Diff: modules/tools/temperaturecontrol/TemperatureControl.cpp

Revision:

0:31e91bb0ef3c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/modules/tools/temperaturecontrol/TemperatureControl.cpp	Tue Jul 31 21:11:18 2012 +0000
@@ -0,0 +1,187 @@
+/*  
+      This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
+      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.
+      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.
+      You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>. 
+*/
+
+// TODO : THIS FILE IS LAME, MUST BE MADE MUCH BETTER
+
+#include "libs/Module.h"
+#include "libs/Kernel.h"
+#include <math.h>
+#include "TemperatureControl.h"
+#include "libs/Pin.h"
+
+TemperatureControl::TemperatureControl(){}
+
+TemperatureControl::TemperatureControl(uint16_t name){
+    this->name_checksum = name;
+    this->error_count = 0; 
+}
+
+void TemperatureControl::on_module_loaded(){
+    
+    // We start not desiring any temp
+    this->desired_adc_value = UNDEFINED;
+
+    // Settings
+    this->on_config_reload(this);
+
+    this->acceleration_factor = 10;
+
+    this->kernel->slow_ticker->attach( 20, this, &TemperatureControl::thermistor_read_tick );
+
+    // Register for events
+    this->register_for_event(ON_GCODE_EXECUTE); 
+    this->register_for_event(ON_MAIN_LOOP); 
+
+}
+
+void TemperatureControl::on_main_loop(void* argument){ }
+
+// Get configuration from the config file
+void TemperatureControl::on_config_reload(void* argument){
+
+    this->readings_per_second = this->kernel->config->value(temperature_control_checksum, this->name_checksum, readings_per_second_checksum)->by_default(5)->as_number();
+
+    // Values are here : http://reprap.org/wiki/Thermistor
+    this->r0   = 100000;
+    this->t0   = 25;
+    this->beta = 4066;
+    this->vadc = 3.3;
+    this->vcc  = 3.3;
+    this->r1   = 0;
+    this->r2   = 4700;
+
+    // Preset values for various common types of thermistors
+    ConfigValue* thermistor = this->kernel->config->value(temperature_control_checksum, this->name_checksum, thermistor_checksum);    
+    if(       thermistor->value.compare("EPCOS100K"    ) == 0 ){ // Default
+    }else if( thermistor->value.compare("RRRF100K"     ) == 0 ){ this->beta = 3960;
+    }else if( thermistor->value.compare("RRRF10K"      ) == 0 ){ this->beta = 3964; this->r0 = 10000; this->r1 = 680; this->r2 = 1600;
+    }else if( thermistor->value.compare("Honeywell100K") == 0 ){ this->beta = 3974;
+    }else if( thermistor->value.compare("Semitec"      ) == 0 ){ this->beta = 4267; }
+
+    // Preset values are overriden by specified values
+    this->r0 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r0_checksum  )->by_default(100000)->as_number();               // Stated resistance eg. 100K
+    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
+    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
+    this->vadc =                this->kernel->config->value(temperature_control_checksum, this->name_checksum, vadc_checksum)->by_default(3.3   )->as_number();               // ADC Reference
+    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
+    this->r1 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r1_checksum  )->by_default(0     )->as_number();
+    this->r2 =                  this->kernel->config->value(temperature_control_checksum, this->name_checksum, r2_checksum  )->by_default(4700  )->as_number();
+    
+    // Thermistor math 
+    this->k = this->r0 * exp( -this->beta / this->t0 );
+    if( r1 > 0 ){ this->vs = r1 * this->vcc / ( r1 + r2 ); this->rs = r1 * r2 / ( r1 + r2 ); }else{ this->vs = this->vcc; this->rs = r2; } 
+
+    // Thermistor pin for ADC readings
+    this->thermistor_pin = this->kernel->config->value(temperature_control_checksum, this->name_checksum, thermistor_pin_checksum )->required()->as_pin();
+    this->kernel->adc->enable_pin(this->thermistor_pin);
