add ds18b20 reading to firmware

README.md

@@ -1,6 +0,0 @@
-Raspberry Pi controlled Kiln
-============================
-
-This project implements a wifi-accessible temperature controller for a ceramic firing kiln.
-
-Please see the BOM for all the parts we purchased for this project. Additional circuit diagrams and 3D models will be forthcoming.

firmware/controller/controller.ino

@@ -3,7 +3,7 @@
 #define PIN_STEP2     8
 #define PIN_STEP3     7
 #define PIN_STEP4     6
-#define PIN_AUXTEMP   A1
+#define PIN_AUXTEMP   2
 #define PIN_TEMP_CS   4
 #define PIN_LOADCELL  A3
 #define PIN_FLAME_A   A2
@@ -12,8 +12,17 @@
 
 #define STEP_SPEED 275//in steps per second
 #define TEMP_UPDATE 250 //milliseconds
-#define MOTOR_TIMEOUT 5000 //milliseconds
+#define AUX_UPDATE 1000 //milliseconds
+#define MOTOR_TIMEOUT 60000 //milliseconds
 
+#define NUM_AUXTEMP 2
+
+#define NO_PORTB_PINCHANGES
+#define NO_PORTC_PINCHANGES
+#define DISABLE_PCINT_MULTI_SERVICE
+
+#include <OneWire.h>
+#include <DallasTemperature.h>
 #include <Stepper.h>
 #include <Wire.h>
 #include <SPI.h>
@@ -28,7 +37,7 @@ struct Status {
   float main_temp;
   float ambient;
   float weight;
-  float aux_temp[2];
+  float aux_temp[NUM_AUXTEMP];
 } status;
 uint8_t* status_data = (uint8_t*) &status;
 
@@ -36,22 +45,34 @@ const float step_interval = 1. / STEP_SPEED * 1000.; //milliseconds
 
 //intermediate variables
 Adafruit_MAX31855 thermo(PIN_TEMP_CS);
-Stepper stepper(2048, PIN_STEP1, PIN_STEP3, PIN_STEP2, PIN_STEP4);
+Stepper stepper(2048, PIN_STEP4, PIN_STEP2, PIN_STEP3, PIN_STEP1);
+pushbutton reglimit = pushbutton(PIN_REGLIMIT, 5);
+OneWire oneWire(PIN_AUXTEMP);
+DallasTemperature sensors(&oneWire);
+DeviceAddress aux_addr[NUM_AUXTEMP];
 
 char i2c_command;
 float next_step;
 unsigned long next_temp;
+unsigned long next_aux = 0;
 unsigned char motor_active = false;
 unsigned long stepper_target = 0;
-unsigned int n_clicks = 0; //Number of full rotations
+unsigned long num_aux = 0;
+int n_clicks = 0; //Number of full rotations
 boolean limit_state = false;
 unsigned long limit_last;
 
 void setup() {
+  //setup ignition mosfet
+  pinMode(PIN_IGNITE, OUTPUT);
+  digitalWrite(PIN_IGNITE, LOW);
+  status.ignite = 0.;
+  
   status.flame = false;
   status.weight = 0.;
-  status.aux_temp[0] = 0.;
+  status.aux_temp[0] = -1.;
-  status.aux_temp[1] = 0.;
+  status.aux_temp[1] = -1.;
+  sensors.begin();
   
   //Setup I2C
   Wire.begin(0x08);
@@ -61,33 +82,32 @@ void setup() {
   //Set up regulator stepper
   status.motor = 0;
   
