src/modules/tools/temperaturecontrol/TemperatureControl.cpp

   1 /*
   2       This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
   3       Smoothie is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
   4       Smoothie is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   5       You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
   6 */
   7
   8 // TODO : THIS FILE IS LAME, MUST BE MADE MUCH BETTER
   9
  10 #include "libs/Module.h"
  11 #include "libs/Kernel.h"
  12 #include <math.h>
  13 #include "TemperatureControl.h"
  14 #include "TemperatureControlPool.h"
  15 #include "libs/Pin.h"
  16 #include "modules/robot/Conveyor.h"
  17 #include "PublicDataRequest.h"
  18
  19 #include "PublicData.h"
  20 #include "ToolManagerPublicAccess.h"
  21 #include "StreamOutputPool.h"
  22 #include "Config.h"
  23 #include "checksumm.h"
  24 #include "Gcode.h"
  25 #include "SlowTicker.h"
  26 #include "ConfigValue.h"
  27 #include "PID_Autotuner.h"
  28 #include "SerialMessage.h"
  29 #include "utils.h"
  30
  31 // Temp sensor implementations:
  32 #include "Thermistor.h"
  33 #include "max31855.h"
  34 #include "AD8495.h"
  35
  36 #include "MRI_Hooks.h"
  37
  38 #define UNDEFINED -1
  39
  40 #define sensor_checksum                    CHECKSUM("sensor")
  41
  42 #define readings_per_second_checksum       CHECKSUM("readings_per_second")
  43 #define max_pwm_checksum                   CHECKSUM("max_pwm")
  44 #define pwm_frequency_checksum             CHECKSUM("pwm_frequency")
  45 #define bang_bang_checksum                 CHECKSUM("bang_bang")
  46 #define hysteresis_checksum                CHECKSUM("hysteresis")
  47 #define heater_pin_checksum                CHECKSUM("heater_pin")
  48 #define max_temp_checksum                  CHECKSUM("max_temp")
  49 #define min_temp_checksum                  CHECKSUM("min_temp")
  50
  51 #define get_m_code_checksum                CHECKSUM("get_m_code")
  52 #define set_m_code_checksum                CHECKSUM("set_m_code")
  53 #define set_and_wait_m_code_checksum       CHECKSUM("set_and_wait_m_code")
  54
  55 #define designator_checksum                CHECKSUM("designator")
  56
  57 #define p_factor_checksum                  CHECKSUM("p_factor")
  58 #define i_factor_checksum                  CHECKSUM("i_factor")
  59 #define d_factor_checksum                  CHECKSUM("d_factor")
  60
  61 #define i_max_checksum                     CHECKSUM("i_max")
  62 #define windup_checksum                    CHECKSUM("windup")
  63
  64 #define preset1_checksum                   CHECKSUM("preset1")
  65 #define preset2_checksum                   CHECKSUM("preset2")
  66
  67 #define runaway_range_checksum             CHECKSUM("runaway_range")
  68 #define runaway_heating_timeout_checksum   CHECKSUM("runaway_heating_timeout")
  69
  70 TemperatureControl::TemperatureControl(uint16_t name, int index)
  71 {
  72     name_checksum= name;
  73     pool_index= index;
  74     waiting= false;
  75     temp_violated= false;
  76     sensor= nullptr;
  77     readonly= false;
  78 }
  79
  80 TemperatureControl::~TemperatureControl()
  81 {
  82     delete sensor;
  83 }
  84
  85 void TemperatureControl::on_module_loaded()
  86 {
  87
  88     // We start not desiring any temp
  89     this->target_temperature = UNDEFINED;
  90     this->sensor_settings= false; // set to true if sensor settings have been overriden
  91
  92     // Settings
  93     this->load_config();
  94
  95     // Register for events
  96     this->register_for_event(ON_GCODE_RECEIVED);
  97     this->register_for_event(ON_GET_PUBLIC_DATA);
  98
  99     if(!this->readonly) {
 100         this->register_for_event(ON_SECOND_TICK);
 101         this->register_for_event(ON_MAIN_LOOP);
 102         this->register_for_event(ON_SET_PUBLIC_DATA);
 103         this->register_for_event(ON_HALT);
 104     }
 105 }
 106
 107 void TemperatureControl::on_halt(void *arg)
 108 {
 109     if(arg == nullptr) {
 110         // turn off heater
 111         this->o = 0;
 112         this->heater_pin.set(0);
 113         this->target_temperature = UNDEFINED;
 114     }
 115 }
 116
 117 void TemperatureControl::on_main_loop(void *argument)
 118 {
 119     if (this->temp_violated) {
 120         this->temp_violated = false;
 121         THEKERNEL->streams->printf("ERROR : MINTEMP or MAXTEMP triggered on %s. Check your temperature sensors!\n", designator.c_str());
 122         THEKERNEL->streams->printf("HALT asserted - reset or M999 required\n");
 123         THEKERNEL->call_event(ON_HALT, nullptr);
 124     }
 125 }
 126
 127 // Get configuration from the config file
 128 void TemperatureControl::load_config()
 129 {
 130
 131     // General config
 132     this->set_m_code          = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, set_m_code_checksum)->by_default(104)->as_number();
