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    Python script emulating vantage protocol

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    engolling
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    Weather Station: WH3080 + Custom Station
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    Python script emulating vantage protocol

    Post by engolling » Thu 12 Jan 2017 8:44 pm

    Hello,

    I want to write a python script beeing able to send data from my self built prototype weather station to cumulus (picture in attachment).
    I am measuring the following data:
    1. Temperature 2m
    2. Temperature 2m in the Sun
    3. 7 Temperatures from 1m to -1m over/under ground
    4. Pressure
    5. Humidity
    6. Wind speed
    7. Wind direction
    8. UV radiation
    9. global radiation
    10. Illuminance
    11. Percipation
    12. Snow depth
    13. Leaf wetness
    14. Particle concentration
    If someone is interested in, I can post more details of the station, if I find some time.

    Since the Vantage protocol is well documented I consider to implement this. After reading the documentation I saw that the LOOP packet is able to transmit data of more extra sensors then the LOOP2 packet. Is that right?

    Has anyone a idea if there is a more apropriate and well documented protocol especially I have a lot of possible data to transmit.

    When implementing the LOOP packet, can anyone tell me which data is not taken into account by cumulus like the alarms or the forecast icons.
    I assume there is no need to implement the HILOW packed, because cumulus calculates all the data by itself.
    When the script is working, I will provide it here, maybe someone can use it, too.

    Hoping for a lot of feedback.

    Stefan
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    steve
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    Re: Python script emulating vantage protocol

    Post by steve » Thu 12 Jan 2017 9:02 pm

    I can't tell you exactly which items from the LOOP packet that Cumulus 1 uses, because it doesn't handle the LOOP packets itself, the Davis DLL does it.

    I could tell you exactly what items from the LOOP packet Cumulus MX uses, but I would have to extract the information into a form that I could give to you, and that is somewhat time consuming, and complicated by the fact that it extracts some values from the packets that it doesn't currently use; I would have to check each one to see if it actually uses it.

    You're right that Cumulus (1 and MX) doesn't use the high/low data or anything else other than LOOP packets and archive packets. It should be reasonably obvious which items from those packets it uses given the data that it makes available. It uses the annual rain total as the increasing counter from which it calculates all the other rain totals.
    Steve

    prodata
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    Re: Python script emulating vantage protocol

    Post by prodata » Fri 13 Jan 2017 9:18 am

    Remember that in addition to populating the LOOP/LOOP2 packets, any emulator software also presumably needs to emulate the API by which data packets are normally requested from the WL logger. This isn't necessarily difficult but would be essential if any analysis software is going to think that your emulator is a logger.

    LOOP caters for all the sensors that can be attached to a wireless VP2 station. LOOP2 only services a subset of those sensors but does include more derived values such as 2min wind speed and several other analogous values that are normally calculated by the VP2 console from the raw sensor readings. Conversely, LOOP2 does not include any readings from supplementary sensors, eg 6345 transmitters.
    John Dann
    Prodata Weather Systems
    Littleport, East Cambs, UK
    http://www.weatherstations.co.uk

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    laulau
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    Re: Python script emulating vantage protocol

    Post by laulau » Fri 13 Jan 2017 10:18 am

    Hi,
    This project is compatible with Cumulus by emulating a Davis VP :

    http://sandaysoft.com/forum/viewtopic.php?f=16&t=12083
    Laurent

    Image

    engolling
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    Re: Python script emulating vantage protocol

    Post by engolling » Sat 14 Jan 2017 8:40 am

    Hello,

    thank you for all your replys.

    @steve It's no problem, if it's very time consuming because I can write default data in fields that I do not use. Just thought maybe there is some overview I did not find.

    I have already seen the weather duino project but I could not download the software without registration, but I will have a look at it.

    I will keep you updated if there are news.

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    ConligWX
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    Re: Python script emulating vantage protocol

    Post by ConligWX » Sat 14 Jan 2017 1:34 pm

    Not sure if this is of any use.

    Have you tried looking at http://www.weewx.com/. the weather station software is written python.
    Regards Simon

    https://www.conligwx.org - @conligwx
    Davis Vantage Pro2 Plus + DFARS - Meteobrige Nano SD + Saratoga Templates

    engolling
    Posts: 8
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    Re: Python script emulating vantage protocol

    Post by engolling » Sun 12 Feb 2017 10:08 pm

    After a lot of considerations a skipped programming the python script and I'm going to implement the emulation into the arduino µC like the WeatherDuino project does.
    Thank you for all your feedback.

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