-  //setup regulator limit switch
+  //set initial thermocouple temperature
-  pinMode(PIN_REGLIMIT, INPUT);
-  digitalWrite(PIN_REGLIMIT, HIGH);
-  
-  //setup ignition mosfet
-  pinMode(PIN_IGNITE, OUTPUT);
-  digitalWrite(PIN_IGNITE, LOW);
-  status.ignite = false;
-  
-  //set initial temperature
   delay(500);
   update_temp();
   next_temp = millis() + TEMP_UPDATE;
+  
+  //Setup auxtemp ds18b20 sensors
+  num_aux = sensors.getDeviceCount();
+  num_aux = NUM_AUXTEMP < num_aux ? NUM_AUXTEMP : num_aux;
+  for (int i = 0; i < num_aux; i++) {
+    sensors.getAddress(aux_addr[i], i);
+    sensors.setResolution(aux_addr[i], 12);
+    status.aux_temp[i] = 0.;
+  }
+  if (num_aux > 0) {
+    sensors.setWaitForConversion(false);
+    sensors.requestTemperatures();
+    next_aux = millis() + AUX_UPDATE;
+  }
 }
 
 int dir;
 unsigned long now;
 void loop() {
   now = millis();
-  if (digitalRead(PIN_REGLIMIT) == LOW) {
+  reglimit.update();
-    if (limit_last == 0) {
+  status.aux_temp[1] = reglimit.n_clicks;
-      limit_last = millis();
-    } else if ((millis() - limit_last) > 5) {
-      n_clicks += dir;
-      limit_last = 0;
-    }
-  }
   
   if (stepper_target != status.motor && now > next_step) {
     dir = status.motor < stepper_target ? 1 : -1;
@@ -95,7 +115,7 @@ void loop() {
     
     //Limit switch tripped
     if (stepper_target == 0) {
-      if (n_clicks == 0)
+      if (reglimit.n_clicks == 0)
         status.motor = 0;
     } else {
       status.motor += dir;
@@ -119,6 +139,12 @@ void loop() {
     next_temp += TEMP_UPDATE;
   }
   
+  //update auxtemp
+  if (num_aux > 0 && now > next_aux) {
+    update_aux();
+    next_aux += AUX_UPDATE;
+  }
+  
   //check flame status
 }
 
@@ -134,9 +160,14 @@ void update_temp() {
   thermo.readAll(status.main_temp, status.ambient);
 }
 
+void update_aux() {
+  for (int i = 0; i < num_aux; i++) {
+    status.aux_temp[i] = sensors.getTempC(aux_addr[i]);
+  }
+  sensors.requestTemperatures();
+}
+
 void i2c_update() {
-  //update temperatures
-  
   if (i2c_command == 'M') {
     Wire.write((byte*) &(status.motor), 4);
   } else if (i2c_command == 'I') {
@@ -170,7 +201,8 @@ void i2c_action(int nbytes) {
       set_regulator(*((unsigned int*) buffer));
       break;
     case 'I':
-      digitalWrite(PIN_IGNITE, buffer[0]);
+      analogWrite(PIN_IGNITE, buffer[0]);
+      status.ignite = buffer[0];
       break;
   }
   

firmware/controller/pushbutton.h

@@ -1,7 +1,7 @@
 class pushbutton : public CallBackInterface
 {
   public:
-    uint8_t n_clicks;
+    int n_clicks;
     uint8_t pin;
     unsigned int interval;
     unsigned long last;
@@ -11,8 +11,6 @@ class pushbutton : public CallBackInterface
       n_clicks = 0;
       last = 0;
       init();
-      state = digitalRead(pin);
-      
     };
     void cbmethod() {
       last = millis();
@@ -31,12 +29,11 @@ class pushbutton : public CallBackInterface
   
   private:
     int dir;
-    boolean state;
     
     void init () {
       pinMode(pin, INPUT);
       digitalWrite(pin, HIGH);
-      PCintPort::attachInterrupt(pin, this, FALLING);
+      PCintPort::attachInterrupt(pin, this, CHANGE);
     };
 };
 

