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 "libs/Pin.h"
  15
  16 TemperatureControl::TemperatureControl(){}
  17
  18 TemperatureControl::TemperatureControl(uint16_t name){
  19     this->name_checksum = name;
  20     this->error_count = 0;
  21     this->waiting = false;
  22 }
  23
  24 void TemperatureControl::on_module_loaded(){
  25
  26     // We start not desiring any temp
  27     this->desired_adc_value = UNDEFINED;
  28
  29     // Settings
  30     this->on_config_reload(this);
  31
  32     this->acceleration_factor = 10;
  33
  34     this->kernel->slow_ticker->attach( 20, this, &TemperatureControl::thermistor_read_tick );
  35
  36     // Register for events
  37     this->register_for_event(ON_GCODE_EXECUTE);
  38     this->register_for_event(ON_MAIN_LOOP);
  39
  40 }
  41
  42 void TemperatureControl::on_main_loop(void* argument){ }
  43
  44 // Get configuration from the config file
  45 void TemperatureControl::on_config_reload(void* argument){
  46
  47     // General config
  48     this->set_m_code          = this->kernel->config->value(temperature_control_checksum, this->name_checksum, set_m_code_checksum)->by_default(104)->as_number();
  49     this->set_and_wait_m_code = this->kernel->config->value(temperature_control_checksum, this->name_checksum, set_and_wait_m_code_checksum)->by_default(109)->as_number();
  50     this->get_m_code          = this->kernel->config->value(temperature_control_checksum, this->name_checksum, get_m_code_checksum)->by_default(105)->as_number();
  51     this->readings_per_second = this->kernel->config->value(temperature_control_checksum, this->name_checksum, readings_per_second_checksum)->by_default(5)->as_number();
  52
  53     // Values are here : http://reprap.org/wiki/Thermistor
  54     this->r0   = 100000;
  55     this->t0   = 25;
  56     this->beta = 4066;
  57     this->vadc = 3.3;
  58     this->vcc  = 3.3;
  59     this->r1   = 0;
  60     this->r2   = 4700;
  61
  62     // Preset values for various common types of thermistors
  63     ConfigValue* thermistor = this->kernel->config->value(temperature_control_checksum, this->name_checksum, thermistor_checksum);
  64     if(       thermistor->value.compare("EPCOS100K"    ) == 0 ){ // Default
  65     }else if( thermistor->value.compare("RRRF100K"     ) == 0 ){ this->beta = 3960;
  66     }else if( thermistor->value.compare("RRRF10K"      ) == 0 ){ this->beta = 3964; this->r0 = 10000; this->r1 = 680; this->r2 = 1600;
  67     }else if( thermistor->value.compare("Honeywell100K") == 0 ){ this->beta = 3974;
  68     }else if( thermistor->value.compare("Semitec"      ) == 0 ){ this->beta = 4267; }
  69
  70     // Preset values are overriden by specified values
  71     this->r0 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r0_checksum  )->by_default(100000)->as_number();               // Stated resistance eg. 100K
  72     this->t0 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, t0_checksum  )->by_default(25    )->as_number() + 273.15;      // Temperature at stated resistance, eg. 25C
  73     this->beta =                this->kernel->config->value(temperature_control_checksum, this->name_checksum, beta_checksum)->by_default(4066  )->as_number();               // Thermistor beta rating. See http://reprap.org/bin/view/Main/MeasuringThermistorBeta
  74     this->vadc =                this->kernel->config->value(temperature_control_checksum, this->name_checksum, vadc_checksum)->by_default(3.3   )->as_number();               // ADC Reference
  75     this->vcc  =                this->kernel->config->value(temperature_control_checksum, this->name_checksum, vcc_checksum )->by_default(3.3   )->as_number();               // Supply voltage to potential divider
  76     this->r1 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r1_checksum  )->by_default(0     )->as_number();
  77     this->r2 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r2_checksum  )->by_default(4700  )->as_number();
  78
  79     // Thermistor math
  80     this->k = this->r0 * exp( -this->beta / this->t0 );
  81     if( r1 > 0 ){ this->vs = r1 * this->vcc / ( r1 + r2 ); this->rs = r1 * r2 / ( r1 + r2 ); }else{ this->vs = this->vcc; this->rs = r2; }
  82
  83     // Thermistor pin for ADC readings
  84     this->thermistor_pin = this->kernel->config->value(temperature_control_checksum, this->name_checksum, thermistor_pin_checksum )->required()->as_pin();
  85     this->kernel->adc->enable_pin(this->thermistor_pin);
  86
  87     // Heater pin
  88     this->heater_pin     =  this->kernel->config->value(temperature_control_checksum, this->name_checksum, heater_pin_checksum)->required()->as_pin()->as_output();
  89     this->heater_pin->set(0);
  90
  91 }
  92
  93 //#pragma GCC push_options
  94 //#pragma GCC optimize ("O0")
  95
  96
  97 void TemperatureControl::on_gcode_execute(void* argument){
  98     Gcode* gcode = static_cast<Gcode*>(argument);
  99     if( gcode->has_m){
 100         // Set temperature without waiting
