Arduino library to receive and decode data of wireless weather sensors manufactured by ELV, like the S 300, ASH 2200, and KS 300. The communication protocol is also compatible to self-made sensors based on the TempHygroTX868 arduino library.
The software uses the ELV RX868 868.35 MHz receiver module to receive the data of the sensors, decodes it and prints it in human readable or LogView format compatible to the USB-WDE1.
As a bonus, the decoder runs on the Raspberry Pi as well. See sub-directory raspi-wiringPi.
- RX868 receiver
- Arduino Uno, Nano, Pro Mini etc.
Arduino RX868
D3 ___________ DATA
GND __________ GND
5V/3V3 _______ +UB (The receiver works with 3.3V and 5V)
|_ EN
- Install this library:
- Download WeatherRX868.zip from releases page
- Or clone this git repo into the libraries folder of your Arduino Installation
- Follow the steps described at Installing Additional Arduino Libraries
- Connect RX868 receiver to Arduino
- Open the sketch from File - Examples - WeatherRX868
- Upload the sketch to the Arduino
- View output on the serial console at 57600 bps
Source: dc3yc
- On-off keying with constant length of pulses of 1220.7µs
- One pulse codes a logical 0 or 1
- Logical 0: 854.5µs on and 366.2µs off
- Logical 1: 366.2µs on and 854.5µs off
- Data is grouped into nibbles of 4 bit with LSB first. Each nibble is terminated with 1.
| Data | Meaning |
|---|---|
| 0000000 | synchronisation (up to 10 bits) |
| 1 | start bit |
| 10001 | sensor type: 1 |
| AAA | address (0..7) |
| S1 | sign of temperature, S==0 => positive |
| TTTT1 | temperature digit with weight 0.1 |
| TTTT1 | temperature digit with weight 1 |
| TTTT1 | temperature digit with weight 10 |
| HHHH1 | humidity digit with weight 0.1 |
| HHHH1 | humidity digit with weight 1 |
| HHHH1 | humidity digit with weight 10 |
| QQQQ1 | check: XOR of data from sensor type to check - must be 0 |
| SSSS1 | sum of data from sensor type to check + 5 AND 0xF |
0000000110001011010001100001010010110110011101011110110001
Thermo/Hygro Sensor (type 1), address 6, temperature 20.8 °C, rel. humidity 59.6 %
| Data | Meaning |
|---|---|
| 0000000 | synchronisation (up to 10 bits) |
| 1 | start bit |
| 11101 | sensor type: 7 |
| 1R0 | rain detector R==1 => it is raining |
| S1 | sign of temperature, S==0 => positive |
| TTTT1 | temperature digit with weight 0.1 |
| TTTT1 | temperature digit with weight 1 |
| TTTT1 | temperature digit with weight 10 |
| HHHH1 | humidity digit with weight 1 |
| HHHH1 | humidity digit with weight 10 |
| WWWW1 | wind speed digit with weight 0.1 |
| WWWW1 | wind speed digit with weight 1 |
| WWWW1 | wind speed digit with weight 10 |
| CCCC1 | amount of rainfall bit 0..4 |
| CCCC1 | amount of rainfall bit 5..8 |
| CCCC1 | amount of rainfall bit 9..12 |
| XXXX1 | ? |
| QQQQ1 | check: XOR of data from sensor type to check - must be 0 |
| SSSS1 | sum of data from sensor type to check + 5 AND 0xF |
11101100011110100011100010001101101000010000100001101111110100001101111000110111
Kombi Sensor (type 7), temperature 18.7 °C, rel. humidity 68 %, wind speed 0.0 km/h, rainfall 125
The sample sketch WeatherRX868 contains two different functions to send the decoded date to the serial port. You may use the one that fits your needs or code another one.
printDecoderOutput: Prints data in human readable format that should be self-explaining.
handleLogViewOutput: Prints data in LogView format that is compatible to the USB-WDE1. The data is printed line by line, each line contains one field per sensor value, the fields are separated by semicolon ;
| Data field | Meaning |
|---|---|
| $1; | start of record |
| 1; | state (always 1) |
| ; | timeStamp (always empty) |
| dd.d; | temperature sensor address 0 |
| dd.d; | temperature sensor address 1 |
| dd.d; | temperature sensor address 2 |
| dd.d; | temperature sensor address 3 |
| dd.d; | temperature sensor address 4 |
| dd.d; | temperature sensor address 5 |
| dd.d; | temperature sensor address 6 |
| dd.d; | temperature sensor address 7 |
| dd.d; | humidity sensor address 0 |
| dd.d; | humidity sensor address 1 |
| dd.d; | humidity sensor address 2 |
| dd.d; | humidity sensor address 3 |
| dd.d; | humidity sensor address 4 |
| dd.d; | humidity sensor address 5 |
| dd.d; | humidity sensor address 6 |
| dd.d; | humidity sensor address 7 |
| dd.d; | temperature Kombisensor |
| dd.d; | humidity Kombisensor |
| dd.d; | wind speed |
| ddd; | amount of rainfall |
| d; | rain detector |
| 0\r\n | end of record |
$1;1;;27.7;24.7;;;21.2;;25.4;;0.0;43.9;;;64.9;;54.9;;30.0;33.0;0.0;42;0;0
Copyright 2015, 2020 Martin Kompf
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.