 133     this->set_and_wait_m_code = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, set_and_wait_m_code_checksum)->by_default(109)->as_number();
 134     this->get_m_code          = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, get_m_code_checksum)->by_default(105)->as_number();
 135     this->readings_per_second = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, readings_per_second_checksum)->by_default(20)->as_number();
 136
 137     this->designator          = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, designator_checksum)->by_default(string("T"))->as_string();
 138
 139     // Runaway parameters
 140     this->runaway_range           = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, runaway_range_checksum)->by_default(0)->as_number();
 141     this->runaway_heating_timeout = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, runaway_heating_timeout_checksum)->by_default(0)->as_number();
 142
 143     // Max and min temperatures we are not allowed to get over (Safety)
 144     this->max_temp = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, max_temp_checksum)->by_default(300)->as_number();
 145     this->min_temp = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, min_temp_checksum)->by_default(0)->as_number();
 146
 147     // Heater pin
 148     this->heater_pin.from_string( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, heater_pin_checksum)->by_default("nc")->as_string());
 149     if(this->heater_pin.connected()){
 150         this->readonly= false;
 151         this->heater_pin.as_output();
 152
 153     } else {
 154         this->readonly= true;
 155     }
 156
 157     // For backward compatibility, default to a thermistor sensor.
 158     std::string sensor_type = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, sensor_checksum)->by_default("thermistor")->as_string();
 159
 160     // Instantiate correct sensor (TBD: TempSensor factory?)
 161     delete sensor;
 162     sensor = nullptr; // In case we fail to create a new sensor.
 163     if(sensor_type.compare("thermistor") == 0) {
 164         sensor = new Thermistor();
 165     } else if(sensor_type.compare("max31855") == 0) {
 166         sensor = new Max31855();
 167     } else if(sensor_type.compare("ad8495") == 0) {
 168         sensor = new AD8495();
 169     } else {
 170         sensor = new TempSensor(); // A dummy implementation
 171     }
 172     sensor->UpdateConfig(temperature_control_checksum, this->name_checksum);
 173
 174     this->preset1 = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, preset1_checksum)->by_default(0)->as_number();
 175     this->preset2 = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, preset2_checksum)->by_default(0)->as_number();
 176
 177
 178     // sigma-delta output modulation
 179     this->o = 0;
 180
 181     if(!this->readonly) {
 182         // used to enable bang bang control of heater
 183         this->use_bangbang = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, bang_bang_checksum)->by_default(false)->as_bool();
 184         this->hysteresis = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, hysteresis_checksum)->by_default(2)->as_number();
 185         this->windup = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, windup_checksum)->by_default(false)->as_bool();
 186         this->heater_pin.max_pwm( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, max_pwm_checksum)->by_default(255)->as_number() );
 187         this->heater_pin.set(0);
 188         set_low_on_debug(heater_pin.port_number, heater_pin.pin);
 189         // activate SD-DAC timer
 190         THEKERNEL->slow_ticker->attach( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, pwm_frequency_checksum)->by_default(2000)->as_number(), &heater_pin, &Pwm::on_tick);
 191     }
 192
 193
 194     // reading tick
 195     THEKERNEL->slow_ticker->attach( this->readings_per_second, this, &TemperatureControl::thermistor_read_tick );
 196     this->PIDdt = 1.0 / this->readings_per_second;
 197
 198     // PID
 199     setPIDp( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, p_factor_checksum)->by_default(10 )->as_number() );
 200     setPIDi( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, i_factor_checksum)->by_default(0.3f)->as_number() );
 201     setPIDd( THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, d_factor_checksum)->by_default(200)->as_number() );
 202
 203     if(!this->readonly) {
 204         // set to the same as max_pwm by default
 205         this->i_max = THEKERNEL->config->value(temperature_control_checksum, this->name_checksum, i_max_checksum   )->by_default(this->heater_pin.max_pwm())->as_number();
 206     }
 207
 208     this->iTerm = 0.0;
 209     this->lastInput = -1.0;
 210     this->last_reading = 0.0;
 211 }
 212
