Arbitrary Quadrature Encoder

[nuttle]

Looks nice -- have fun!

BTW, I think you could connect up to 8 of the encoder chips I mentioned over SPI, using something like a 74LS138 (and even more using a similar scheme with more/different parts to select which chip to enable). The datasheet for the encoder chip shows this in Fig 15. You'd hook the SS* line from each chip to one of the outputs from the 74LS138, and inputs to the 74LS138 would be three digital output lines, plus the original chip select line from the digital side car. You would use the three digital output lines to choose which encoder chip to interact with, one at a time. Other than this, the rest of the SPI usage should be unchanged. If someone out there is looking to try something like this, I just wanted to follow up.

Good luck with the project, it will be very useful I'm sure and to others as well. Thanks for sharing!