Jens Temperature Sensor Coaster

This coaster detects the temperature of a cup. You get a signal when it is ready to drink.

Dec 11, 2017

•

12594 views

•

15 respects

food and drinks

Devices & Components

Arduino Nano

Resistor 680 ohm 0.4w

Green LED 565nm 2.2v 2...5mA

Resistor 68 ohm 0.4w

Rubber feets sticker 10 mm diameter 2 mm high

Shrink Tube

Resistor 560 ohm 0.4w

Temperature Sensor

Blue LED 455nm 3.8v 20mA

Red LED 625nm 1.8v 2..5mA

Hardware & Tools

3D Printer, ABS Filament

Soldering iron (generic)

Sidecutter

Software & Tools

Visual Studio 2015

Fusion 360

Project description

Code

The sketch for the coaster

arduino

This program is loded into the coaster it is reading the temperature sensor and lighting the LEDs based on the given ranges.

1#include <EEPROM.h>
2
3#define AREF 3.3         // we tie 3.3V to   ARef and measure it with a multimeter!
4
5//Vout TMP36 > A1
6//3.3V > V+ TMP36   > AREF
7//GND TMP36 > GND
8//D6 > Piezo > GND
9//D7 > Blue Led (+), Blue Led   (-) > 60 Ohm > GND
10//D8 > Green Led (+), Green Led (-) > 560 Ohm > GND
11//D9   > Red Led (+), Red Led (-) > 640 Ohm > GND
12
13int iPinTemperature = 1;
14int   iTemperatureReading;
15int iPinLedRed = 9;
16int iPinLedGreen = 8;
17int iPinLedBlue   = 7;
18int iPinBuzzer = 6;
19String strSerialInput = "";
20bool bSerialInputComplete   = false;
21float fTopTemperature = 100;
22float fBottomTemperature = 0;
23int   iEEPROMTopTemperature = 0;
24int iEEPROMBottomTemperature = 4;
25int iEEPROMDisplayCelcius   = 8;
26int iEEPROMPlayTopTemperatureSound = 9;
27int iEEPROMPlayBottomTemperatureSound   = 10;
28bool bPlayTopTemperatureSound = false;
29bool bPlayBottomTemperatureSound   = false;
30bool bTempDisplaysCelcius = true;
31float fPreviousTemperature = 0;
32//   Number of average temperatures in celcius
33#define AVGC 13
34#define POSCOUNT   10
35float fArrTemps[AVGC]; // Array used to calculate the average temperature
36float   fArrTempsD[AVGC]; // Array used to calculate the average delta temperature
37int   iLEDConfigCurrent = 0; // 1 = Red, 0 = Green, -1 = Blue
38int iLEDConfigPrevious   = 0; // 1 = Red, 0 = Green, -1 = Blue
39bool bLEDsActive = false;
40bool bLEDsBlink   = false;
41float fAverageTemp;
42float fAverageTempD;
43int iDeltaPositiveCount;
44bool   bInitAverage = true;
45int iAvgIndex;
46long lMilliSecondsSinceBeep = -1;
47long   iMilliSecondsSinceBeepCount = 50000;
48long iMilliSecondsSinceLastSwitchCount =   900000;
49long lMilliSecondsSinceLastSwitch = iMilliSecondsSinceLastSwitchCount;
50    
51void setup(void)
52{
53  // We'll send debugging information via the Serial   monitor
54  Serial.begin(9600);
55  Serial.println("Setup");  
56 
57  //   If you want to set the aref to something other than 5v
58  analogReference(EXTERNAL);
59   pinMode(iPinLedRed, OUTPUT);
60  pinMode(iPinLedGreen, OUTPUT);
61  pinMode(iPinLedBlue,   OUTPUT);
62
63  strSerialInput.reserve(20);
64
65  long lTop = EEPROMReadlong(iEEPROMTopTemperature);
66   if (lTop < 0 || lTop > 10000)
67  {
68    lTop = 4500;
69  }
70  long lBottom   = EEPROMReadlong(iEEPROMBottomTemperature);
71  if (lBottom < 0 || lBottom > 10000)
72   {
73    lBottom = 3900;
74  }
75
76  if (lTop < lBottom)
77  {
78    lTop   = 4500;
79    lBottom = 3900;
80  }
81  fTopTemperature = (float)lTop / (float)100;
82   fBottomTemperature = (float)lBottom / (float)100;
83  bTempDisplaysCelcius =   EEPROM.read(iEEPROMDisplayCelcius) == 1;
84  
85  bPlayTopTemperatureSound = EEPROM.read(iEEPROMPlayTopTemperatureSound)   == 1;
