void serialEvent() {
  //bool doEval = false;
  while (Serial.available()) {
    char ch = Serial.read();
    cmdBuffer[cmdBufferCount] = ch;

    if ((ch == 13 || ch == 10)) { // ASCII code 13 = "CR", 10 = "LF"
      cmdBuffer[cmdBufferCount] = 0; // nullterminator
      //Serial.print("CR_  ");
      //Serial.print(cmdBuffer);
      //evalCmd();
      if (cmdBufferCount >= 1) evalCmd();
      else {
        cmdBufferCount = 0;
        for ( int i = 0; i < sizeof(cmdBuffer);  ++i ) cmdBuffer[i] = (char)0;
      }
    }
    //    else if (ch == 10 && cmdBufferCount > 1) { // ASCII code 10 = "LF"
    //      cmdBuffer[cmdBufferCount] = 0; // nullterminator
    //      //Serial.print("LF__  ");
    //      //Serial.print(cmdBuffer);
    //      //evalCmd();
    //      doEval = true;
    //    }
    else {
      cmdBufferCount++;
    }
  }
}



void evalCmd() {
  if (debug) {
    Serial.print("cmd: '");
    Serial.print(cmdBuffer);
    Serial.println("'");
    //Serial.println(strlen(cmdBuffer));
  }

  // begin commands
  if (strncmp(cmdBuffer, "ID", 2) == 0 && strlen(cmdBuffer) == 2) {
    Serial.print(PROJECT_NAME);
    Serial.print(" v");
    Serial.print(PROJECT_VERSION);
    Serial.println();
  }

  else if (strncmp(cmdBuffer, "get eeprom", 10) == 0 && strlen(cmdBuffer) == 10) {
    getEEPROMContent();
  }

  else if (strncmp(cmdBuffer, "save data", 9) == 0 && strlen(cmdBuffer) == 9) {
    saveAllCurrentData(false);
  }

  else if (strncmp(cmdBuffer, "debug 1", 7) == 0 && strlen(cmdBuffer) == 7) {
    debug = true;
    debuglevel = 1;
    byte tmpval = 1;
    Serial.println(F("DEBUG ENABLED"));
    EEPROM.put(eeprom_addr_debug, tmpval);
  }
  else if (strncmp(cmdBuffer, "debug 0", 7) == 0 && strlen(cmdBuffer) == 7) {
    debug = false;
    debuglevel = 0;
    byte tmpval = 0;
    Serial.println(F("DEBUG DISABLED"));
    EEPROM.put(eeprom_addr_debug, tmpval);
  }

  else if (strncmp(cmdBuffer, "format all", 10) == 0 && strlen(cmdBuffer) == 10) {
    formatEEPROM_AllData();
  }

  else if (strncmp(cmdBuffer, "format c", 8) == 0 && strlen(cmdBuffer) >= 8) {
    if (strlen(cmdBuffer) == 8) {
      Serial.println(F("missing counter number"));
    }
    else if (strlen(cmdBuffer) == 9) {
      char _tmpcNum[2];
      _tmpcNum[0] = cmdBuffer[8];
      _tmpcNum[1] = '\0';
      byte _cNum = atoi(_tmpcNum);
      //Serial.println(_cNum);
      if (_cNum > 0 && _cNum <= COUNTERS_COUNT) {
        formatEEPROMAreaOfCounter(_cNum - 1);
      }
      else {
        Serial.println(F("invalid counter number"));
      }
    }
  }

  else if (strncmp(cmdBuffer, "get readings", 12) == 0 && strlen(cmdBuffer) == 12) {
    printCurrentReadings();
  }

  else if (strncmp(cmdBuffer, "get imp c", 9) == 0 && strlen(cmdBuffer) >= 9) {
    if (strlen(cmdBuffer) == 9) {
      Serial.println(F("missing counter number"));
    }
    else if (strlen(cmdBuffer) == 10) {
      char _tmpcNum[2];
      _tmpcNum[0] = cmdBuffer[9];
      _tmpcNum[1] = '\0';
      byte _cNum = atoi(_tmpcNum);
      //Serial.println(_cNum);
      if (_cNum > 0 && _cNum <= COUNTERS_COUNT) {
        restoreLastSavedImpulseCount(_cNum - 1, true);
      }
      else {
        Serial.println(F("invalid counter number"));
      }
    }
  }

