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    cristi

    @cristi

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    Best posts made by cristi

    • RE: 💬 Air Humidity Sensor - DHT

      2 issues I see with the example:
      a) I'm not a native english speaker, but to me, on top of the page, "sampling rate" of "2 times/sec" for dht-22 is wrong. From code and pdf you can see that you can't ask for data faster than at 2 seconds.
      As such, I would change the top of the page to read either "0.5 times/sec" or "1 time at 2 seconds".

      b) use of SENSOR_TEMP_OFFSET is wrong. Because depending on how the controller wants this sensor's data (Celsius | Fahrenheit), the offset will be different. If you happen to change the metric system value in the controller and ask for the data (after sensor restart let's say), you'll get a different value than expected).
      I would do:

        • add to the comment for SENSOR_TEMP_OFFSET that we're talking about a Celsius offset
        • and move the statement "temperature += SENSOR_TEMP_OFFSET;" before the conversion to Fahrenheit.

      Regards.

      posted in Announcements
      cristi
      cristi

    Latest posts made by cristi

    • RE: 💬 Air Humidity Sensor - DHT

      @mfalkvidd Indeed, I see that 10 seconds in pdf, but it looks strange. I'd have to re-read to see if I can get what it is supposed to be for.
      But, meanwhile, in the same pdf, you get this note (chapter 6): "Note: Sampling period at intervals should be no less than 1 second.". Also, DHT library is using 1second sampling period.

      posted in Announcements
      cristi
      cristi
    • RE: 💬 Air Humidity Sensor - DHT

      @mfalkvidd

      • there's a typo in the table for DHT-11: it should be '1s per sample' instead of '10s per sample'
      • I created a pull request
      posted in Announcements
      cristi
      cristi
    • RE: 💬 Air Humidity Sensor - DHT

      2 issues I see with the example:
      a) I'm not a native english speaker, but to me, on top of the page, "sampling rate" of "2 times/sec" for dht-22 is wrong. From code and pdf you can see that you can't ask for data faster than at 2 seconds.
      As such, I would change the top of the page to read either "0.5 times/sec" or "1 time at 2 seconds".

      b) use of SENSOR_TEMP_OFFSET is wrong. Because depending on how the controller wants this sensor's data (Celsius | Fahrenheit), the offset will be different. If you happen to change the metric system value in the controller and ask for the data (after sensor restart let's say), you'll get a different value than expected).
      I would do:

        • add to the comment for SENSOR_TEMP_OFFSET that we're talking about a Celsius offset
        • and move the statement "temperature += SENSOR_TEMP_OFFSET;" before the conversion to Fahrenheit.

      Regards.

      posted in Announcements
      cristi
      cristi