friendly 0.1" step connectors. Notice that it comes WITHOUT CABLES!!!
https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-LIME2-UEXT/open-source-hardware
Cables:
https://www.olimex.com/Products/Components/Cables/Ribbon/CABLE-40-40-10CM/
https://www.olimex.com/Products/Components/Cables/Ribbon/CABLE-IDC40-15cm/
3) You can purchase matching female connectors FEMALE-YAV36P-2x20. This will still require soldering at the female connectors but your board will be safe:
https://www.olimex.com/Products/Components/Connectors/FEMALE-YAV36P-2x20/