  else if (strncmp(cmdBuffer, "get pwrgood", 11) == 0 && strlen(cmdBuffer) == 11) {
    printPowerValue();
  }

  else if (strncmp(cmdBuffer, "set pwrgood", 11) == 0 && strlen(cmdBuffer) >= 13) {
    uint16_t tmpvalue = 0;
    char offset = 13;
    char len = strlen(cmdBuffer) - offset;
    if (strlen(cmdBuffer) >= offset) {
      for (char i = 0; i < len; i++) {
        if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
      }
      cmdDataBuffer[len] = '\0';
      //Serial.println();
      //Serial.print("'");
      //Serial.print(cmdDataBuffer);
      //Serial.println("'");

      char _value1[6];
      uint8_t _ivalue1;
      byte _i2 = 0;
      for (byte i = offset; i < strlen(cmdBuffer); i++) {
        _value1[_i2] = cmdBuffer[i];
        _i2++;
      }
      _value1[_i2] = '\0';
      _ivalue1 = atoi(_value1);

      if (_ivalue1 >= 0 && _ivalue1 <= 1023) {
        Serial.print(F("RES: set pwrGood="));
        Serial.print(_ivalue1);
        Serial.println();
        powerGoodMinValue = _ivalue1;
      }

      saveGlobalConfig();

    }
  }

  else if (strncmp(cmdBuffer, "set json 0", 10) == 0 && strlen(cmdBuffer) == 10) {
    output_json = false;
    byte tmpval = 0;
    EEPROM.put(eeprom_addr_output_json, tmpval);
  }

  else if (strncmp(cmdBuffer, "set json 1", 10) == 0 && strlen(cmdBuffer) == 10) {
    output_json = true;
    byte tmpval = 1;
    EEPROM.put(eeprom_addr_output_json, tmpval);
  }

  else if (strncmp(cmdBuffer, "get conf", 8) == 0 && strlen(cmdBuffer) >= 8) {
    //    if (strlen(cmdBuffer) > 8 && cmdBuffer[8] == ' ' && cmdBuffer[9] == 'c') {
    //      // is "get conf c#"
    //      if (strlen(cmdBuffer) == 10) {
    //        Serial.println(F("missing counter number"));
    //      }
    //      else {
    //        uint16_t tmpvalue = 0;
    //        char offset = 10;
    //        char len = strlen(cmdBuffer) - offset;
    //        if (strlen(cmdBuffer) >= offset) {
    //          for (char i = 0; i < len; i++) {
    //            if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
    //          }
    //          cmdDataBuffer[len] = '\0';
    //          //Serial.println(cmdDataBuffer);
    //          tmpvalue = atoi(cmdDataBuffer);
    //          if (tmpvalue > 0 && tmpvalue <= COUNTERS_COUNT) {
    //            //Serial.print("conf counter ");
    //            //Serial.println(tmpvalue);
    //            printCounterConf(tmpvalue - 1);
    //          }
    //          else {
    //            Serial.println(F("counter number invalid"));
    //          }
    //
    //        }
    //      }
    //    }
    //    else {
    // // is "get conf" - so show all
    printGlobalConf();
    for (byte i = 0; i < COUNTERS_COUNT; i++) {
      printCounterConf(i);
    }
    //    }
  }

  else if (strncmp(cmdBuffer, "set debounce", 12) == 0 && strlen(cmdBuffer) >= 14) {
    uint16_t tmpvalue = 0;
    char offset = 13;
    char len = strlen(cmdBuffer) - offset;
    if (strlen(cmdBuffer) >= offset) {
      for (char i = 0; i < len; i++) {
        if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
      }
      cmdDataBuffer[len] = '\0';
      //Serial.println();
      //Serial.print("'");
      //Serial.print(cmdDataBuffer);
      //Serial.println("'");

      char _value1[6];
      char _value2[6];
      uint8_t _ivalue1, _ivalue2;
      bool _withValue2;
      byte _sepOffset = 0;
      byte _i2 = 0;
      for (byte i = offset; i < strlen(cmdBuffer); i++) {
        if (cmdBuffer[i] == ',') {
          //Serial.print("found , at offset ");
          //Serial.println(i);
          _sepOffset = i;
        }
        else if (_sepOffset == 0) {
          _value1[_i2] = cmdBuffer[i];
          _i2++;
        }
      }
      _value1[_i2] = '\0';

      if (_sepOffset > 0) {
        _i2 = 0;
        for (byte i = _sepOffset + 1; i < strlen(cmdBuffer); i++) {
          _value2[_i2] = cmdBuffer[i];
          _i2++;
        }
        _value2[_i2] = '\0';
        _withValue2 = true;
      }
      else {
        _value2[0] = '\0'; // no _value2 was given
        _withValue2 = false;
      }