 213 void TemperatureControl::on_gcode_received(void *argument)
 214 {
 215     Gcode *gcode = static_cast<Gcode *>(argument);
 216     if (gcode->has_m) {
 217
 218         if( gcode->m == this->get_m_code ) {
 219             char buf[32]; // should be big enough for any status
 220             int n = snprintf(buf, sizeof(buf), "%s:%3.1f /%3.1f @%d ", this->designator.c_str(), this->get_temperature(), ((target_temperature <= 0) ? 0.0 : target_temperature), this->o);
 221             gcode->txt_after_ok.append(buf, n);
 222             return;
 223         }
 224
 225         if (gcode->m == 305) { // set or get sensor settings
 226             if (gcode->has_letter('S') && (gcode->get_value('S') == this->pool_index)) {
 227                 TempSensor::sensor_options_t args= gcode->get_args();
 228                 args.erase('S'); // don't include the S
 229                 if(args.size() > 0) {
 230                     // set the new options
 231                     if(sensor->set_optional(args)) {
 232                         this->sensor_settings= true;
 233                     }else{
 234                         gcode->stream->printf("Unable to properly set sensor settings, make sure you specify all required values\n");
 235                     }
 236                 }else{
 237                     // don't override
 238                     this->sensor_settings= false;
 239                 }
 240
 241             }else if(!gcode->has_letter('S')) {
 242                 gcode->stream->printf("%s(S%d): using %s\n", this->designator.c_str(), this->pool_index, this->readonly?"Readonly" : this->use_bangbang?"Bangbang":"PID");
 243                 sensor->get_raw();
 244                 TempSensor::sensor_options_t options;
 245                 if(sensor->get_optional(options)) {
 246                     for(auto &i : options) {
 247                         // foreach optional value
 248                         gcode->stream->printf("%s(S%d): %c %1.18f\n", this->designator.c_str(), this->pool_index, i.first, i.second);
 249                     }
 250                 }
 251             }
 252
 253             return;
 254         }
 255
 256         // readonly sensors don't handle the rest
 257         if(this->readonly) return;
 258
 259         if (gcode->m == 143) {
 260             if (gcode->has_letter('S') && (gcode->get_value('S') == this->pool_index)) {
 261                 if(gcode->has_letter('P')) {
 262                     max_temp= gcode->get_value('P');
 263
 264                 } else {
 265                     gcode->stream->printf("Nothing set NOTE Usage is M143 S0 P300 where <S> is the hotend index and <P> is the maximum temp to set\n");
 266                 }
 267
 268             }else if(gcode->get_num_args() == 0) {
 269                 gcode->stream->printf("Maximum temperature for %s(%d) is %f°C\n", this->designator.c_str(), this->pool_index, max_temp);
 270             }
 271
 272         } else if (gcode->m == 301) {
 273             if (gcode->has_letter('S') && (gcode->get_value('S') == this->pool_index)) {
 274                 if (gcode->has_letter('P'))
 275                     setPIDp( gcode->get_value('P') );
 276                 if (gcode->has_letter('I'))
 277                     setPIDi( gcode->get_value('I') );
 278                 if (gcode->has_letter('D'))
 279                     setPIDd( gcode->get_value('D') );
 280                 if (gcode->has_letter('X'))
 281                     this->i_max = gcode->get_value('X');
 282                 if (gcode->has_letter('Y'))
 283                     this->heater_pin.max_pwm(gcode->get_value('Y'));
 284
 285             }else if(!gcode->has_letter('S')) {
 286                 gcode->stream->printf("%s(S%d): Pf:%g If:%g Df:%g X(I_max):%g max pwm: %d O:%d\n", this->designator.c_str(), this->pool_index, this->p_factor, this->i_factor / this->PIDdt, this->d_factor * this->PIDdt, this->i_max, this->heater_pin.max_pwm(), o);
 287             }
 288
 289         } else if (gcode->m == 500 || gcode->m == 503) { // M500 saves some volatile settings to config override file, M503 just prints the settings
 290             gcode->stream->printf(";PID settings:\nM301 S%d P%1.4f I%1.4f D%1.4f X%1.4f Y%d\n", this->pool_index, this->p_factor, this->i_factor / this->PIDdt, this->d_factor * this->PIDdt, this->i_max, this->heater_pin.max_pwm());
 291
 292             gcode->stream->printf(";Max temperature setting:\nM143 S%d P%1.4f\n", this->pool_index, this->max_temp);
 293
 294             if(this->sensor_settings) {
 295                 // get or save any sensor specific optional values
 296                 TempSensor::sensor_options_t options;
 297                 if(sensor->get_optional(options) && !options.empty()) {
 298                     gcode->stream->printf(";Optional temp sensor specific settings:\nM305 S%d", this->pool_index);