+
+    // Heater pin
+    this->heater_pin     =  this->kernel->config->value(temperature_control_checksum, this->name_checksum, heater_pin_checksum)->required()->as_pin()->as_output();
+    this->heater_pin->set(0);
+
+}
+
+void TemperatureControl::on_gcode_execute(void* argument){
+    Gcode* gcode = static_cast<Gcode*>(argument);
+
+    // Set temperature without waiting
+    if( gcode->has_letter('M') && gcode->get_value('M') == 104 && gcode->has_letter('S') ){
+        this->set_desired_temperature(gcode->get_value('S')); 
+    } 
+
+    // Set temperature and wait
+    if( gcode->has_letter('M') && gcode->get_value('M') == 109 && gcode->has_letter('S') ){
+        this->set_desired_temperature(gcode->get_value('S'));
+        
+        // Pause 
+        this->kernel->pauser->take(); 
+        this->waiting = true; 
+    
+    } 
+
+    // Get temperature
+    if( gcode->has_letter('M') && gcode->get_value('M') == 105 ){
+        gcode->stream->printf("get temperature: %f current:%f target:%f \r\n", this->get_temperature(), this->new_thermistor_reading(), this->desired_adc_value );
+    } 
+}
+
+void TemperatureControl::set_desired_temperature(double desired_temperature){
+    this->desired_adc_value = this->temperature_to_adc_value(desired_temperature);
+}
+
+double TemperatureControl::get_temperature(){
+    double temp = this->new_thermistor_reading() ;
+    return this->adc_value_to_temperature( this->new_thermistor_reading() );
+}
+
+double TemperatureControl::adc_value_to_temperature(double adc_value){
+    double v = adc_value * this->vadc;            // Convert from 0-1 adc value to voltage
+    double r = this->rs * v / ( this->vs - v );   // Resistance of thermistor
+    return ( this->beta / log( r / this->k )) - 273.15;
+}
+
+double TemperatureControl::temperature_to_adc_value(double temperature){
+    double r = this->r0 * exp( this->beta * ( 1 / (temperature + 273.15) -1 / this->t0 ) ); // Resistance of the thermistor 
+    double v = this->vs * r / ( this->rs + r );                                             // Voltage at the potential divider
+    return v / this->vadc * 1.00000;                                               // The ADC reading
+}
+
+uint32_t TemperatureControl::thermistor_read_tick(uint32_t dummy){
+    if( this->desired_adc_value != UNDEFINED ){
+        if( this->new_thermistor_reading() > this->desired_adc_value ){
+            this->heater_pin->set(1); 
+        }else{
+            this->heater_pin->set(0); 
+            if( this->waiting ){ 
+                this->kernel->pauser->release();
+                this->waiting = false; 
+            }
+        }
+    }
+}
+
+double TemperatureControl::new_thermistor_reading(){
+   
+    double new_reading = double( double(this->kernel->adc->read(this->thermistor_pin) / double(1<<12) ) );
+
+    if( this->queue.size() < 15 ){
+        this->queue.push_back( new_reading );
+        return new_reading;
+    }else{
+        double current_temp = this->average_adc_reading();
+        double error = fabs(new_reading - current_temp); 
+        if( error < 0.1 ){
+            this->error_count = 0;
+            double test;
+            this->queue.pop_front(test); 
+            this->queue.push_back( new_reading );
+        }else{
+            this->error_count++;
+            if( this->error_count > 4 ){
+                double test;
+                this->queue.pop_front(test); 
+            }
+        } 
+        return current_temp;
+    }
+}
+
+
+double TemperatureControl::average_adc_reading(){
+    double total;
+    int j=0;
+    int reading_index = this->queue.head;
+    while( reading_index != this->queue.tail ){
+        j++;
+        total += this->queue.buffer[reading_index];
+        reading_index = this->queue.next_block_index( reading_index );
+    }
+    return total / j;
+}
+
+
+