RCS RS485 thermostat

[dbemowsk]

@pjr OK, that helps me understand your code better. I am assuming that the "onModbusProcessed" method is to process incoming messages sent by the modbus network and sending them to Domoticz, correct? Processing incoming messages from the RS485 network is where some of my problems are in my setup. I will try tonight to make some code changes to see if I can get it working. My main problem was my cooling set point was not updating in Domoticz correctly. The Heat set point and temp seemed to work. I'll post my findings.

[pjr]

@dbemowsk said:

@pjr OK, that helps me understand your code better. I am assuming that the "onModbusProcessed" method is to process incoming messages sent by the modbus network and sending them to Domoticz, correct?

Thats correct. There I handle the result of a modbus query.
I'm not handling decimals since the heat pump controller supports only full numbers..

[dbemowsk]

So last night I figured out my issue with why my code was not updating the set point cool value. Turns out it was the way I was parsing the string passed from the RS485 side to it's key/value pairs. The string that it was working on was this:

A=0 O=01 T=73.4 SPH=72.1 SPC=70.0\r

The code I had was only taking the key/value pairs up to the last one because I had it keying off of the space character. Since there was no trailing space in the string, the last pair got skipped which was the cooling set point.

I will post some updated code once I get a little more done.

[dbemowsk]

OK, so I had this project on hold for a while and am getting back to it. My issue now is that for some reason I am not receiving messages from Domoticz for this node. If I send a temp set point or status from the RS485 side, it updates in Domoticz, but if I try to change a set point or status in Domoticz, the MySensors node doesn't receive it. The code is a bit messy right now, but it should work with what I have. If someone could look it over and advise, that would be a big help. The sketch is a MySensors 1.5.4 sketch.

 /*
  RCS Thermostat for MySensors

  Arduino RCS RS485 thermostat control

  July 7,2016

  This is a gateway bridge to allow an RCS serial thermostat to be accessible to a MySensors
  gateway.  The thermostat being used to test this is an RCS TR40 RS485 thermostat.  The published
  protocol for RCS thermostats can be found at the following address;
  http://www.rcstechnology.com/oldsite/docs/thermostats/serial/SERIAL%20PROTOCOL%20REV%204.3%20%20150-00225-43.pdf
  
  This sketch features the following:

  Add features here
 */

// Import needed libraries
#include <SPI.h>
#include <MySensor.h>  
#include <SoftwareSerial.h>

#define SKETCH_NAME "RCS TR40 Thermostat"
#define SKETCH_VERSION "1.1"

#define CHILD_ID_HVAC    0 // S_HVAC
#define CHILD_ID_STATE   1 // S_LIGHT

// Declare Constants and Pin Numbers
#define SSerialRX        5  //Serial Receive pin 8
#define SSerialTX        3  //Serial Transmit pin 7

#define SSerialTxControl 4  //RS485 Direction control

#define RS485Transmit    HIGH
#define RS485Receive     LOW

// Declare objects
SoftwareSerial RS485Serial(SSerialRX, SSerialTX); // RX, TX

MySensor gw;

// Sensor values
MyMessage msgStatus ( CHILD_ID_STATE,  V_LIGHT );
MyMessage msgTemp   ( CHILD_ID_HVAC,   V_TEMP );
MyMessage msgSetCool( CHILD_ID_HVAC,   V_HVAC_SETPOINT_COOL );
MyMessage msgSetHeat( CHILD_ID_HVAC,   V_HVAC_SETPOINT_HEAT );

// Declare Variables
int byteReceived;
int byteSend;
String rcvString;
String sndString;
//This is for storing the last command that was sent 
String lastSent;
//the last sent set point
String setPoint;

String mode;
//This is the RS485 address of this node that gets sent to the thermostat
String serialAddr = "1";
//Placeholder for the last command sent
String LastSent = "";

void setup() {
  Serial.begin(9600);
  
  gw.begin( incomingMessage, AUTO, false );
  
  gw.sendSketchInfo( SKETCH_NAME, SKETCH_VERSION );
  
  // Register the thermostat with the gateway
  gw.present( CHILD_ID_HVAC,  S_HVAC );
  gw.present( CHILD_ID_STATE, S_LIGHT );
  
  // put your setup code here, to run once:
  pinMode( SSerialTxControl, OUTPUT );
  digitalWrite( SSerialTxControl, RS485Receive );  // Init Transceiver
  
  // Start the software serial port, to another device
  RS485Serial.begin(9600);   // set the data rate
} //End setup

void loop() {
  String dataIn;
  
  if (RS485Serial.available()) {
    dataIn = RS485Serial.readStringUntil('\n');
    ParseReceived(dataIn);
  }
} //End loop

void ParseReceived(String Message) {
  String StatusData;
  //int Count;
  String StatusString;
  String Status;
  String Type;
  String Value;

  int Index;
  int Start;
  int End;
  int StatIndex;

  Index = Message.indexOf(' ');
  Start = 0;
  