 101         if( gcode->m == this->set_m_code && gcode->has_letter('S') ){
 102             //gcode->stream->printf("setting to %f meaning %u  \r\n", gcode->get_value('S'), this->temperature_to_adc_value( gcode->get_value('S') ) );
 103             if (gcode->get_value('S') == 0)
 104             {
 105                 this->desired_adc_value = UNDEFINED;
 106                 this->heater_pin->set(0);
 107             }
 108             else
 109             {
 110             this->set_desired_temperature(gcode->get_value('S'));
 111         }
 112         }
 113         // Set temperature and wait
 114         if( gcode->m == this->set_and_wait_m_code && gcode->has_letter('S') ){
 115             if (gcode->get_value('S') == 0)
 116             {
 117                 this->desired_adc_value = UNDEFINED;
 118                 this->heater_pin->set(0);
 119             }
 120             else
 121             {
 122             this->set_desired_temperature(gcode->get_value('S'));
 123             // Pause
 124             this->kernel->pauser->take();
 125             this->waiting = true;
 126         }
 127         }
 128         // Get temperature
 129         if( gcode->m == this->get_m_code ){
 130             gcode->stream->printf("get temperature: %f current:%f target:%f bare_value:%u \r\n", this->get_temperature(), this->new_thermistor_reading(), this->desired_adc_value, this->kernel->adc->read(this->thermistor_pin)  );
 131         }
 132     }
 133 }
 134
 135 //#pragma GCC pop_options
 136
 137
 138 void TemperatureControl::set_desired_temperature(double desired_temperature){
 139     this->desired_adc_value = this->temperature_to_adc_value(desired_temperature);
 140 }
 141
 142 double TemperatureControl::get_temperature(){
 143     return this->adc_value_to_temperature( this->new_thermistor_reading() );
 144 }
 145
 146 double TemperatureControl::adc_value_to_temperature(double adc_value){
 147     double v = adc_value * this->vadc;            // Convert from 0-1 adc value to voltage
 148     double r = this->rs * v / ( this->vs - v );   // Resistance of thermistor
 149     return ( this->beta / log( r / this->k )) - 273.15;
 150 }
 151
 152 double TemperatureControl::temperature_to_adc_value(double temperature){
 153     double r = this->r0 * exp( this->beta * ( 1 / (temperature + 273.15) -1 / this->t0 ) ); // Resistance of the thermistor
 154     double v = this->vs * r / ( this->rs + r );                                             // Voltage at the potential divider
 155     return v / this->vadc * 1.00000;                                               // The ADC reading
 156 }
 157
 158 uint32_t TemperatureControl::thermistor_read_tick(uint32_t dummy){
 159     if( this->desired_adc_value != UNDEFINED ){
 160         double r = this->new_thermistor_reading();
 161         if ((r > 0.01) &&
 162             (r < 0.99) &&
 163             (r > this->desired_adc_value))
 164         {
 165             this->heater_pin->set(1);
 166         }
 167         else
 168         {
 169             if (((r <= 0.01) || (r >= 0.99)) && (this->desired_adc_value != UNDEFINED))
 170             {
 171                 this->kernel->streams->printf("MINTEMP triggered on P%d.%d! check your thermistors!\n", this->thermistor_pin->port_number, this->thermistor_pin->pin);
 172                 this->desired_adc_value = UNDEFINED;
 173             }
 174             this->heater_pin->set(0);
 175             if (this->waiting)
 176             {
 177                 this->kernel->pauser->release();
 178                 this->waiting = false;
 179             }
 180         }
 181     }
 182     return 0;
 183 }
 184
 185 double TemperatureControl::new_thermistor_reading(){
 186
 187     double new_reading = double( double(this->kernel->adc->read(this->thermistor_pin) / double(1<<12) ) );
 188
 189     if( this->queue.size() < 15 ){
 190         this->queue.push_back( new_reading );
 191         return new_reading;
 192     }else{
 193         double current_temp = this->average_adc_reading();
 194         double error = fabs(new_reading - current_temp);
 195         if( error < 0.1 ){
 196             this->error_count = 0;
 197             double test;
 198             this->queue.pop_front(test);
 199             this->queue.push_back( new_reading );
 200         }else{
 201             this->error_count++;
 202             if( this->error_count > 4 ){
 203                 double test;
 204                 this->queue.pop_front(test);
 205             }
 206         }
 207         return current_temp;
 208     }
 209 }
 210
 211
 212 double TemperatureControl::average_adc_reading(){
 213     double total = 0;
 214     int j = 0;
 215     int reading_index = this->queue.head;
 216     while( reading_index != this->queue.tail ){
 217         j++;
 218         total += this->queue.buffer[reading_index];
 219         reading_index = this->queue.next_block_index( reading_index );
 220     }
 221     return total / j;
 222 }
 223
 224
 225