uh50reader.h

//-------------------------------------------------------------------------------------
// ESPHome Landis+Gyr Ultraheat UH50 (T550) Heat Meter custom sensor
// Copyright 2020 Pär Svanström
// 
// History
//  0.1.0 2021-02-03:   Initial release
//
// MIT License
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), 
// to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, 
// and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 
// IN THE SOFTWARE.
//-------------------------------------------------------------------------------------

#include "esphome.h"

#define BUF_SIZE 2500
#define WAIT_TIME 1

byte data_cmd[] = { 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  '/',  '#' , '!', 0x0D, 0x0A
};

// Landis & Gyr EN 61107 mode B protocol
// http://manuals.lian98.biz/doc.en/html/u_iec62056_struct.htm
// https://www.ungelesen.net/protagWork/media/downloads/solar-steuerung/iec62056-21%7Bed1.0%7Den_.pdf
// http://tunn.us/arduino/landisgyr.php
// https://www.elvaco.se/Image/GetDocument/en/286/cmi4110-users-manual-english.pdf
// https://github.com/lvzon/dsmr-p1-parser/blob/master/doc/IEC-62056-21-notes.md
// http://womp3-14.vijfwal.nl/p2013c.html

class UH50Reader : public Component, public UARTDevice, public CustomAPIDevice {
  const char* DELIMITERS = "(*";
  UARTDevice uart_out;
  unsigned long timeLastRun;
  char buffer[BUF_SIZE];

  public:
    Sensor *cumulativeActiveImport = new Sensor();
    Sensor *cumulativeVolume = new Sensor();
    Sensor *currentPower = new Sensor();
    Sensor *flowRate = new Sensor();
    Sensor *temperatureFlow = new Sensor();
    Sensor *temperatureReturn = new Sensor();
    Sensor *temperatureDiff = new Sensor();

    UH50Reader(UARTComponent *uart_in, UARTComponent *uart_out) : UARTDevice(uart_in), uart_out(uart_out) { }

    void setup() override {
      sendDataCmd();
      timeLastRun = millis() - (WAIT_TIME - 1) * 60000;

      //register the service which Home Assistant can call to read the meter
      register_service(&UH50Reader::read_meter, "start_read_meter");
    }

    void loop() override {
      if (millis() - timeLastRun > WAIT_TIME * 60000) {
        sendDataCmd();
        readTelegram();
        timeLastRun = millis();
      }
    }

    void read_meter() {
        sendDataCmd();
        readTelegram();
    }

  private:

    void publishSensors(OBISData *od, int count) {

      for (int i=0; i < count; i++) {
	if (!strcmp(od[i].obis_code, "6.8"))
          cumulativeActiveImport->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.26"))
          cumulativeVolume->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.4"))
          currentPower->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.27"))
          flowRate->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.29"))
          temperatureFlow->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.28"))
          temperatureReturn->publish_state(atof(od[i].value));
	else if (!strcmp(od[i].obis_code, "6.30"))
          temperatureDiff->publish_state(atof(od[i].value));
      }
    }

    void sendDataCmd() {
      for (int i = 0; i < sizeof(data_cmd); i++) {
        uart_out.write(data_cmd[i]);
      }
      ESP_LOGI("cmd", "data cmd sent");
    }

    void readTelegram() {
      OBISData obisdata[MAX_OBIS_CODES];
      
      bool publish=false;
      // fast forward until we find the STX byte (start-of-text)
      byte b = 0x00;
      while (available() && b != 0x02) {
        b = read();
      }

      while (int len = available()) {
        ESP_LOGD("readTelegram", "Got %d bytes available to read", len);
        if (!read_array((uint8_t *) buffer, len))
               ESP_LOGW("readTelegram", "read_array() returned false, meter reading may be incomplete");
        ESP_LOGD("readTelegram", "Read %s", buffer);

	int count;
	parse_obis(buffer, obisdata, &count);
	print_parsed_data(obisdata, count);
        publishSensors(obisdata, count);

        // clean buffer
        memset(buffer, 0, BUF_SIZE - 1);

      }
    }
};