  Serial.println("Message: " + Message);
  
  if (Message.startsWith("A=")) {
    while (End != Message.length()) {
      End = (Index == -1) ? Message.length() : Index;
      //Get the status string to process
      StatusString = Message.substring(Start, End);
      //Change our start position to 1 over the last space found
      Start = Index + 1;
      //Find the end of the next status string
      Index = Message.indexOf(' ', Start);
  
      //Now we need to process the status string into it's Type and Value
      StatIndex = StatusString.indexOf('=');
      Type = StatusString.substring(0, StatIndex);
      Value = StatusString.substring(StatIndex + 1);
      ParseStatus(Type, Value);
    } 
  } else {
    SendCmd(LastSent);
  }
} //End ParseReceived

void ParseStatus(String Type, String Value) {
  //
  
  if (Type == "OA") {
      //Outside Air not used
  } else if (Type == "Z") {
      //Zone not used
  } else if (Type == "T") {
      Serial.println("T: " + Value);
      gw.send(msgTemp.set( F2C( Value.toFloat() ), 2 ));
  } else if (Type == "SP") {
      Serial.println("SP: " + Value);
      gw.send(msgSetCool.set( F2C( Value.toFloat() ), 2 ));
  } else if (Type == "SPH") {
      Serial.println("SPH: " + Value);
      gw.send(msgSetHeat.set( F2C( Value.toFloat() ), 2 ));
  } else if (Type == "SPC") {
      Serial.println("SPC: " + Value);
      gw.send(msgSetCool.set( F2C( Value.toFloat() ), 2 ));
  } else if (Type == "M") {
      //Serial.println("M: " + Value);
      //gw.send(msgFlowMode.set(Value.c_str()));
  } else if (Type == "FM") {
      //Serial.println("FM: " + Value);
      //gw.send(msgFlowMode.set(Value.c_str()));
    //Type 2 status message types
  } else if (Type == "H1A") {
      Serial.println("H1A: " + Value);
      if (Value == "1") {
        //gw.send(msgHvacSpeed.set("Min"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "H2A") {
      Serial.println("H2A: " + Value);
      if (Value == "1") {
        //gw.send(msgHvacSpeed.set("Normal"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "H3A") {
      Serial.println("H3A: " + Value);
      if (Value == "1") {
        //gw.send(msgHvacSpeed.set("Max"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "C1A") {
      Serial.println("C1A: " + Value);
      if (Value == "1") {
        //gw.send(msgHvacSpeed.set("Min"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "C2A") {
      Serial.println("C2A: " + Value);
      if (Value == "1") {
        //gw.send(msgHvacSpeed.set("Normal"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "FA") {
      Serial.println("FA: " + Value);
      if (Value == "1") {
        //gw.send(msgFlowMode.set("ContinuousOn"));
      } else {
        //gw.send(msgHvacSpeed.set("Auto"));
      }
  } else if (Type == "VA") {
      //Vent damper not used
  } else if (Type == "D1") {
      //Damper #1 not used
  } else if (Type == "SCP") {
      String stg1 = Value.substring(0, 1);
      String stg2 = Value.substring(0, Value.length() - 1);

      //logging.AddToLog("MOT/MRT stage 1: " & stg1, True)
      //Deal with minimum off time and minimum run times 
      //for stage 1

      //logging.AddToLog("MOT/MRT stage 2: " & stg2, True)
      //Deal with minimum off time and minimum run times 
      //for stage 2
  } else if (Type == "SM") {
      //logging.AddToLog("System mode: " & Value, True)
      String FlowState;
      
      if (Value == "O") {
        FlowState = "Off";
      } else if (Value == "H") {
        FlowState = "HeatOn";
      } else if (Value == "C") {
        FlowState = "CoolOn";
      } else {
        FlowState = "AutoChangeOver";
      }
      //Serial.println("SM: " + FlowState);
      //gw.send(msgFlowState.set(FlowState.c_str()));
  } else if (Type == "SF") {
      //logging.AddToLog("System fan: " & Value, True) 
      Serial.println("SF: " + Value);
      gw.send(msgStatus.set(Value.toInt()));
  }
} //End ParseStatus

float F2C(float Fahrenheit) {
  return (5.0f/9.0f) * (Fahrenheit-32);
} //End F2C

float C2F(float Celsius) {
  return (Celsius * 9.0f) / 5.0f + 32.0f;
} //End C2F

void SendCmd(String cmd) {
  String commandStr;
  commandStr = "A=" + serialAddr + " O=00 " + cmd;

  Serial.println("Writing to serial port: " + commandStr);
  
  // Enable RS485 Transmit only for the duration of the send
  digitalWrite(SSerialTxControl, RS485Transmit);
  RS485Serial.print(commandStr + "\r");
  LastSent = cmd;
  //Return to RS485 receive mode  
  digitalWrite(SSerialTxControl, RS485Receive);
} //End SendCmd

