boiler.c

00001 #include <string.h>
00002 #include <stdint.h>
00003 #include <stdbool.h>
00004 
00005 #include "gpio.h"
00006 #include "mstimer.h"
00007 #include "ds18b20.h"
00008 #include "settings.h"
00009 #include "pwm.h"
00010 #include "log.h"
00011 
00012 #define BOILER_PUMP_DIR FIO2DIR(4) // P2.4 == p22
00013 #define BOILER_PUMP_PIN FIO2PIN(4)
00014 #define BOILER_PUMP_SET FIO2SET(4)
00015 #define BOILER_PUMP_CLR FIO2CLR(4)
00016 
00017 #define BOILER_CALL_DIR FIO2DIR(5) // P2.5 == p21
00018 #define BOILER_CALL_PIN FIO2PIN(5)
00019 #define BOILER_CALL_SET FIO2SET(5)
00020 #define BOILER_CALL_CLR FIO2CLR(5)
00021 
00022 #define PUMP_SPEED_CALLING_AUTO_ONLY  -1
00023 #define PUMP_SPEED_CALLING_AUTO_TWEAK -2
00024 
00025 #define MAX_SPEED 100
00026 
00027 static char*     tankRom;
00028 static char*   outputRom;
00029 static char*   returnRom;
00030 
00031 static int8_t  fullSpeedSecs;
00032 
00033 static int8_t  tankSetPoint;
00034 static int16_t tankHysteresis;
00035 static int16_t _runOnDelta16ths;
00036 static uint8_t runOnTime2s;
00037 
00038 static int8_t  pumpSpeedCalling;
00039 static int8_t  _rampDownTime;
00040 static int8_t  boilerTarget;
00041 
00042 static int8_t  _minSpeed;
00043 static int8_t  _midSpeedPwm;
00044 static int16_t _fullSpeedDeltaT16ths;
00045 
00046 //Set in main scan
00047 static int16_t _boilerOutput16ths   = DS18B20_ERROR_VALUE_NOT_SET;
00048 static int16_t _boilerReturn16ths   = DS18B20_ERROR_VALUE_NOT_SET;
00049 static int16_t _boilerRtnDel16ths   = DS18B20_ERROR_VALUE_NOT_SET;
00050 static int16_t _boilerDeltaT16ths   = DS18B20_ERROR_VALUE_NOT_SET;
00051 static bool    _boilerDeltaTisValid = false;
00052 
00053 int16_t  BoilerGetTankDS18B20Value  () { return DS18B20ValueFromRom(tankRom);   } 
00054 int16_t  BoilerGetOutputDS18B20Value() { return _boilerOutput16ths;    } 
00055 int16_t  BoilerGetReturnDS18B20Value() { return _boilerReturn16ths;    }
00056 int16_t  BoilerGetRtnDelDS18B20Value() { return _boilerRtnDel16ths;    }
00057 int16_t  BoilerGetDeltaTDS18B20Value() { return _boilerDeltaT16ths;    } 
00058 int      BoilerGetFullSpeedSecs     () { return fullSpeedSecs;         }
00059 int      BoilerGetTankSetPoint      () { return tankSetPoint;          }
00060 int      BoilerGetTankHysteresis    () { return tankHysteresis;        } 
00061 int      BoilerGetRunOnDeltaT       () { return _runOnDelta16ths;      }
00062 int      BoilerGetRunOnTime         () { return runOnTime2s << 1;      }
00063 int      BoilerGetPumpSpeedCalling  () { return pumpSpeedCalling;      }
00064 int      BoilerGetRampDownTime      () { return _rampDownTime;         }
00065 int      BoilerGetOutputTarget      () { return boilerTarget;          }
00066 int      BoilerGetMinSpeed          () { return _minSpeed;             }
00067 int      BoilerGetMidSpeedPwm       () { return _midSpeedPwm;          }
00068 int      BoilerGetFullSpeedDeltaT   () { return _fullSpeedDeltaT16ths; }
00069 
00070 static void setTankRom          (char* value) { memcpy(  tankRom,       value, 8);  SetTankRom               (   tankRom            ); }
00071 static void setOutputRom        (char* value) { memcpy(outputRom,       value, 8);  SetOutputRom             ( outputRom            ); }