firmware/controller_soft/controller_soft.ino

@@ -1,174 +0,0 @@
-#define PIN_IGNITE    10
-#define PIN_STEP1     9
-#define PIN_STEP2     8
-#define PIN_STEP3     7
-#define PIN_STEP4     6
-#define PIN_AUXTEMP   A1
-#define PIN_TEMP_CS   4
-#define PIN_LOADCELL  A3
-#define PIN_FLAME_A   A2
-#define PIN_FLAME_D   1
-#define PIN_REGLIMIT  5
-
-#define STEP_SPEED 275//in steps per second
-#define TEMP_UPDATE 250 //milliseconds
-#define MOTOR_TIMEOUT 5000 //milliseconds
-
-#define NO_PORTB_PINCHANGES
-#define NO_PORTC_PINCHANGES
-#define DISABLE_PCINT_MULTI_SERVICE
-
-#include <Stepper.h>
-#include <Wire.h>
-#include <SPI.h>
-#include <Adafruit_MAX31855.h>
-#include <ooPinChangeInt.h>
-#include "pushbutton.h"
-
-struct Status {
-  unsigned char ignite;
-  unsigned char flame;
-  unsigned int motor;
-  float main_temp;
-  float ambient;
-  float weight;
-  float aux_temp[2];
-} status;
-uint8_t* status_data = (uint8_t*) &status;
-
-const float step_interval = 1. / STEP_SPEED * 1000.; //milliseconds
-
-//intermediate variables
-Adafruit_MAX31855 thermo(PIN_TEMP_CS);
-Stepper stepper(2048, PIN_STEP4, PIN_STEP2, PIN_STEP3, PIN_STEP1);
-pushbutton reglimit = pushbutton(PIN_REGLIMIT, 5);
-
-char i2c_command;
-float next_step;
-unsigned long next_temp;
-unsigned char motor_active = false;
-unsigned long stepper_target = 0;
-int n_clicks = 0; //Number of full rotations
-boolean limit_state = false;
-unsigned long limit_last;
-
-void setup() {
-  status.flame = false;
-  status.weight = 0.;
-  status.aux_temp[0] = 0.;
-  status.aux_temp[1] = 0.;
-  
-  //Setup I2C
-  Wire.begin(0x08);
-  Wire.onRequest(i2c_update);
-  Wire.onReceive(i2c_action);
-  
-  //Set up regulator stepper
-  status.motor = 0;
-  
-  //setup ignition mosfet
-  pinMode(PIN_IGNITE, OUTPUT);
-  digitalWrite(PIN_IGNITE, LOW);
-  status.ignite = false;
-  
-  //set initial temperature
-  delay(500);
-  update_temp();
-  next_temp = millis() + TEMP_UPDATE;
-}
-
-int dir;
-unsigned long now;
-void loop() {
-  now = millis();
-  reglimit.update();
-  status.aux_temp[0] = reglimit.n_clicks;
-  
-  if (stepper_target != status.motor && now > next_step) {
-    dir = status.motor < stepper_target ? 1 : -1;
-    stepper.step(dir);
-    
-    //Limit switch tripped
-    if (stepper_target == 0) {
-      if (reglimit.n_clicks == 0)
-        status.motor = 0;
-    } else {
-      status.motor += dir;
-    }
-    
-    next_step += step_interval;
-  }
-  
-  //put motor to sleep after timeout
-  if (motor_active && (now - next_step) > MOTOR_TIMEOUT) {
-    digitalWrite(PIN_STEP1, LOW);
-    digitalWrite(PIN_STEP2, LOW);
-    digitalWrite(PIN_STEP3, LOW);
-    digitalWrite(PIN_STEP4, LOW);
-    motor_active = false;
-  }
-  
-  //update temperature
-  if (now > next_temp) {
-    update_temp();
-    next_temp += TEMP_UPDATE;
-  }
-  
-  //check flame status
-}
-
-void set_regulator(unsigned long pos) {
-  motor_active = true;
-  reglimit.setDir(status.motor < pos ? 1 : -1);
-  if (stepper_target == status.motor)
-    next_step = millis(); //Start stepping immediately
-  stepper_target = pos;
-}
-
-void update_temp() {
-  thermo.readAll(status.main_temp, status.ambient);
-}
-
-void i2c_update() {
-  //update temperatures
-  
-  if (i2c_command == 'M') {
-    Wire.write((byte*) &(status.motor), 4);
-  } else if (i2c_command == 'I') {
-    Wire.write((byte*) &(status.ignite), 1);
-  } else if (i2c_command == 'T') {
-    Wire.write((byte*) &(status.main_temp), 4);
-  } else if (i2c_command == 'F') {
-    Wire.write((byte*) &(status.flame), 1);
-  } else {
-    Wire.write(status_data, sizeof(struct Status));
-  }
-  
-  i2c_command = 0;
-}
-
-byte buffer[32];
-void i2c_action(int nbytes) {
-  i2c_command = Wire.read();
-  
-  int i = 0;
-  while (Wire.available()) {
-    buffer[i++] = Wire.read();
-  }
-  
-  if (nbytes == 1) {
-    return; //Command already stored, no arguments
-  }
-  
-  switch (i2c_command) {
-    case 'M':
-      set_regulator(*((unsigned int*) buffer));
-      break;
-    case 'I':
-      analogWrite(PIN_IGNITE, buffer[0]);
-      status.ignite = buffer[0];
-      break;
-  }
-  
-  i2c_command = 0;
-}

