Note: if you find inaccuracies or have more info, please report using git Issues

Supported Efergy Energy Monitors
- Efergy E2 Classic (need exact model number?)
- Efergy Elite TPM (Reciever is RX-ELITE 3.0 (TPM-NA), sensor is ELITE-TPM-NA 1.0)
- Maybe others?

Instructions:
1) Get a working usb rtl-sdr device with the rtl_fm binary (probably from rtl-sdr library).

2) Check #defines in EfergyRPI_log.c to match your specific Efergy sensor/transmitter type

  In particular, check this one:
  #define VOLTAGE

  - With the default settings the program tries to decode up to 9 bytes of
    message data and checks for both 1 byte checksum and the 2 byte CRC.

3) Compile using: gcc -O3 -o EfergyRPI_log EfergyRPI_log.c  -lm 

4) Run program and review program help

  ./EfergyRPI_log -help

5) Find optimal frequency and gain values by analyzing rtl_fm output in debug mode

  rtl_fm -f 433.55e6 -s 200000 -r 96000 -A fast | ./EfergyRPI_log -d
  
   - Adjust frequency (-f) by .1 plus or minus until debug output
     shows wave center close to 0 and solid decode.
   - Gain (-g) may or may not be needed.  Some folks had best results
     by adding -g 19.7 to rtl_fm
 
6) Run in normal mode to output parsed energy usage info

   rtl_fm -f 433.55e6 -s 200000 -r 96000 -A fast 2>/dev/null | ./EfergyRPI_log

7) Run in log mode to send parsed energy usage info to log file

   rtl_fm -f 433.55e6 -s 200000 -r 96000 -A fast 2>/dev/null | ./EfergyRPI_log logfile