 299                     for(auto &i : options) {
 300                         gcode->stream->printf(" %c%1.18f", i.first, i.second);
 301                     }
 302                     gcode->stream->printf("\n");
 303                 }
 304             }
 305
 306         } else if( ( gcode->m == this->set_m_code || gcode->m == this->set_and_wait_m_code ) && gcode->has_letter('S')) {
 307             // this only gets handled if it is not controlled by the tool manager or is active in the toolmanager
 308             this->active = true;
 309
 310             // this is safe as old configs as well as single extruder configs the toolmanager will not be running so will return false
 311             // this will also ignore anything that the tool manager is not controlling and return false, otherwise it returns the active tool
 312             void *returned_data;
 313             bool ok = PublicData::get_value( tool_manager_checksum, is_active_tool_checksum, this->name_checksum, &returned_data );
 314             if (ok) {
 315                 uint16_t active_tool_name =  *static_cast<uint16_t *>(returned_data);
 316                 this->active = (active_tool_name == this->name_checksum);
 317             }
 318
 319             if(this->active) {
 320                 // required so temp change happens in order
 321                 THEKERNEL->conveyor->wait_for_idle();
 322
 323                 float v = gcode->get_value('S');
 324
 325                 if (v == 0.0) {
 326                     this->target_temperature = UNDEFINED;
 327                     this->heater_pin.set((this->o = 0));
 328                 } else {
 329                     this->set_desired_temperature(v);
 330                     // wait for temp to be reached, no more gcodes will be fetched until this is complete
 331                     if( gcode->m == this->set_and_wait_m_code) {
 332                         if(isinf(get_temperature()) && isinf(sensor->get_temperature())) {
 333                             THEKERNEL->streams->printf("Temperature reading is unreliable on %s HALT asserted - reset or M999 required\n", designator.c_str());
 334                             THEKERNEL->call_event(ON_HALT, nullptr);
 335                             return;
 336                         }
 337
 338                         this->waiting = true; // on_second_tick will announce temps
 339                         while ( get_temperature() < target_temperature ) {
 340                             THEKERNEL->call_event(ON_IDLE, this);
 341                             // check if ON_HALT was called (usually by kill button)
 342                             if(THEKERNEL->is_halted() || this->target_temperature == UNDEFINED) {
 343                                 THEKERNEL->streams->printf("Wait on temperature aborted by kill\n");
 344                                 break;
 345                             }
 346                         }
 347                         this->waiting = false;
 348                     }
 349                 }
 350             }
 351         }
 352     }
 353 }
 354
 355 void TemperatureControl::on_get_public_data(void *argument)
 356 {
 357     PublicDataRequest *pdr = static_cast<PublicDataRequest *>(argument);
 358
 359     if(!pdr->starts_with(temperature_control_checksum)) return;
 360
 361     if(pdr->second_element_is(pool_index_checksum)) {
 362         // asking for our instance pointer if we have this pool_index
 363         if(pdr->third_element_is(this->pool_index)) {
 364             static void *return_data;
 365             return_data = this;
 366             pdr->set_data_ptr(&return_data);
 367             pdr->set_taken();
 368         }
 369
 370     }else if(pdr->second_element_is(poll_controls_checksum)) {
 371         // polling for all temperature controls
 372         // add our data to the list which is passed in via the data_ptr
 373
 374         std::vector<struct pad_temperature> *v= static_cast<std::vector<pad_temperature>*>(pdr->get_data_ptr());
 375
 376         struct pad_temperature t;
 377         // setup data
 378         t.current_temperature = this->get_temperature();
 379         t.target_temperature = (target_temperature <= 0) ? 0 : this->target_temperature;
 380         t.pwm = this->o;
 381         t.designator= this->designator;
 382         t.id= this->name_checksum;
 383         v->push_back(t);
 384         pdr->set_taken();
 385
 386     }else if(pdr->second_element_is(current_temperature_checksum)) {
 387         // if targeted at us
 388         if(pdr->third_element_is(this->name_checksum)) {
 389             // ok this is targeted at us, so set the requ3sted data in the pointer passed into us
 390             struct pad_temperature *t= static_cast<pad_temperature*>(pdr->get_data_ptr());
