src/devices/efergy_optical.c

   1 /* Efergy IR is a devices that periodically reports current energy consumption
   2  * on frequency ~433.55 MHz. The data that is transmitted consists of 8
   3  * bytes:
   4  *
   5  * Byte 1-4: Start bits (0000), then static data (probably device id)
   6  * Byte 5-7: all zeros
   7  * Byte 8: Pulse Count
   8  * Byte 9: sample frequency (15 seconds)
   9  * Byte 10: seconds
  10  * Byte 11: bytes0-10 crc16 xmodem XOR with FF
  11  * Byte 12: ?crc16 xmodem
  12  * if pulse count <3 then energy =(( pulsecount/impulse-perkwh) * (3600/seconds))
  13  * else  energy= ((pulsecount/n_imp) * (3600/seconds))
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  */
  20
  21 #include "rtl_433.h"
  22 #include "util.h"
  23 #include "data.h"
  24
  25 static int efergy_optical_callback(bitbuffer_t *bitbuffer) {
  26         unsigned num_bits = bitbuffer->bits_per_row[0];
  27         uint8_t *bytes = bitbuffer->bb[0];
  28         double energy, n_imp;
  29         double pulsecount;
  30         double seconds;
  31         data_t *data;
  32         char time_str[LOCAL_TIME_BUFLEN];
  33         uint16_t crc;
  34         uint16_t csum1;
  35
  36         if (num_bits < 64 || num_bits > 100){
  37                 return 0;
  38                 }
  39
  40         // The bit buffer isn't always aligned to the transmitted data, so
  41         // search for data start and shift out the bits which aren't part
  42         // of the data. The data always starts with 0000 (or 1111 if
  43         // gaps/pulses are mixed up).
  44         while ((bytes[0] & 0xf0) != 0xf0 && (bytes[0] & 0xf0) != 0x00)
  45                 {
  46                 num_bits -= 1;
  47                 if (num_bits < 64)
  48                         {
  49                         return 0;
  50                         }
  51
  52                 for (unsigned i = 0; i < (num_bits + 7) / 8; ++i)
  53                         {
  54                         bytes[i] <<= 1;
  55                         bytes[i] |= (bytes[i + 1] & 0x80) >> 7;
  56                         }
  57                 }
  58
  59         // Sometimes pulses and gaps are mixed up. If this happens, invert
  60         // all bytes to get correct interpretation.
  61         if (bytes[0] & 0xf0){
  62                 for (unsigned i = 0; i < 12; ++i)
  63                         {
  64                         bytes[i] = ~bytes[i];
  65                         }
  66                 }
  67
  68          if (debug_output){
  69                 fprintf(stdout,"Possible Efergy Optical: ");
  70                 bitbuffer_print(bitbuffer);
  71                 }
  72
  73         // Calculate checksum for bytes[0..10]
  74         // crc16 xmodem with start value of 0x00 and polynomic of 0x1021 is same as CRC-CCITT (0x0000)
  75         // start of data, length of data=10, polynomic=0x1021, init=0x0000
  76
  77           csum1 = ((bytes[10]<<8)|(bytes[11]));
  78
  79           crc = crc16_ccitt(bytes, 10, 0x1021, 0x0);
  80
  81           if (crc == csum1)
  82                 {
  83                 if (debug_output) {
  84                 fprintf (stdout, "Checksum OK :) :)\n");
  85                 fprintf (stdout, "Calculated crc is 0x%02X\n", crc);
  86                 fprintf (stdout, "Received csum1 is 0x%02X\n", csum1);
  87                 }
  88                 // this setting depends on your electricity meter's optical output
  89                 n_imp = 3200;
  90
  91                 pulsecount =  bytes[8];
  92                 seconds = bytes[10];
  93
  94                 //some logic for low pulse count not sure how I reached this formula
  95                 if (pulsecount < 3)
  96                         {
  97                         energy = ((pulsecount/n_imp) * (3600/seconds));
  98                         }
  99                 else
 100                         {
 101                         energy = ((pulsecount/n_imp) * (3600/30));
 102                         }
 103                 //New code for calculating varous energy values for differing pulse-kwh values
 104                         const int imp_kwh[] = {3200, 2000, 1000, 500, 0};
 105                         for (unsigned i=0; imp_kwh[i] !=0; ++i) {
 106                                 if (pulsecount < 3)
 107                                         {
 108                                         energy = ((pulsecount/imp_kwh[i]) * (3600/seconds));
 109                                         }
 110                                 else
 111                                         {
 112                                         energy = ((pulsecount/imp_kwh[i]) * (3600/30));
 113                                         }
 114                                 local_time_str(0, time_str);
 115                                 data = data_make(
 116                                                 "time",          "Time",            DATA_STRING, time_str,
 117                                                 "model",         "Model",            DATA_STRING, "Efergy Optical",
 118                                                 "pulses",       "Pulse-rate",   DATA_FORMAT,"%i", DATA_INT, imp_kwh[i],
 119                                                 "energy",       "Energy",     DATA_FORMAT,"%.03f KWh", DATA_DOUBLE, energy,
 120                                                    NULL);
 121                                 data_acquired_handler(data);
 122                                 }
 123                                 return 0;
 124                 }
 125
 126                 else
 127                         {
 128                         if (debug_output)
 129                                 {
 130                                 fprintf (stdout, "Checksum not OK !!!\n");
 131                                 fprintf(stdout, "Calculated crc is 0x%02X\n", crc);
 132                                 fprintf(stdout, "Received csum1 is 0x%02X\n", csum1);
 133                                 }
 134                         }
 135                 return 0;
 136                 }
 137
 138 static char *output_fields[] = {
 139         "time",
 140         "model",
 141         "pulses",
 142         "energy",
 143         NULL
 144         };
 145
 146 r_device efergy_optical = {
 147         .name           = "Efergy Optical",
 148         .modulation     = FSK_PULSE_PWM_RAW,
 149         .short_limit    = 92,
 150         .long_limit     = 400,
 151         .reset_limit    = 400,
 152         .json_callback  = &efergy_optical_callback,
 153         .disabled       = 0,
 154         .demod_arg      = 0,
 155         .fields        = output_fields
 156 };