86  bPlayBottomTemperatureSound = EEPROM.read(iEEPROMPlayBottomTemperatureSound)   == 1;
87}
88 
89 
90void loop(void)
91{
92  if (bSerialInputComplete)
93   {
94    Serial.println(strSerialInput);
95    strSerialInput = "";
96    bSerialInputComplete   = false;
97  }
98  
99  iTemperatureReading = analogRead(iPinTemperature);  
100   // Converting temperature voltage to temperature using AREF
101  float fTemperatureVoltage   = iTemperatureReading * AREF;
102  fTemperatureVoltage /= 1024.0;
103  float fTemperatureC   = (fTemperatureVoltage - 0.5) * 100 ;  //converting from 10 mv per degree with 500   mV offset to degrees ((fTemperatureVoltage - 500mV) times 100
104
105  // Initialize   average arrays etc
106  if (bInitAverage)
107  {
108    for (int j = 0; j < AVGC;   j++)
109    {
110      fArrTemps[j] = fTemperatureC;
111      fArrTempsD[j] = (float)-0.01;
112     }
113    bInitAverage = false;
114    iAvgIndex = 0;
115    fAverageTemp = fTemperatureC;
116     fPreviousTemperature = fTemperatureC;
117    bLEDsActive = true;
118    lMilliSecondsSinceBeep   = millis();
119    iLEDConfigPrevious = -1;
120  }
121
122  // Point to next average   in the arrays
123  iAvgIndex++;
124  if (iAvgIndex > AVGC - 1)
125  {
126    iAvgIndex   = 0;
127  }
128
129  fArrTemps[iAvgIndex] = fTemperatureC;
130
131  // Calculate   averages
132  fAverageTemp = 0;
133  int iPosCount = 0;
134  for (int j = 0; j <   AVGC; j++)
135  {
136    if (fArrTempsD[j] > (float)0.0)
137    {
138      iPosCount++;
139     }
140    fAverageTemp += fArrTemps[j];
141    fAverageTempD += fArrTempsD[j];
142   }
143
144  fAverageTemp = fAverageTemp / (float)AVGC;
145  fAverageTempD = fAverageTempD   / (float)AVGC;
146 
147  Serial.print("[it:"); Serial.print(fTemperatureC);Serial.print(",tt:");
148   Serial.print(fTopTemperature);Serial.print(",bt:");
149  Serial.print(fBottomTemperature);Serial.print(",dc:");
150   Serial.print(bTempDisplaysCelcius);
151  Serial.print(",at:");Serial.print(fAverageTemp);
152   Serial.print(",pt:");Serial.print(bPlayTopTemperatureSound);
153  Serial.print(",pb:");Serial.print(bPlayBottomTemperatureSound);
154   Serial.println("]");
155
156  if (fAverageTemp >= fTopTemperature)
157  {
158     iLEDConfigCurrent = 1; // Red
159  }
160  if (fAverageTemp <= fBottomTemperature)
161   {
162    iLEDConfigCurrent = -1; // Blue
163  }
164  if (fAverageTemp > fBottomTemperature   && fAverageTemp < fTopTemperature)
165  {
166    iLEDConfigCurrent = 0; // Green
167   }
168
169  if (iLEDConfigCurrent >= 0 || (iLEDConfigCurrent == -1 && fAverageTempD   > 0 && iPosCount >= POSCOUNT))
170  {
171    lMilliSecondsSinceLastSwitch = millis();
172   }
173  
174  bLEDsActive = ((millis() - lMilliSecondsSinceLastSwitch) < iMilliSecondsSinceLastSwitchCount);
175
176   if (iLEDConfigPrevious == 1 && iLEDConfigCurrent == 0)
177  {
178      PlayUp();
179   }
180
181  if (iLEDConfigPrevious == 0 && iLEDConfigCurrent == -1)
182  {
183       PlayDown();
184  }
185
186  if (!bLEDsActive || (fAverageTempD > 0 && iPosCount   >= POSCOUNT && !bLEDsBlink))
187  {
188    digitalWrite(iPinLedRed, LOW);
189    digitalWrite(iPinLedGreen,   LOW);
190    digitalWrite(iPinLedBlue, LOW);
191  }
192  else
193  {
194    if (iLEDConfigCurrent   == 1)
195    {
196      digitalWrite(iPinLedRed, HIGH);
197      digitalWrite(iPinLedGreen,   LOW);
198      digitalWrite(iPinLedBlue, LOW);
199    }
200    if (iLEDConfigCurrent   == 0)
201    {
202      digitalWrite(iPinLedRed, LOW);
