OpenDRO Part 0

OpenDRO is a project of mine to build an opensource DRO. Apologies for audio - filmed on potato cam (phone), and I think my hand was near the mic. This is a bench test of a single arduino + seven segment display to see if I am reading the 5 micron encoders correctly. Looks like I've got interrupt handling and direct port manipulation working! The native Arduino digitalRead() calls are too slow, and the counter couldn't keep up, even with moving the carriage slowly. Next steps are fairly trivial at this point: multiply the number (a counter of ticks or pulses from the scales) by 0.005 to get millimetres, and add a button to multiply the counter by 0.0001969 to get inches. Each tick in the scale is about 2 two tenths. A second button to zero the reading. After that, get a project box, and my DRO will be the equivalent of the 1980s dinosaur units.