It took ALL day. But here it is! Works great. I had NO idea how electrically NOISY a CNC machine is but everytime I mounted the tach it quit working. I finally changed over the wires to shielded CAT 6 and grounded the shielding to the ground bus. That reduced the noise to the point of functionality. The new code is capable of at least 25,000 rpms - I don’t have anything faster apparently. It is also attached.CNC_Tachometer_FreqMeasureLib_v4.ino (3.0 KB)
SmallerTachVid.mp4 (8.8 MB)