firmware/controller_soft/protocol.cpp

@@ -1,39 +0,0 @@
-#include "protocol.h"
-
-char Comm::buffer[BUFFER_LENGTH+1];
-int Comm::_nacts;
-char Comm::_commands[MAX_ACTIONS];
-char* (*Comm::_actions[MAX_ACTIONS])(int, char*);
-char Comm::_current_cmd;
-int  Comm::_current_len;
-
-Comm::Comm(int addr) {
-  Wire.begin(addr);
-  Wire.onReceive(_handle_request);
-  Wire.onRequest(_handle_response);
-}
-
-int Comm::action(char cmd, char* (*func)(int, char*)) {
-  if (_nacts >= MAX_ACTIONS)
-    return 1;
-    
-  _actions[_nacts] = func;
-  return 0;
-}
-
-void Comm::_handle_request(int nbytes) {
-  _current_cmd = Wire.read();
-  _current_len = nbytes-1;
-  for (int i = 0; i < nbytes-1; i++) {
-    buffer[i] = Wire.read();
-  }
-}
-
-void Comm::_handle_response() {
-  for (int i = 0; i < MAX_ACTIONS; i++) {
-    if (_commands[i] == _current_cmd) {
-      _actions[i](_current_len, buffer);
-    }
-  }
-  Wire.write(buffer);
-}

firmware/controller_soft/protocol.h

@@ -1,25 +0,0 @@
-#ifndef PROTOCOL_H
-#define PROTOCOL_H
-
-#include "Wire.h"
-
-#define MAX_ACTIONS 16
-
-class Comm {
-  private:
-    static char buffer[BUFFER_LENGTH+1];
-    static int _nacts;
-    static char _commands[MAX_ACTIONS];
-    static char* (*_actions[MAX_ACTIONS])(int, char*);
-    static char _current_cmd;
-    static int  _current_len;
-    
-    static void _handle_request(int);
-    static void _handle_response(void);
-  
-  public:
-    Comm(int addr);
-    int action(char, char* (*)(int, char*));
-};
-
-#endif //PROTOCOL_H

firmware/controller_soft/pushbutton.h

@@ -1,39 +0,0 @@
-class pushbutton : public CallBackInterface
-{
-  public:
-    int n_clicks;
-    uint8_t pin;
-    unsigned int interval;
-    unsigned long last;
-    
-    pushbutton (uint8_t _pin, unsigned int _interval): pin(_pin) , interval(_interval) {
-      dir = 0;
-      n_clicks = 0;
-      last = 0;
-      init();
-    };
-    void cbmethod() {
-      last = millis();
-    };
-    
-    void update() {
-      if (last != 0 && (millis() - last) > interval) {
-        n_clicks += dir;
-        last = 0;
-      }
-    }
-    
-    void setDir(int d) {
-      dir = d;
-    }
-  
-  private:
-    int dir;
-    
-    void init () {
-      pinMode(pin, INPUT);
-      digitalWrite(pin, HIGH);
-      PCintPort::attachInterrupt(pin, this, CHANGE);
-    };
-};
-