You would end up with a very large grey code if you tried to do that. You could solve that by gearing it down (or repeating the code) and count revolutions, but

You would end up with a very large grey code if you tried to do that. You could solve that by gearing it down (or repeating the code) and count revolutions, but more likely these days you'd use something like a hall-effect angle-position sensor [1]. The ones linked will give you an angle with 2^12 bits, or ~0.09° just by rotating a magnet next to the IC. [1] http://www.allegromicro.com/en/Products/Magnetic-Linear-And-Angular-Position-Sensor-ICs/Angular-Position-Sensor-ICs.aspx http://www.allegromicro.com/en/Products/Magnetic-Linear-And-...