gregstachowski/heavy-weather-file-read

Read history.dat binary files from Heavy Weather weatherstation

heavy-weather-file-read

Read history.dat binary files from Heavy Weather weatherstation

Data file format:

Records are 36 bytes long. Data is written in the same units specified in Setup within Heavy Weather, in a mixture of 4-byte floats and integers. Dewpoint and windchill are not stored in the binary file, and are calculated on the fly for the text file.

Bytes:

  0 -  3 : These bytes probably specify the units used in the file.
  4 -  7 : Date, unsigned 32-bit long integer, in seconds,
           (probably) from 1.1.190[01].
  8 - 11 : Pressure, 32-bit float.
 12 - 15 : Wind speed, 32-bit float.
 16      : Wind direction, 8-bit integer (unsigned char), compass points
           clockwise from N (0=N, 1=NNE, 2=NE, 3=ENE, ... 14=NW, 15=NNW).
 17 - 19 : Blank (all zeros).
 20 - 23 : Total rainfall, 32-bit float.
 24 - 27 : Indoor temperature, 32-bit float.
 28 - 31 : Outdoor temperature, 32-bit float.
 32      : Indoor humidity, 8-bit unsigned integer.
 33      : Blank (reserved?).
 34      : Outdoor humidity, 8-bit unsigned integer.
 35      : Blank (reserved?).

"No data" markers:

Note: these markers are empirically deduced from the data file and may not be completely correct.

 Wind speed (also affects direction): 00 00 4C 42
 Outdoor temperature: 52 38 A2 42 (= 81.1 deg. C)
 Outdoor humidity: 6E (> 100%)

Copyright (C) G.S.Stachowski, 2003.08.29

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TBDW:

--"no data" markers for all sensors

-- first four bytes - automatic unit interpretation?

-- bugs in temperature, pressure and time code? :

Record 413: Indoor temp i s 23.5, read as 0.0.

Record 3: Date in txt file is sensible (= rec. 2), read as 244.