// Connect Uno via rs232 shield to Midnite Classic's rj11 MNGP/Slave rs232 port. // uses Modbus RTU to retrieve modbus registers. UNO is master, Classic is slave. // David Dix Jan 2015, dgd@kc.net.nz // 4X20lcd PID Timer1 Will Eert July2015, willeert@gmail.com #include //pwm frequency control #include //lcd #include //lcd #include //rs232 #include //pid int controlPin = 10; //pwm pin double divSpt=0; //pid storage for diversion setpoint for pid SP double battInput=0; //pid storage for battery volts for pid input float outputCalc = 0; // pid storage for output % calculation //pid Define Variables we'll be connecting to double Setpoint; double Input; double Output; //pid Specify the links and initial tuning parameters double Kp=400, Ki=75, Kd=.5; // change Kp,Ki&Kd to tune controller response PID myPID(&Input, &Output, &Setpoint, Kp, Ki, Kd, REVERSE); //rs232 Port information #define baud 19200 #define timeout 1000 #define polling 200 // the scan rate #define retry_count 10 #define TxEnablePin 2 // used to toggle the receive/transmit pin on the driver #define LED 9 enum { PACKET1, PACKET2, TOTAL_NO_OF_PACKETS // leave this last entry }; Packet packets[TOTAL_NO_OF_PACKETS]; // Create an array of Packets to be configured packetPointer packet1 = &packets[PACKET1]; packetPointer packet2 = &packets[PACKET2];// Create a packetPointer to access each packet unsigned int readRegsa[21]; unsigned int readRegsb[3]; LiquidCrystal_I2C lcd1(0X20,20,4); // set the LCD address to 0X20 for a 20 chars and 4 line display for lcd 1 LiquidCrystal_I2C lcd2(0X21,20,4); // set the LCD address to 0X20 for a 20 chars and 4 line display for lcd 2 void setup() { lcd1.init (); // lcd setUp LCD1 display lcd1.backlight (); lcd2.init (); //lcd setUp LCD2 display lcd2.backlight (); // rs 232 read 20 register starting at address 4114 modbus_construct(packet1, 10, READ_HOLDING_REGISTERS, 4114, 20, readRegsa); //rs232 read 2 register starting at address 4243 modbus_construct(packet2, 10, READ_HOLDING_REGISTERS, 4243, 2, readRegsb); // Initialize communication settings: modbus_configure(&Serial, baud, SERIAL_8N1, timeout, polling, retry_count, TxEnablePin, packets, TOTAL_NO_OF_PACKETS); { //pwm pin pinMode(controlPin,OUTPUT); //pid turn the PID on myPID.SetMode(MANUAL); myPID.SetOutputLimits(0,1023); //Timer1 allows the output limit to be 1023 Output = 0; Timer1.initialize(100000); //pwm frequency = 1000000/100000 = 10 hz. change () to alter frequency Timer1.pwm(controlPin,OUTPUT); } } void loop() { double batt_volts; int state ; double bat_v_spt,div_spt; // rs 232 read the Classic's modbus registers modbus_update(); // pid calculate rs232 battery voltage input value battInput = readRegsa[0]; battInput /=10; // pid calculate rs232 diversion voltage setpoint value divSpt = readRegsb[0]; divSpt /=10; divSpt -=.3; // pid change this number to adjust diversion setpoint offset from battery voltage setpoint //pid initialize the variables we're linked to Input = (battInput); Setpoint = (divSpt) ; // rs 232to lcd make Classic register values ready for LCD and diversion control state = (unsigned int)readRegsa[5] >> 8; // high byte contains charge state code bat_v_spt = readRegsb[0]; bat_v_spt /=10; // top line of lcd1 lcd1.setCursor(0,0); //lcd displays charge controller state on lcd1 switch (state) { case 0: lcd1.print ("Resting "); break; case 3: lcd1.print ("Absorb "); break; case 4: lcd1.print ("BulkMppt "); break; case 5: lcd1.print ("Float "); break; case 6: lcd1.print ("FloatMppt"); break; case 7: lcd1.print ("Equalize "); break; case 10: lcd1.print ("HyperVoc "); break; case 18: lcd1.print ("EqMppt "); break; } lcd2.setCursor (0,0); // 1st line lcd2 lcd2.print ("Divt Ctl State"); lcd2.setCursor (16,0); switch (state) // pid turns controller on/off in relation to Classic states manual = off automatic = on { case 0: //resting state { myPID.SetMode(MANUAL); //Manual when in resting Output = 0; // Output "locks" at existing when on manual. This drives output to zero lcd2.print ("Off"); // displays divt state } break; case 3: // absorb state { myPID.SetMode(AUTOMATIC); // Auto when in absorb lcd2.print (" On"); } break; case 4: //bulk state { myPID.SetMode(AUTOMATIC); //Auto when in bulk Output = 0; lcd2.print (" On"); } break; case 5: //float state { myPID.SetMode(AUTOMATIC); //Auto when in float lcd2.print (" On"); } break; case 6: //float mppt state { myPID.SetMode(AUTOMATIC); //Auto when in float mppt lcd2.print (" On"); } break; case 7: //equalize state { myPID.SetMode(AUTOMATIC); //Auto when in equaliize lcd2.print (" On"); } break; case 10: // hypervoc state { myPID.SetMode(MANUAL); //Manual when in hypervoc Output = 0; lcd2.print ("Off"); } break; case 18: //equalize mppt state { myPID.SetMode(AUTOMATIC); //Auto when in equalize mppt lcd2.print (" On"); } break; } //lcd1 lines 2,3&4 lcd1.setCursor (0,1); lcd1.print("Batt Volts ") ; lcd1.print((battInput)); lcd1.setCursor(0,2); lcd1.print("Batt V SetPt "); lcd1.print(bat_v_spt); lcd1.setCursor(0,3); lcd1.print("Divt V SetPt "); lcd1.print((divSpt)); lcd2.setCursor (0,1); // 2nd line lcd2 lcd2.print("Divt Output % "); lcd2.setCursor(14,1); lcd2.print(outputCalc); delay (300); // delay to stop LCD flickering, refreshes display 300ms Input = (battInput); myPID.Compute(); Timer1.setPwmDuty(controlPin,(int) Output); outputCalc =(Output) /=1023; // convert controller output to % outputCalc *=100; }