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baol / waving-z

:ocean: :wave: Waving-Z, an ITU G.9959 (de)modulator. Started as a fork of andersesbensen/rtl-zwave it evolved to a state in which not a single line of code is shared anymore :)
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Values doubled #8

Open scaarup opened 3 years ago

scaarup commented 3 years ago

I am using this project with my rtl dongle and sometimes experiencing values which are doubled. This here payload is captured with a z-wave sniffer from Jon Suphammer (not related to this project):

000210 2 813 0C 0D4720202021030020102011030F031703280318032F03300893098C083D011D01212F0056F03361 And this one with "rtl_sdr -f 868420000 -s 2000000 -g 25 - | /waving-z/build/wave-in -u": 000420 5 026 18 1a8e40404042060040204022061e062e06500630065e066011261318107a023a02425e00ade066c3 It is the same message from the same radiator thermostat, but captured from both sniffers. From the top payload I can read out 083D which becomes decimal 2109. From the rtl payload I can see 107a which becomes decimal 4218 - exactly double. What is going on?

baol commented 2 years ago

Doubling can be the result of a shift left by 1. A misalignment with the signal while reading is my guess. Which one is correct?

scaarup commented 2 years ago

The fist one is correct - decimal 2109. It is a reading of 21.09 degrees celcius from the thermostat.