      _ivalue1 = atoi(_value1);
      _ivalue2 = atoi(_value2);

      if (_ivalue1 >= 0 && _ivalue1 <= 200) {
        Serial.print(F("RES: set debounce="));
        Serial.print(_ivalue1);
        debounceDelay = _ivalue1;
      }

      if (_withValue2 && _ivalue2 >= 0 && _ivalue2 <= 500) {
        Serial.print(F(", debounceRecov="));
        Serial.print(_ivalue2);
        debounceRecoveryDelay = _ivalue2;
      }
      Serial.println();

      saveGlobalConfig();

    }
  }

  else if (strncmp(cmdBuffer, "get debounce", 12) == 0 && strlen(cmdBuffer) == 12) {
    Serial.print(F("debounce: "));
    Serial.print(debounceDelay);
    Serial.print(", ");
    Serial.println(debounceRecoveryDelay);
  }

  else if (strncmp(cmdBuffer, "set conf c", 10) == 0 && strlen(cmdBuffer) >= 10) {
    if (strlen(cmdBuffer) == 10) {
      Serial.println(F("missing counter number"));
    }
    else if (strlen(cmdBuffer) >= 15) {
      uint16_t tmpvalue = 0;
      char offset = 10;
      char len = strlen(cmdBuffer) - offset;
      if (strlen(cmdBuffer) >= offset) {
        char _cNumBuf[2];
        char _commandBuffer[11];
        char _valueBuffer[11];
        //byte _delimitersFound = 0;
        byte _cNum;
        boolean _cNumOK = false;
        //
        for (byte i = 0; i < len; i++) {
          if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
        }
        cmdDataBuffer[len] = '\0';
        Serial.print("cmdDataBuffer: '");
        Serial.print(cmdDataBuffer);
        Serial.println("'");

        // get counter number, expect it on 1st place and 1 char long
        _cNumBuf[0] = cmdDataBuffer[0];
        _cNumBuf[1] = '\0';
        _cNum = atoi(_cNumBuf);

        if (_cNum > 0 && _cNum <= COUNTERS_COUNT) {
          Serial.print("_cNum=");
          Serial.println(_cNum);
          _cNumOK = true;
        }
        else if (cmdDataBuffer[1] != ' ') {
          Serial.println(F("ERROR - invalid syntax"));
        }
        else {
          Serial.print("_cNum invalid: ");
          Serial.println(_cNum);
        }

        //        Serial.println();
        //        Serial.print("cmdDataBuffer[1]='");
        //        Serial.print(cmdDataBuffer[1]);
        //        Serial.println("'");


        if (_cNumOK && strlen(cmdDataBuffer) > 4) {
          // https://arduino.stackexchange.com/questions/1013/how-do-i-split-an-incoming-string
          // Read each command pair
          char* _param = strtok(cmdDataBuffer, " ");
          while (_param != 0)
          {
            // Split the command in two values
            char* _value = strchr(_param, '=');
            if (_value != 0)
            {
              // Actually split the string in 2: replace ':' with 0
              *_value = 0;
              strlwr(_param);

              //              Serial.print("_param='");
              //              Serial.print(_param);

              ++_value;

              //              Serial.print("'   ");
              //              Serial.print("_value='");
              //              Serial.print(_value);
              //              Serial.println("'");

              if (strcmp(_param, "impperunit") == 0) {
                Serial.print("impPerUnit=");
                Serial.println(atoi(_value));
                meter_impPerUnit[_cNum - 1] = atoi(_value);
              }
              else if (strcmp(_param, "noimptout") == 0) {
                Serial.print("noImpTout=");
                Serial.println(atoi(_value));
                meter_noImpulseTimeout_seconds[_cNum - 1] = atoi(_value);
              }
              else if (strcmp(_param, "saveint") == 0) {
                Serial.print("saveInt=");
                Serial.println(atoi(_value));
                meter_savePulsesOnInterval_mins[_cNum - 1] = atoi(_value);
              }
              else {
                Serial.print(F("unknown parameter '"));
                Serial.print(_param);
                Serial.println("'");
              }

              printCounterConf(_cNum - 1);