 391             t->current_temperature = this->get_temperature();
 392             t->target_temperature = (target_temperature <= 0) ? 0 : this->target_temperature;
 393             t->pwm = this->o;
 394             t->designator= this->designator;
 395             t->id= this->name_checksum;
 396             pdr->set_taken();
 397         }
 398     }
 399
 400 }
 401
 402 void TemperatureControl::on_set_public_data(void *argument)
 403 {
 404     PublicDataRequest *pdr = static_cast<PublicDataRequest *>(argument);
 405
 406     if(!pdr->starts_with(temperature_control_checksum)) return;
 407
 408     if(!pdr->second_element_is(this->name_checksum)) return;
 409
 410     // ok this is targeted at us, so set the temp
 411     // NOTE unlike the M code this will set the temp now not when the queue is empty
 412     float t = *static_cast<float *>(pdr->get_data_ptr());
 413     this->set_desired_temperature(t);
 414     pdr->set_taken();
 415 }
 416
 417 void TemperatureControl::set_desired_temperature(float desired_temperature)
 418 {
 419     // Never go over the configured max temperature
 420     if( desired_temperature > this->max_temp ){
 421         desired_temperature = this->max_temp;
 422     }
 423
 424     if (desired_temperature == 1.0F)
 425         desired_temperature = preset1;
 426     else if (desired_temperature == 2.0F)
 427         desired_temperature = preset2;
 428
 429     float last_target_temperature= target_temperature;
 430     target_temperature = desired_temperature;
 431     if (desired_temperature <= 0.0F){
 432         // turning it off
 433         heater_pin.set((this->o = 0));
 434
 435     }else if(last_target_temperature <= 0.0F) {
 436         // if it was off and we are now turning it on we need to initialize
 437         this->lastInput= last_reading;
 438         // set to whatever the output currently is See http://brettbeauregard.com/blog/2011/04/improving-the-beginner%E2%80%99s-pid-initialization/
 439         this->iTerm= this->o;
 440         if (this->iTerm > this->i_max) this->iTerm = this->i_max;
 441         else if (this->iTerm < 0.0) this->iTerm = 0.0;
 442     }
 443 }
 444
 445 float TemperatureControl::get_temperature()
 446 {
 447     return last_reading;
 448 }
 449
 450 uint32_t TemperatureControl::thermistor_read_tick(uint32_t dummy)
 451 {
 452     float temperature = sensor->get_temperature();
 453     if(!this->readonly && target_temperature > 2) {
 454         if (isinf(temperature) || temperature < min_temp || temperature > max_temp) {
 455             this->temp_violated = true;
 456             target_temperature = UNDEFINED;
 457             heater_pin.set((this->o = 0));
 458         } else {
 459             pid_process(temperature);
 460         }
 461     }
 462
 463     last_reading = temperature;
 464     return 0;
 465 }
 466
 467 /**
 468  * Based on https://github.com/br3ttb/Arduino-PID-Library
 469  */
 470 void TemperatureControl::pid_process(float temperature)
 471 {
 472     if(use_bangbang) {
 473         // bang bang is very simple, if temp is < target - hysteresis turn on full else if  temp is > target + hysteresis turn heater off
 474         // good for relays
 475         if(temperature > (target_temperature + hysteresis) && this->o > 0) {
 476             heater_pin.set(false);
 477             this->o = 0; // for display purposes only
 478
 479         } else if(temperature < (target_temperature - hysteresis) && this->o <= 0) {
 480             if(heater_pin.max_pwm() >= 255) {
 481                 // turn on full
 482                 this->heater_pin.set(true);
 483                 this->o = 255; // for display purposes only
 484             } else {
 485                 // only to whatever max pwm is configured
 486                 this->heater_pin.pwm(heater_pin.max_pwm());
 487                 this->o = heater_pin.max_pwm(); // for display purposes only
 488             }
 489         }
 490         return;
 491     }
 492
 493     // regular PID control
 494     float error = target_temperature - temperature;
 495
 496     float new_I = this->iTerm + (error * this->i_factor);
 497     if (new_I > this->i_max) new_I = this->i_max;
 498     else if (new_I < 0.0) new_I = 0.0;
 499     if(!this->windup) this->iTerm= new_I;
 500
 501     float d = (temperature - this->lastInput);
 502
 503     // calculate the PID output
 504     // TODO does this need to be scaled by max_pwm/256? I think not as p_factor already does that
 505     this->o = (this->p_factor * error) + new_I - (this->d_factor * d);
 506
 507     if (this->o >= heater_pin.max_pwm())
 508         this->o = heater_pin.max_pwm();
 509     else if (this->o < 0)
 510         this->o = 0;
 511     else if(this->windup)
 512         this->iTerm = new_I; // Only update I term when output is not saturated.