00072 static void setReturnRom        (char* value) { memcpy(returnRom,       value, 8);  SetReturnRom             ( returnRom            ); }
00073 void BoilerSetFullSpeedSecs     (int   value) { fullSpeedSecs         = value;      SetBoilerFullSpeedSecs   (&fullSpeedSecs        ); }
00074 void BoilerSetTankSetPoint      (int   value) { tankSetPoint          = value;      SetTankSetPoint          (&tankSetPoint         ); }
00075 void BoilerSetTankHysteresis    (int   value) { tankHysteresis        = value;      SetTankHysteresis        (&tankHysteresis       ); }
00076 void BoilerSetRunOnDeltaT       (int   value) { _runOnDelta16ths      = value;      SetBoilerRunOnDeltaT     (&_runOnDelta16ths     ); }
00077 void BoilerSetRunOnTime         (int   value) { runOnTime2s           = value >> 1; SetBoilerRunOnTime2s     (&runOnTime2s          ); }
00078 void BoilerSetPumpSpeedCalling  (int   value) { pumpSpeedCalling      = value;      SetBoilerPumpSpeedCalling(&pumpSpeedCalling     ); }
00079 void BoilerSetRampDownTime      (int   value) { _rampDownTime         = value;      SetBoilerRampDownTime    (&_rampDownTime        ); }
00080 void BoilerSetOutputTarget      (int   value) { boilerTarget          = value;      SetBoilerTarget          (&boilerTarget         ); }
00081 void BoilerSetMinSpeed          (int   value) { _minSpeed             = value;      SetBoilerMinSpeed        (&_minSpeed            ); }
00082 void BoilerSetMidSpeedPwm       (int   value) { _midSpeedPwm          = value;      SetBoilerMidSpeedPwm     (&_midSpeedPwm         ); }
00083 void BoilerSetFullSpeedDeltaT   (int   value) { _fullSpeedDeltaT16ths = value;      SetBoilerFullSpeedDeltaT (&_fullSpeedDeltaT16ths); }
00084 
00085 static int calculateBetweenTwoPoints(int x, int xA, int xB, int yA, int yB)
00086 {
00087     float m = (float)(yB - yA) / (xB - xA);
00088     return  yA + m * (x - xA);
00089 }
00090 static int calculateSpeedFromDeltaT(int deltaT16ths)
00091 {
00092     if (deltaT16ths < _fullSpeedDeltaT16ths) return MAX_SPEED;   //Needed in case deltaT16ths is negative or zero
00093     int speed = MAX_SPEED * _fullSpeedDeltaT16ths / deltaT16ths; //eg for 20 deg ==> 100 * (10 << 4) / (20 << 4) == 50
00094     if (speed > MAX_SPEED) speed = MAX_SPEED;
00095     if (speed < _minSpeed) speed = _minSpeed;
00096     return speed;
00097 }
00098 static int calculateDeltaTFromSpeed(int speed)
00099 {
00100     int deltaT16ths = MAX_SPEED * _fullSpeedDeltaT16ths / speed; //eg for speed = 50 ==> 100 * (10 << 4) / 50 == 20 << 4
00101     return deltaT16ths;
00102 }
00103 
00104 int BoilerInit()
00105 {
00106       tankRom = DS18B20Roms + 8 * DS18B20RomCount;
00107     DS18B20RomSetters[DS18B20RomCount] = setTankRom;
00108     DS18B20RomNames[DS18B20RomCount] = "Tank";
00109     DS18B20RomCount++;
00110     
00111     outputRom = DS18B20Roms + 8 * DS18B20RomCount;
00112     DS18B20RomSetters[DS18B20RomCount] = setOutputRom;
00113     DS18B20RomNames[DS18B20RomCount] = "BlrOut";
00114     DS18B20RomCount++;
00115     
00116     returnRom = DS18B20Roms + 8 * DS18B20RomCount;
