Encoder rate noise

[Joe Ross]

Originally Posted by compwiztobe

What happens if you switch 4x decoding to 1x? You lose direction sensitivity, but it only counts one edge of one channel, instead of both, so it may be able to keep up better.

Switching to 1x decoding does not lose direction sensitivity. It still uses the B channel for direction, but only 1 transition of the A channel.

1x decoding helps reduce noise beyond just reducing counts to within the limit of the FPGA. It also allows additional digital samples between each count, effectively acting like averaging 4 samples at 4x. It also ignores manufacturing tolerances between the different signals, like Ether mentioned. For the S4 encoder, B lags A by 90 degress +/- 60 degrees (max).