Protocol decoder:graycode
Name | graycode |
---|---|
Description | Gray Code and Rotary Encoder |
Status | ?? |
License | GPLv2+ |
Source code | decoders/?? |
Input | logic |
Output | graycode |
Probes | — |
Optional probes | D0-D7 |
Options | numchannels, pulses, avg_period |
The graycode protocol decoder can decode Gray Codes up to 8 data lines (but easily generalizes). One popular special case is the Rotary Encoder, which has two lines, A and B. The decoder will report phase, counting direction, absolute count, as well as timing information. Sorry for that mislabeling.
Parameters
pulses: Rotary encoders are usually labeled as having X pulses per turn. A pulse consists of rising and falling edge and you have two lines that are phase-shifted by 90° to one another. This allows to extract 4X edges per turn. the pulses parameter should be equal to the number of edges per turn.
numchannels: due to a current bug in Pulseview, assigned optional probes aren't reported correctly, so you'll have to select the number of channels manually.