203      digitalWrite(iPinLedGreen,   HIGH);
204      digitalWrite(iPinLedBlue, LOW);
205    }
206    if (iLEDConfigCurrent   == -1)
207    {
208      digitalWrite(iPinLedRed, LOW);
209      digitalWrite(iPinLedGreen,   LOW);
210      digitalWrite(iPinLedBlue, HIGH);
211    }
212  }
213
214  fArrTempsD[iAvgIndex]   = fAverageTemp - fPreviousTemperature;
215  fPreviousTemperature = fAverageTemp;
216   iLEDConfigPrevious = iLEDConfigCurrent;
217  bLEDsBlink = !bLEDsBlink;
218  delay(450);
219}
220
221void   serialEvent()
222{
223  while (Serial.available())
224  {
225    // get the new   byte:
226    char inChar = (char)Serial.read();
227    // add it to the strSerialInput:
228     strSerialInput += inChar;
229    // if the incoming character is a newline,   set a flag so the main loop can
230    // do something about it:
231    if (inChar   == '\
232')
233    {
234      bSerialInputComplete = true;
235
236      if (strSerialInput.startsWith("tt:"))
237       {
238          strSerialInput = strSerialInput.substring(3);
239          fTopTemperature   = strSerialInput.toFloat();
240          EEPROMWritelong(iEEPROMTopTemperature,   (long)(fTopTemperature * (float)100));
241      }
242
243      if (strSerialInput.startsWith("bt:"))
244       {
245          strSerialInput = strSerialInput.substring(3);
246          fBottomTemperature   = strSerialInput.toFloat();
247          EEPROMWritelong(iEEPROMBottomTemperature,   (long)(fBottomTemperature * (float)100));
248      }
249
250      bTempDisplaysCelcius   = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("dc:", bTempDisplaysCelcius,   iEEPROMDisplayCelcius);
251      bPlayTopTemperatureSound = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pt:",   bPlayTopTemperatureSound, iEEPROMPlayTopTemperatureSound);
252      bPlayBottomTemperatureSound   = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pb:", bPlayBottomTemperatureSound,   iEEPROMPlayBottomTemperatureSound);
253    }
254  }
255}
256
257bool ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool(String   ip_strCommand, bool ip_bOriginalValue, int ip_iEEPROM_Location)
258{
259  bool _bResult   = ip_bOriginalValue;
260  if (strSerialInput.startsWith(ip_strCommand))
261  {
262     strSerialInput = strSerialInput.substring(3);
263    _bResult = (strSerialInput   == "1\
264");
265    EEPROM.write(ip_iEEPROM_Location, _bResult);
266  }
267  return   _bResult;
268}
269
270void EEPROMWritelong(int address, long value)
271{
272  byte   by;
273  for(int i=0;i< 4;i++) {
274    by = (value >> ((3-i)*8)) & 0x000000ff;   
275    EEPROM.write(address+i, by);
276  }
277}
278
279
280long EEPROMReadlong(long   address)
281{
282  long lo=0;
283
284  for(int i=0;i< 3;i++){
285    lo += EEPROM.read(address+i);
286     lo = lo << 8;
287  }
288  lo += EEPROM.read(address+3);
289  return lo;
290}
291
292void   PlayUp()
293{
294  if (bPlayTopTemperatureSound && (millis() - lMilliSecondsSinceBeep   > iMilliSecondsSinceBeepCount))
295  { 
296    tone(iPinBuzzer, 440, 100);
297    delay(100);
298     tone(iPinBuzzer, 880, 100);
299    delay(100);
300    tone(iPinBuzzer, 1760,   100);
301    lMilliSecondsSinceBeep = millis();
302  }
303}
304
305void PlayDown()
306{
307   if (bPlayBottomTemperatureSound && (millis() - lMilliSecondsSinceBeep > iMilliSecondsSinceBeepCount))
308   { 
309    tone(iPinBuzzer, 1760, 100);
310    delay(100);
311    tone(iPinBuzzer,   880, 100);
312    delay(100);
313    tone(iPinBuzzer, 440, 100);
314    lMilliSecondsSinceBeep   = millis();
315  }
316}
317
318