 513
 514     this->heater_pin.pwm(this->o);
 515     this->lastInput = temperature;
 516 }
 517
 518 void TemperatureControl::on_second_tick(void *argument)
 519 {
 520
 521     // If waiting for a temperature to be reach, display it to keep host programs up to date on the progress
 522     if (waiting)
 523         THEKERNEL->streams->printf("%s:%3.1f /%3.1f @%d\n", designator.c_str(), get_temperature(), ((target_temperature <= 0) ? 0.0 : target_temperature), o);
 524
 525     // Check whether or not there is a temperature runaway issue, if so stop everything and report it
 526     if(THEKERNEL->is_halted()) return;
 527
 528     if( this->target_temperature <= 0 ){ // If we are not trying to heat, state is NOT_HEATING
 529         this->runaway_state = NOT_HEATING;
 530     }else{
 531         switch( this->runaway_state ){
 532             case NOT_HEATING: // If we were previously not trying to heat, but we are now, change to state WAITING_FOR_TEMP_TO_BE_REACHED
 533                 if( this->target_temperature > 0 ){
 534                     this->runaway_state = WAITING_FOR_TEMP_TO_BE_REACHED;
 535                     this->runaway_heating_timer = 0;
 536                 }
 537                 break;
 538             case WAITING_FOR_TEMP_TO_BE_REACHED: // In we are in state 1 ( waiting for temperature to be reached ), and the temperature has been reached, change to state TARGET_TEMPERATURE_REACHED
 539                 if( this->get_temperature() >= this->target_temperature ){
 540                     this->runaway_state = TARGET_TEMPERATURE_REACHED;
 541                 }
 542                 this->runaway_heating_timer++;
 543                 if( this->runaway_heating_timer > this->runaway_heating_timeout && this->runaway_heating_timeout != 0 ){
 544                     this->runaway_heating_timer = 0;
 545                     THEKERNEL->streams->printf("ERROR : Temperature took too long to be reached on %s, HALT asserted, TURN POWER OFF IMMEDIATELY - reset or M999 required\n", designator.c_str());
 546                     THEKERNEL->call_event(ON_HALT, nullptr);
 547                 }
 548                 break;
 549             case TARGET_TEMPERATURE_REACHED: { // If we are in state TARGET_TEMPERATURE_REACHED, check for thermal runaway
 550                 float delta= this->get_temperature() - this->target_temperature;
 551                 // If the temperature is outside the acceptable range
 552                 if(this->runaway_range != 0 && fabsf(delta) > this->runaway_range){
 553                     THEKERNEL->streams->printf("ERROR : Temperature runaway on %s (delta temp %f), HALT asserted, TURN POWER OFF IMMEDIATELY - reset or M999 required\n", designator.c_str(), delta);
 554                     THEKERNEL->call_event(ON_HALT, nullptr);
 555                 }
 556             }
 557                 break;
 558         }
 559     }
 560 }
 561
 562 void TemperatureControl::setPIDp(float p)
 563 {
 564     this->p_factor = p;
 565 }
 566
 567 void TemperatureControl::setPIDi(float i)
 568 {
 569     this->i_factor = i * this->PIDdt;
 570 }
 571
 572 void TemperatureControl::setPIDd(float d)
 573 {
 574     this->d_factor = d / this->PIDdt;
 575 }