/**
 * incomingMessage - Process the incoming messages.
 */
void incomingMessage(const MyMessage &message) {
  Serial.println("message received");//String(message.type));
  //Serial.println(message.data);
  // We only expect one type of message from controller. But we better check anyway.
  if (message.isAck()) {
     Serial.println("This is an ack from gateway");
  }
  Serial.println("Temp: " + String(message.data) + " -- " + message.type);
  
  if ( message.type == V_TEMP ) {
    //
    Serial.println("Temp: " + String(message.data)); 
  } //End V_TEMP
  
  if ( message.type == V_STATUS ) {
    //
    Serial.println("Status: " + String(message.data)); 
  } //End V_STATUS
  
  if ( message.type == V_HVAC_FLOW_STATE ) {
    //
    Serial.println("Flow State: " + String(message.data)); 
  } //End V_HVAC_FLOW_STATE
  
  if ( message.type == V_HVAC_SPEED ) {
    //
    Serial.println("Speed: " + String(message.data)); 
  } //End V_HVAC_SPEED

  if (message.type == V_HVAC_SETPOINT_COOL) {
     Serial.println("Message received");
     String setPoint = String(C2F(atoi(message.data)));
     Serial.println("New Set Temp is : " + String(setPoint));
     SendCmd("SPC=" + setPoint + " R=1");
    
     // Write some debug info
     Serial.print("Incoming change for sensor:");
     Serial.print(message.sensor);
     Serial.print(", New status: ");
     Serial.println(message.data);
  } //End V_HVAC_SETPOINT_COOL

  if (message.type == V_HVAC_SETPOINT_HEAT) {
     Serial.println("Message received");
     String setPoint = String(C2F(atoi(message.data))); //.toInt();
     Serial.println("New Set Temp is : " + String(setPoint));
     SendCmd("SPH=" + setPoint + " R=1");
    
     // Write some debug info
     Serial.print("Incoming change for sensor:");
     Serial.print(message.sensor);
     Serial.print(", New status: ");
     Serial.println(message.data);
  } //End V_HVAC_SETPOINT_HEAT
  
  if ( (message.type == V_HVAC_FLOW_MODE) ) {
    //
    Serial.println("Flow Mode: " + String(message.data)); 
  } //End V_HVAC_FLOW_MODE
} //End incomingMessage

Thanks

[AWI]

@dbemowsk What does the serial log of the node tell you? Does it show messages coming in?

[AWI]

@dbemowsk And... (sorry to bother you with things you didn't ask for) Your sketch is loaded with String object definitions and therefore open fora lot of problems. String looks like an easy solution but not really suited for real time (MySensors) purposes.
An interesting article/ opinion background on the subject...

My advice: Forget about String and get back to comprehensible char arrays. (unless somebody can convince me otherwise) .

[dbemowsk]

@AWI said:

@dbemowsk What does the serial log of the node tell you? Does it show messages coming in?

I put the first Serial.println in the incomingMessage function to test and see if it was even hitting that function. I am not even seeing that in the serial monitor. That was the thing that prompted me to post this.

The set-up I have for testing right now is I have my node connected to the FTDI usb cable on one end (COM5). On the RS485 end (COM10) I have it looped back to my laptop through a USB to RS485 adapter. I then use a serial terminal program to transmit and receive strings similar to what would come from my thermostat. As I mentioned in my post, if I send a command on the RS485 side as if my thermostat controller sent it, it goes through ParseReceived and ParseStatus normally and the gw.send commands push it to Domoticz just fine.

I just can't think of any reason why the incoming messages from Domoticz are not being seen by the node. One thing I did find strange was that in order to see the Serial.println messages in the arduino serial monitor, I have it set to a baud of 115200 bps. The thing that confused me was that I have the first line in set-up as :

Serial.begin(9600);

I did this because that is the baud rate that my thermostat communicates at on the RS485 side of things. I realize that this is for the RS232 serial side on the arduino which is why I was confused.

[dbemowsk]

@AWI said:

@dbemowsk And... (sorry to bother you with things you didn't ask for) Your sketch is loaded with String object definitions and therefore open fora lot of problems. String looks like an easy solution but not really suited for real time (MySensors) purposes.
An interesting article/ opinion background on the subject...

My advice: Forget about String and get back to comprehensible char arrays. (unless somebody can convince me otherwise) .

No need to appologize. C and C++ are languages that I have not done much programming in. Well, a very limited amount of C++ and I have never used C (until getting into arduino which seems to be more C based). As I have been working in my arduuino stuff I have been seeing more people using char and char* definitions. That and converting to these using c_str(). As mentioned, I am new to these languages, so if you know of any good tutorials on how to use these versus String, I am open to suggestions. I have not yet looked at the link you posted, but will shortly. If this is the more proper way to do things in arduino, I would like to shift my thinking in that direction.

[dbemowsk]

@awi I am part way through your article on strings describing the stack and the heap. GREAT article. I have not finished it yet, but what I have read so far is excellent info.

[dbemowsk]

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