#include <EEPROM.h>

#define AREF 3.3         // we tie 3.3V to   ARef and measure it with a multimeter!

//Vout TMP36 > A1
//3.3V > V+ TMP36   > AREF
//GND TMP36 > GND
//D6 > Piezo > GND
//D7 > Blue Led (+), Blue Led   (-) > 60 Ohm > GND
//D8 > Green Led (+), Green Led (-) > 560 Ohm > GND
//D9   > Red Led (+), Red Led (-) > 640 Ohm > GND

int iPinTemperature = 1;
int   iTemperatureReading;
int iPinLedRed = 9;
int iPinLedGreen = 8;
int iPinLedBlue   = 7;
int iPinBuzzer = 6;
String strSerialInput = "";
bool bSerialInputComplete   = false;
float fTopTemperature = 100;
float fBottomTemperature = 0;
int   iEEPROMTopTemperature = 0;
int iEEPROMBottomTemperature = 4;
int iEEPROMDisplayCelcius   = 8;
int iEEPROMPlayTopTemperatureSound = 9;
int iEEPROMPlayBottomTemperatureSound   = 10;
bool bPlayTopTemperatureSound = false;
bool bPlayBottomTemperatureSound   = false;
bool bTempDisplaysCelcius = true;
float fPreviousTemperature = 0;
//   Number of average temperatures in celcius
#define AVGC 13
#define POSCOUNT   10
float fArrTemps[AVGC]; // Array used to calculate the average temperature
float   fArrTempsD[AVGC]; // Array used to calculate the average delta temperature
int   iLEDConfigCurrent = 0; // 1 = Red, 0 = Green, -1 = Blue
int iLEDConfigPrevious   = 0; // 1 = Red, 0 = Green, -1 = Blue
bool bLEDsActive = false;
bool bLEDsBlink   = false;
float fAverageTemp;
float fAverageTempD;
int iDeltaPositiveCount;
bool   bInitAverage = true;
int iAvgIndex;
long lMilliSecondsSinceBeep = -1;
long   iMilliSecondsSinceBeepCount = 50000;
long iMilliSecondsSinceLastSwitchCount =   900000;
long lMilliSecondsSinceLastSwitch = iMilliSecondsSinceLastSwitchCount;
    
void setup(void)
{
  // We'll send debugging information via the Serial   monitor
  Serial.begin(9600);
  Serial.println("Setup");  
 
