diff --git a/README.md b/README.md index cb01414..a800845 100644 --- a/README.md +++ b/README.md @@ -2,20 +2,29 @@ ESP8266/ESP32 decrypts wireless MBus frames from a Multical21 water meter. Multical21 -A CC1101 868 MHz module is connected via SPI to the ESP8266/ESP32. + +### Hardware +The hardware you need: + + +The CC1101 868 MHz module is [connected](#d1-mini-connected-to-different-cc1101-modules) via SPI to the ESP8266/ESP32. + +### Software +The best approach to build this software is using PlatformIO. If you are not familiar with PlatformIO, [here](https://www.youtube.com/watch?v=JmvMvIphMnY) is a good place to start. + The Multical21 is transmitting encrypted MBus frames (Mode C1, frame type B) every 16 seconds. -The ESP8266/ESP32 does some validation (right serial number, crc checking) and then +The ESP8266/ESP32 does some validation (correct serial number, crc checking) and then decrypts them with AES-128-CTR. -The serial number (8 digits) is printed on the water meter (above the LCD). -Ask your water supplier for the decryption key (16 bytes). I got mine packed in a so called -KEM-file. To extract the key i used a python script [kem-decryptor.py](https://gist.github.com/mbursa/caa654a01b9e804ad44d1f00208a2490) - - +### Meter values The Multical21 provides the following meter values: