A continuity tester, as found on most multimeters today, ... The output of the comparator toggles when the resistance between the other input and ground is either higher or lower than 51 ohms.

For those interested in building this handy tester, [David] has shared the Eagle CAD files as well as the ATtiny85 code on his Github repository or you could just order out some boards from OSHpark.

The black & white continuity test attempts to use a minimal set of test conditions to detect all potential shorts between two or more pins on a package. In conventional pin-to-pin continuity test, the ...