00117     DS18B20RomSetters[DS18B20RomCount] = setReturnRom;
00118     DS18B20RomNames[DS18B20RomCount] = "BlrRtn";
00119     DS18B20RomCount++;
00120     
00121     int address;
00122     uint8_t def1;
00123     int16_t def2;
00124     int32_t def4;
00125     GetTankRom               (   tankRom            );
00126     GetOutputRom             ( outputRom            );
00127     GetReturnRom             ( returnRom            );
00128     GetBoilerFullSpeedSecs   (&fullSpeedSecs        );
00129     GetTankSetPoint          (&tankSetPoint         );
00130     GetTankHysteresis        (&tankHysteresis       );
00131     GetBoilerRunOnDeltaT     (&_runOnDelta16ths     );
00132     GetBoilerRunOnTime2s     (&runOnTime2s          );
00133     GetBoilerPumpSpeedCalling(&pumpSpeedCalling     );
00134     GetBoilerRampDownTime    (&_rampDownTime        );
00135     GetBoilerTarget          (&boilerTarget         );
00136     GetBoilerMinSpeed        (&_minSpeed            );
00137     GetBoilerMidSpeedPwm     (&_midSpeedPwm         );
00138     GetBoilerFullSpeedDeltaT (&_fullSpeedDeltaT16ths);
00139     
00140     BOILER_PUMP_DIR = 1; //Set the direction to 1 == output
00141     BOILER_CALL_DIR = 1; //Set the direction to 1 == output
00142 
00143     PwmInit(400, 100);
00144 
00145     return 0;
00146 }
00147 bool BoilerCallEnable = true;
00148 bool BoilerCall = false;
00149 static void controlBoilerCall()
00150 {
00151     if (BoilerCallEnable)
00152     {
00153         int tankTemp16ths = DS18B20ValueFromRom(tankRom);
00154         if (DS18B20IsValidValue(tankTemp16ths)) //Ignore values which are likely to be wrong
00155         {
00156             int  tankUpper16ths = tankSetPoint   << 4;
00157             int hysteresis16ths = tankHysteresis << 4;
00158             int  tankLower16ths = tankUpper16ths - hysteresis16ths;
00159         
00160             if (tankTemp16ths >= tankUpper16ths) BoilerCall = false;
00161             if (tankTemp16ths <= tankLower16ths) BoilerCall = true;
00162         }
00163     }
00164     else
00165     {
00166         BoilerCall = false;
00167     }
00168 }
00169 bool BoilerPump = false;
00170 static void controlBoilerPump()
00171 {
00172     static uint32_t msTimerBoilerPumpRunOn = 0;
00173     if (BoilerCall)
00174     {
00175         BoilerPump = true;
00176         msTimerBoilerPumpRunOn = MsTimerCount;
00177     }
00178     else
00179     {
00180         if (MsTimerRelative(msTimerBoilerPumpRunOn,    runOnTime2s * 2000)) BoilerPump = false;
00181         if (_boilerDeltaTisValid && _boilerDeltaT16ths < _runOnDelta16ths ) BoilerPump = false;
00182     }
00183 }
00184 int BoilerPumpFlow  = MAX_SPEED;
00185 int BoilerPumpSpeed = MAX_SPEED;
00186 int BoilerPumpPwm   = 0;
00187 static int _autoSpeed = 0;
00188 static void calculateAutoSpeed()
00189 {
00190     if (!DS18B20IsValidValue(_boilerReturn16ths)) return;
00191     
00192     int target16ths = (int)boilerTarget << 4;
00193     int targetRise16ths = target16ths - _boilerReturn16ths; //eg 65 - eg 45 = 20*16 16ths
00194     
00195     _autoSpeed = calculateSpeedFromDeltaT(targetRise16ths);
00196 }
00197 static void controlBoilerPumpSpeed()