  //   If you want to set the aref to something other than 5v
  analogReference(EXTERNAL);
   pinMode(iPinLedRed, OUTPUT);
  pinMode(iPinLedGreen, OUTPUT);
  pinMode(iPinLedBlue,   OUTPUT);

  strSerialInput.reserve(20);

  long lTop = EEPROMReadlong(iEEPROMTopTemperature);
   if (lTop < 0 || lTop > 10000)
  {
    lTop = 4500;
  }
  long lBottom   = EEPROMReadlong(iEEPROMBottomTemperature);
  if (lBottom < 0 || lBottom > 10000)
   {
    lBottom = 3900;
  }

  if (lTop < lBottom)
  {
    lTop   = 4500;
    lBottom = 3900;
  }
  fTopTemperature = (float)lTop / (float)100;
   fBottomTemperature = (float)lBottom / (float)100;
  bTempDisplaysCelcius =   EEPROM.read(iEEPROMDisplayCelcius) == 1;
  
  bPlayTopTemperatureSound = EEPROM.read(iEEPROMPlayTopTemperatureSound)   == 1;
  bPlayBottomTemperatureSound = EEPROM.read(iEEPROMPlayBottomTemperatureSound)   == 1;
}
 
 
void loop(void)
{
  if (bSerialInputComplete)
   {
    Serial.println(strSerialInput);
    strSerialInput = "";
    bSerialInputComplete   = false;
  }
  
  iTemperatureReading = analogRead(iPinTemperature);  
   // Converting temperature voltage to temperature using AREF
  float fTemperatureVoltage   = iTemperatureReading * AREF;
  fTemperatureVoltage /= 1024.0;
  float fTemperatureC   = (fTemperatureVoltage - 0.5) * 100 ;  //converting from 10 mv per degree with 500   mV offset to degrees ((fTemperatureVoltage - 500mV) times 100

  // Initialize   average arrays etc
  if (bInitAverage)
  {
    for (int j = 0; j < AVGC;   j++)
    {
      fArrTemps[j] = fTemperatureC;
      fArrTempsD[j] = (float)-0.01;
     }
    bInitAverage = false;
    iAvgIndex = 0;
    fAverageTemp = fTemperatureC;
     fPreviousTemperature = fTemperatureC;
    bLEDsActive = true;
    lMilliSecondsSinceBeep   = millis();
    iLEDConfigPrevious = -1;
  }

  // Point to next average   in the arrays
  iAvgIndex++;
  if (iAvgIndex > AVGC - 1)
  {
    iAvgIndex   = 0;
  }

  fArrTemps[iAvgIndex] = fTemperatureC;

  // Calculate   averages
  fAverageTemp = 0;
  int iPosCount = 0;
  for (int j = 0; j <   AVGC; j++)
  {
    if (fArrTempsD[j] > (float)0.0)
    {
      iPosCount++;
     }
    fAverageTemp += fArrTemps[j];
    fAverageTempD += fArrTempsD[j];
   }

  fAverageTemp = fAverageTemp / (float)AVGC;
  fAverageTempD = fAverageTempD   / (float)AVGC;
 
  Serial.print("[it:"); Serial.print(fTemperatureC);Serial.print(",tt:");
   Serial.print(fTopTemperature);Serial.print(",bt:");
  Serial.print(fBottomTemperature);Serial.print(",dc:");
   Serial.print(bTempDisplaysCelcius);
  Serial.print(",at:");Serial.print(fAverageTemp);
   Serial.print(",pt:");Serial.print(bPlayTopTemperatureSound);
  Serial.print(",pb:");Serial.print(bPlayBottomTemperatureSound);
   Serial.println("]");

