Difference between revisions of "Protocol decoder:Graycode"

From sigrok
Jump to navigation Jump to search
(Created page with "{{Infobox protocol decoder | id = graycode | name = graycode | description = Gray Code and Rotary Encoder | status = ?? | license...")
 
Line 11: Line 11:
| probes          = —
| probes          = —
| optional_probes = D0-D7
| optional_probes = D0-D7
| options        = numchannels, pulses, avg_period
| options        = numchannels, edges, avg_period
}}
}}


Line 18: Line 18:
== Parameters ==
== 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.
'''edges''': Rotary encoders are usually labeled as having N ''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 ''4N 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.
'''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.

Revision as of 20:03, 18 September 2017

graycode
Pd graycode.png
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, edges, 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

edges: Rotary encoders are usually labeled as having N 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 4N 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.

Resources