00198 {
00199     static uint32_t msTimerReduction = 0;
00200     calculateAutoSpeed();
00201     if (BoilerCall)
00202     {
00203         if (pumpSpeedCalling < 0) BoilerPumpSpeed = _autoSpeed;        //Auto
00204         else                      BoilerPumpSpeed = pumpSpeedCalling;  //Manual
00205         msTimerReduction = MsTimerCount;
00206     }
00207     else
00208     {
00209         if (BoilerPumpSpeed > _minSpeed)
00210         {
00211             int msPerUnit = 1000 * _rampDownTime / (MAX_SPEED - _minSpeed);
00212             if (MsTimerRepetitive(&msTimerReduction, msPerUnit)) BoilerPumpSpeed--;
00213         }
00214         else
00215         {
00216             BoilerPumpSpeed = _minSpeed;
00217         }
00218     }
00219     if (BoilerPumpSpeed < _minSpeed) BoilerPumpSpeed = _minSpeed;
00220     if (BoilerPumpSpeed > MAX_SPEED) BoilerPumpSpeed = MAX_SPEED;
00221 }
00222 static int speedToPwm(int speed)
00223 {
00224     #define MAX_SPEED_PWM 10
00225     #define MIN_SPEED_PWM 84
00226     /*
00227     PWM input signal [%] Pump status
00228     ≤ 10 Maximum speed
00229     > 10 / ≤ 84 Variable speed from minimum to maximum
00230     speed
00231     > 84 / ≤ 91 Minimum speed
00232     > 91/95 Hysteresis area: on/off
00233     > 95 / ≤ 100 Standby mode: off
00234     
00235     Max speed 100 is at fitted = 74; pwm = 10
00236     Min speed   0 is at fitted =  0; pwm = 84
00237     */
00238     if (speed <= _minSpeed) return MIN_SPEED_PWM;
00239     if (speed >= MAX_SPEED) return MAX_SPEED_PWM;
00240     int midSpeed = (_minSpeed + MAX_SPEED) / 2;
00241     if (speed < midSpeed) return calculateBetweenTwoPoints(speed, _minSpeed,  midSpeed, MIN_SPEED_PWM,   _midSpeedPwm);
00242     else                  return calculateBetweenTwoPoints(speed,  midSpeed, MAX_SPEED,  _midSpeedPwm,  MAX_SPEED_PWM);
00243     //int pwm = calculateBetweenTwoPoints(BoilerPumpSpeed, _minSpeed, MAX_SPEED, 84, 10);
00244     //if (pwm < 10) pwm = 10;
00245     //if (pwm > 84) pwm = 84;
00246     //BoilerPumpPwm = pwm;
00247 }
00248 #define TIME_BEFORE_TWEAK_SECS 120
00249 static void tweakDeltaTs()
00250 {
00251     if (pumpSpeedCalling != PUMP_SPEED_CALLING_AUTO_TWEAK) return;
00252     
00253     static uint32_t msTimerBoilerHeating = 0;
00254     if (!BoilerCall) msTimerBoilerHeating = MsTimerCount;
00255     if (!MsTimerRelative(msTimerBoilerHeating, TIME_BEFORE_TWEAK_SECS * 1000)) return;
00256     
00257     if (!_boilerDeltaTisValid) return;
00258     
00259     static int speedLastScan = -1;
00260     
00261     if (speedLastScan < MAX_SPEED && BoilerPumpSpeed == MAX_SPEED)
00262     {
00263         if (_fullSpeedDeltaT16ths > _boilerDeltaT16ths) _fullSpeedDeltaT16ths--;
00264         if (_fullSpeedDeltaT16ths < _boilerDeltaT16ths) _fullSpeedDeltaT16ths++;
00265     }
00266     
00267     speedLastScan = BoilerPumpSpeed;
00268 }
00269 
00270 #define TIME_BEFORE_DELTA_T_ALARM_SECS 300
00271 #define DELTA_T_LIMIT 3
00272 static void checkDeltaTs()
00273 {   
00274     static uint32_t msTimerDeltaTNonConform = 0;
00275     if (!BoilerCall)
00276     {
00277         msTimerDeltaTNonConform = MsTimerCount;
00278         return;
