Protocol of the Lacrosse WS7000-15 wind sensor

Each frame is 61 bits long. It is composed of:

Example 1
0000000000111001111011010100001100011010100101111010110111011

Example 2
0000000000111001111010000100001100011010101001111011010111001

Example 3
0000000000111001111011010101001100010000100001000110101110011

When extracting data from the 3 examples, we get:
Example 1
1100 1110 1010 0000 1000 1010 0010 1110 0110 1101 

Example 2
1100 1110 0000 0000 1000 1010 0100 1110 1010 1100 

Example 3
1100 1110 1010 0100 1000 0000 0000 0001 0101 1001 

The 1st bit of each word is LSB, so we have to reverse the 4 bits of each word.

The active values of the sensor is coloured in [green] in the following tables:
Example 1
0011 0111 0101 0000 0001 0101 0100 0111 0110 1011 
3 7 5 0 1 5 4 13 6 B 
Check Xor : (3 ^ 7 ^ 5 ^ 0 ^ 1 ^ 5 ^ 4 ^ 7 ^ 6) = 0
Check Sum : (const5 + 3 + 7 + 5 + 0 + 1 + 5 + 4 + 7 + 6) and F = B
 

Example 2
0011 0111 0000 0000 0001 0101 0010 0111 0101 0011 
3 7 0 0 1 5 2 13 5 3 
Check Xor : (3 ^ 7 ^ 0 ^ 0 ^ 1 ^ 5 ^ 2 ^ 7 ^ 5) = 0
Check Sum : (const5 + 3 + 7 + 0 + 0 + 1 + 5 + 2 + 7 + 5) and F = 3
 

Example 3
0011 0111 0101 0010 0001 0000 0000 1000 1010 1001 
3 7 5 2 1 0 0 20 A 9 
Check Xor : (3 ^ 7 ^ 5 ^ 2 ^ 1 ^ 0 ^ 0 ^ 8 ^ A) = 0
Check Sum : (const5 + 3 + 7 + 5 + 2 + 1 + 0 + 0 + 8 + A) and F = 9
 

 Sensor type is 3
 Sensor Address 7
 Data values
 CheckXor
 Checksum

The first block is the LSB, so the values are repectively:

  1. [speed] 10.5 km/h - [direction] 145 deg ± 67.5 deg
  2. [speed] 10.0 km/h - [direction] 125 deg ± 67.5 deg
  3. [speed] 12.5 km/h - [direction] 200 deg ± 0.1 deg

Where is the hundred digit for speed ? I never got so much wind, so I could not isolate it.

I am interested by any comment or more information on the format of these frames. Contact: Jean-Paul ROUBELAT - F6FBB

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