            }
            // Find the next command in input string
            _param = strtok(0, ";");
          }
        }
        else {
          Serial.println(F("invalid command"));
        }
      }
    }
  }

  else if (strncmp(cmdBuffer, "save conf", 9) == 0 && strlen(cmdBuffer) == 9) {
    Serial.println(F("SAVING CONFIG"));
    saveCountersConfig();
    saveGlobalConfig();
  }

#ifdef INCLUDE_TESTFUNCTIONS
  else if (strncmp(cmdBuffer, "test init c2", 12) == 0 && strlen(cmdBuffer) == 12) {
    Serial.println("test init c2");
    
    formatEEPROMAreaOfCounter(1);
    
    eeprom_writecounter_currentReadingImpulses[1] = 65530;
    eeprom_nextoffset_currentReadingImpulses[1] = 0;
  }
  
  else if (strncmp(cmdBuffer, "test c2", 7) == 0 && strlen(cmdBuffer) == 7) {
    increaseCounter(1);
    storeCurrentImpulses(1, false);
  }
#endif

  else if (strncmp(cmdBuffer, "set reading", 11) == 0 && strlen(cmdBuffer) >= 11) {
    uint16_t tmpvalue = 0;
    char tmpdata_1[10];
    char tmpdata_2[10];
    unsigned long newReading;
    uint16_t newImpulses;

    if (strlen(cmdBuffer) <= 13) {
      Serial.println(F("ERROR: missing valid counter number"));
    }
    else if ( strlen(cmdBuffer) > 13 && cmdBuffer[11] == ' ' && cmdBuffer[12] == 'c') {
      byte _cNum;

      char tmp_cNum[2];
      tmp_cNum[0] = cmdBuffer[13];  // atoi needs char array to work...
      tmp_cNum[1] = 0;
      _cNum = atoi(tmp_cNum);

      if (_cNum < 1 || _cNum > COUNTERS_COUNT) {
        Serial.println(F("ERROR: invalid counter number"));
      }
      else if (_cNum > 0 && _cNum <= COUNTERS_COUNT) {
        Serial.print(F("got valid counter number: "));
        Serial.println(_cNum);

        _cNum = _cNum - 1; // we actually need the array index, not the pretty number...

        //char offset = 12;
        byte offset = 15;
        byte len = strlen(cmdBuffer) - offset;
        Serial.println("SET READING");

        if (strlen(cmdBuffer) > offset) {
          //for (char i = 0; i < len; i++) {
          //  if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
          //}
          bool value_1_finished = false;
          bool value_2_finished = false;
          bool commaGiven = false;
          bool impulsesGiven = false;
          uint8_t i1 = 0;
          uint8_t i2 = 0;
          //Serial.println("vor val1");
          while (!value_1_finished) {
            if (isdigit(cmdBuffer[i1 + offset])) {
              if (i1 < (sizeof(tmpdata_1) - 1)) tmpdata_1[i1] = cmdBuffer[i1 + offset];
              //Serial.print("  ");
              //Serial.print(i1);
              i1++;
              i2++;
            }
            else if (cmdBuffer[i1 + offset] == '.' || cmdBuffer[i1 + offset] == ',' || cmdBuffer[i1 + offset] == ' ') {
              value_1_finished = true;
              if (cmdBuffer[i1 + offset] == '.' || cmdBuffer[i1 + offset] == ',') commaGiven = true;
              //Serial.println("value_1_finished=true");
              i1++;
            }
            else if (cmdBuffer[i1 + offset] == '\0') {
              //Serial.println("value_[1|2]_finished=true");
              value_1_finished = true;
              value_2_finished = true; // end of string reached - no value 2 was given
            }
          }
          tmpdata_1[i2] = '\0';
          newReading = atol(tmpdata_1);
          //Serial.print(F("value 1: "));
          //Serial.println(tmpdata_1);