00279     }
00280     
00281     int expectedDeltaT16ths = calculateDeltaTFromSpeed(BoilerPumpSpeed);
00282     
00283     bool deltaTisOk = _boilerDeltaTisValid &&
00284                       _boilerDeltaT16ths > (expectedDeltaT16ths - (DELTA_T_LIMIT << 4)) &&
00285                       _boilerDeltaT16ths < (expectedDeltaT16ths + (DELTA_T_LIMIT << 4));
00286     
00287     static bool hadAlarm = false;
00288     if (deltaTisOk) msTimerDeltaTNonConform = MsTimerCount;
00289     bool haveAlarm = MsTimerRelative(msTimerDeltaTNonConform, TIME_BEFORE_DELTA_T_ALARM_SECS * 1000);
00290     if (haveAlarm && !hadAlarm)
00291     {
00292         //BoilerCallEnable = false;
00293         LogTimeF("Boiler disabled - delta T was outside %d degree window for %d seconds", DELTA_T_LIMIT, TIME_BEFORE_DELTA_T_ALARM_SECS);
00294         Log(": actual ");
00295         DS18B20Log(_boilerDeltaT16ths);
00296         Log(", expected ");
00297         DS18B20Log(expectedDeltaT16ths);
00298         Log("\r\n");
00299     }
00300     hadAlarm = haveAlarm;
00301 }
00302 #define NUMBER_OF_STEPS 10
00303 static int16_t _returns16ths[NUMBER_OF_STEPS]; //0 is last, 9th is first
00304 static void delayLine()
00305 {
00306     static uint32_t msTimerDelay = 0;
00307     if (BoilerPump)
00308     {
00309         int msTotal = 1000 * fullSpeedSecs * MAX_SPEED / BoilerPumpSpeed; //speed 10 ==> 10000; speed 100 ==> 1000
00310         int msPerStep = msTotal / NUMBER_OF_STEPS;
00311         if (MsTimerRelative(msTimerDelay, msPerStep))
00312         {
00313             for (int i = 0; i < NUMBER_OF_STEPS - 1; i++) _returns16ths[i] = _returns16ths[i + 1];
00314             _returns16ths[NUMBER_OF_STEPS - 1] = _boilerReturn16ths;
00315             msTimerDelay = MsTimerCount;
00316             //LogTimeF("Ms per step = %d, delayed boiler return = ", msPerStep);
00317             //DS18B20Log(_returns16ths[0]);
00318             //Log("\r\n");
00319         }
00320     }
00321     else
00322     {
00323         msTimerDelay = MsTimerCount;
00324         for (int i = 0; i < NUMBER_OF_STEPS; i++) _returns16ths[i] = DS18B20_ERROR_VALUE_NOT_SET;
00325     }
00326 }
00327 
00328 void BoilerMain()
00329 {
00330     delayLine();
00331     _boilerOutput16ths   = DS18B20ValueFromRom(outputRom);
00332     _boilerReturn16ths   = DS18B20ValueFromRom(returnRom);
00333     _boilerRtnDel16ths   = _returns16ths[0];
00334     _boilerDeltaTisValid = DS18B20IsValidValue(_boilerOutput16ths) && DS18B20IsValidValue(_boilerRtnDel16ths);
00335     if (_boilerDeltaTisValid) _boilerDeltaT16ths   = _boilerOutput16ths - _boilerRtnDel16ths;
00336     else                      _boilerDeltaT16ths   = DS18B20_ERROR_VALUE_NOT_SET;
00337     
00338     controlBoilerCall();
00339     if (BoilerCall) BOILER_CALL_SET;
00340     else            BOILER_CALL_CLR;
00341     
00342     controlBoilerPump();
00343     if (BoilerPump) BOILER_PUMP_SET;
00344     else            BOILER_PUMP_CLR;
00345     
00346     controlBoilerPumpSpeed();
00347     BoilerPumpPwm = speedToPwm(BoilerPumpSpeed);
00348     PwmSet(BoilerPumpPwm);
00349     
00350     tweakDeltaTs();
00351     checkDeltaTs();
00352 }