Protocol of the Lacrosse WS7000-22/25 meteo sensor

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

10bits of 0 (start sequence) [blue]
10 blocks of four bits separated by a bit 1 [red] to be checked and skipped

Example 1

Example 2

Example 3

When extracting data from the examples, we get:
Example 1
1 0 0 0 0 1 1 0 1 1 1 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 1 1 1 1 0 1 0 1 1 1 1 0 0

Example 2
1 0 0 0 0 1 1 0 0 1 0 0 1 1 1 0 1 1 0 0 0 0 0 0 1 0 0 0 1 0 1 0 1 0 1 0 1 1 0 0

Example 3
1 0 0 0 0 1 1 1 1 1 1 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 1 1 0 0 0 1 1 1 0 0 0

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
0 0 0 1 0 1 1 0 0 1 1 1 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 1 0 1 1 1 1 1 0 1 0 0 1 1
1 + 6 7 2 1 0 9 7 D 3
Check Xor : (1 ^ 6 ^ 7 ^ 2 ^ 1 ^ 0 ^ 9 ^ 7 ^ D) = 0
Check Sum : (const5 + 1 + 6 + 7 + 2 + 1 + 0 + 9 + 7 + D) and F = 3

Example 2
0 0 0 1 0 1 1 0 0 0 1 0 0 1 1 1 0 0 1 1 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 1 0 0 1 1
1 + 6 2 7 3 0 1 5 5 3
Check Xor : (1 ^ 6 ^ 2 ^ 7 ^ 3 ^ 0 ^ 1 ^ 5 ^ 5) = 0
Check Sum : (const5 + 1 + 6 + 2 + 7 + 3 + 0 + 1 + 5 + 5) and F = 3

Example 3
0 0 0 1 1 1 1 0 0 1 1 1 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 1 0 1 1 0 1 1 0 0 0 0 0 1
1 - 6 7 2 1 0 1 6 C 1
Check Xor : (1 ^ E ^ 7 ^ 2 ^ 1 ^ 0 ^ 1 ^ 6 ^ C) = 0
Check Sum : (const5 + 1 + E + 7 + 2 + 1 + 0 + 1 + 6 + C) and F = 1

Sensor type is 1

Temperature is positive

Sensor Address

Data values

CheckXor

Checksum

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

[temp] 12.7 deg - [hygro] 79.0 %
[temp] 37.2 deg - [hygro] 51.0 %
[temp] -12.7 deg - [hygro] 61.0 %

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

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0	0	0	1	0	1	1	0	0	1	1	1	0	0	1	0	0	0	0	1	0	0	0	0	1	0	0	1	0	1	1	1	1	1	0	1	0	0	1	1
1				+	6			7				2				1				0				9				7				D				3
Check Xor : (1 ^ 6 ^ 7 ^ 2 ^ 1 ^ 0 ^ 9 ^ 7 ^ D) = 0 Check Sum : (const5 + 1 + 6 + 7 + 2 + 1 + 0 + 9 + 7 + D) and F = 3

0	0	0	1	0	1	1	0	0	0	1	0	0	1	1	1	0	0	1	1	0	0	0	0	0	0	0	1	0	1	0	1	0	1	0	1	0	0	1	1
1				+	6			2				7				3				0				1				5				5				3
Check Xor : (1 ^ 6 ^ 2 ^ 7 ^ 3 ^ 0 ^ 1 ^ 5 ^ 5) = 0 Check Sum : (const5 + 1 + 6 + 2 + 7 + 3 + 0 + 1 + 5 + 5) and F = 3

0	0	0	1	1	1	1	0	0	1	1	1	0	0	1	0	0	0	0	1	0	0	0	0	0	0	0	1	0	1	1	0	1	1	0	0	0	0	0	1
1				-	6			7				2				1				0				1				6				C				1
Check Xor : (1 ^ E ^ 7 ^ 2 ^ 1 ^ 0 ^ 1 ^ 6 ^ C) = 0 Check Sum : (const5 + 1 + E + 7 + 2 + 1 + 0 + 1 + 6 + C) and F = 1

	Sensor type is 1
	Temperature is positive
	Sensor Address
	Data values
	CheckXor
	Checksum