          if (!value_2_finished) {
            impulsesGiven = true;
            i2 = 0;
            while (!value_2_finished) {
              if (isdigit(cmdBuffer[i1 + offset])) {
                if (i2 < (sizeof(tmpdata_2) - 1)) tmpdata_2[i2] = cmdBuffer[i1 + offset];
                i1++;
                i2++;
              }
              else if (cmdBuffer[i1 + offset] == ' ' || cmdBuffer[i1 + offset] == '\0') {
                value_2_finished = true; // end of string reached
              }
            }
            tmpdata_2[i2] = '\0';
            newImpulses = atoi(tmpdata_2);
            //Serial.print(F("value 2: "));
            //Serial.println(tmpdata_2);
          }

          if (commaGiven && impulsesGiven && tmpdata_2 >= 0) {
            if ((meter_impPerUnit[_cNum] == 10 && newImpulses < 10) || (meter_impPerUnit[_cNum] == 100 && newImpulses < 100) || (meter_impPerUnit[_cNum] == 1000 && newImpulses < 1000) || (meter_impPerUnit[_cNum] == 10000 && newImpulses < 10000)) {
              Serial.print(F("INFO: set new reading: "));
              Serial.print(newReading);
              Serial.print(".");

              if (meter_impPerUnit[_cNum] == 100 && newImpulses < 10) Serial.print("0");
              else if (meter_impPerUnit[_cNum] == 1000 && newImpulses < 10) Serial.print("00");
              else if (meter_impPerUnit[_cNum] == 1000 && newImpulses < 100) Serial.print("0");
              Serial.println(newImpulses);

              currentReading[_cNum] = newReading;
              currentReadingImpulses[_cNum] = newImpulses;
              formatEEPROMAreaOfCounter(_cNum);
              storeCurrentReading(_cNum, true);
              storeCurrentImpulses(_cNum, true);
            }
            else {
              Serial.print(F("ERROR: invalid decimals for set impPerUnit="));
              Serial.print(meter_impPerUnit[_cNum]);
              Serial.println(" !!!");
            }
          }
          else if (!commaGiven && impulsesGiven) {
            Serial.print(F("INFO: set new reading: "));
            Serial.println(newReading);
            Serial.print(F("INFO: set new impulses: "));
            Serial.println(newImpulses);
            currentReading[_cNum] = newReading;
            currentReadingImpulses[_cNum] = newImpulses;
            formatEEPROMAreaOfCounter(_cNum);
            storeCurrentReading(_cNum, true);
            storeCurrentImpulses(_cNum, true);
          }
          else if (!commaGiven && !impulsesGiven) {
            Serial.print(F("INFO: set new reading: "));
            Serial.println(newReading);
            currentReading[_cNum] = newReading;
            currentReadingImpulses[_cNum] = 0;
            formatEEPROMAreaOfCounter(_cNum);
            storeCurrentReading(_cNum, true);
            storeCurrentImpulses(_cNum, true);
          }
        }
      }
    }
  }

  else if (strncmp(cmdBuffer, "get wcount", 10) == 0 && strlen(cmdBuffer) == 10) {
    for (int i = 0; i < COUNTERS_COUNT; i++) {
      Serial.print(F("wCount C"));
      Serial.print(i + 1);
      Serial.print("=");
      Serial.println(eeprom_writecounter_currentReadingImpulses[i]);
    }
  }

  else if (strncmp(cmdBuffer, "reset", 5) == 0 && strlen(cmdBuffer) >= 5) {
    if (strlen(cmdBuffer) == 5) {
      resetForFlashing(0);
    }
    else {
      uint16_t tmpvalue = 0;
      char offset = 6;
      char len = strlen(cmdBuffer) - offset;
      if (strlen(cmdBuffer) >= offset) {
        for (char i = 0; i < len; i++) {
          if (i < (sizeof(cmdDataBuffer) - 1)) cmdDataBuffer[i] = cmdBuffer[i + offset];
        }
        cmdDataBuffer[len] = '\0';
        Serial.println(cmdDataBuffer);
        tmpvalue = atoi(cmdDataBuffer);
        if (tmpvalue >= 0 && tmpvalue <= 15000) {
          resetForFlashing(tmpvalue);
        }
        else Serial.println(F("out of range 0-15000"));
      }
    }
  }

  else {
    Serial.print(F("UNKNOWN COMMAND: '"));
    Serial.print(cmdBuffer);
    Serial.println("'");
  }



  cmdBufferCount = 0;
  for ( int i = 0; i < sizeof(cmdBuffer);  ++i ) cmdBuffer[i] = (char)0;
}