  if (fAverageTemp >= fTopTemperature)
  {
     iLEDConfigCurrent = 1; // Red
  }
  if (fAverageTemp <= fBottomTemperature)
   {
    iLEDConfigCurrent = -1; // Blue
  }
  if (fAverageTemp > fBottomTemperature   && fAverageTemp < fTopTemperature)
  {
    iLEDConfigCurrent = 0; // Green
   }

  if (iLEDConfigCurrent >= 0 || (iLEDConfigCurrent == -1 && fAverageTempD   > 0 && iPosCount >= POSCOUNT))
  {
    lMilliSecondsSinceLastSwitch = millis();
   }
  
  bLEDsActive = ((millis() - lMilliSecondsSinceLastSwitch) < iMilliSecondsSinceLastSwitchCount);

   if (iLEDConfigPrevious == 1 && iLEDConfigCurrent == 0)
  {
      PlayUp();
   }

  if (iLEDConfigPrevious == 0 && iLEDConfigCurrent == -1)
  {
       PlayDown();
  }

  if (!bLEDsActive || (fAverageTempD > 0 && iPosCount   >= POSCOUNT && !bLEDsBlink))
  {
    digitalWrite(iPinLedRed, LOW);
    digitalWrite(iPinLedGreen,   LOW);
    digitalWrite(iPinLedBlue, LOW);
  }
  else
  {
    if (iLEDConfigCurrent   == 1)
    {
      digitalWrite(iPinLedRed, HIGH);
      digitalWrite(iPinLedGreen,   LOW);
      digitalWrite(iPinLedBlue, LOW);
    }
    if (iLEDConfigCurrent   == 0)
    {
      digitalWrite(iPinLedRed, LOW);
      digitalWrite(iPinLedGreen,   HIGH);
      digitalWrite(iPinLedBlue, LOW);
    }
    if (iLEDConfigCurrent   == -1)
    {
      digitalWrite(iPinLedRed, LOW);
      digitalWrite(iPinLedGreen,   LOW);
      digitalWrite(iPinLedBlue, HIGH);
    }
  }

  fArrTempsD[iAvgIndex]   = fAverageTemp - fPreviousTemperature;
  fPreviousTemperature = fAverageTemp;
   iLEDConfigPrevious = iLEDConfigCurrent;
  bLEDsBlink = !bLEDsBlink;
  delay(450);
}

void   serialEvent()
{
  while (Serial.available())
  {
    // get the new   byte:
    char inChar = (char)Serial.read();
    // add it to the strSerialInput:
     strSerialInput += inChar;
    // if the incoming character is a newline,   set a flag so the main loop can
    // do something about it:
    if (inChar   == '\
')
    {
      bSerialInputComplete = true;

      if (strSerialInput.startsWith("tt:"))
       {
          strSerialInput = strSerialInput.substring(3);
          fTopTemperature   = strSerialInput.toFloat();
          EEPROMWritelong(iEEPROMTopTemperature,   (long)(fTopTemperature * (float)100));
      }

      if (strSerialInput.startsWith("bt:"))
       {
          strSerialInput = strSerialInput.substring(3);
          fBottomTemperature   = strSerialInput.toFloat();
          EEPROMWritelong(iEEPROMBottomTemperature,   (long)(fBottomTemperature * (float)100));
      }

      bTempDisplaysCelcius   = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("dc:", bTempDisplaysCelcius,   iEEPROMDisplayCelcius);
      bPlayTopTemperatureSound = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pt:",   bPlayTopTemperatureSound, iEEPROMPlayTopTemperatureSound);
      bPlayBottomTemperatureSound   = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pb:", bPlayBottomTemperatureSound,   iEEPROMPlayBottomTemperatureSound);
    }
  }
}

bool ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool(String   ip_strCommand, bool ip_bOriginalValue, int ip_iEEPROM_Location)
{
  bool _bResult   = ip_bOriginalValue;
  if (strSerialInput.startsWith(ip_strCommand))
  {
     strSerialInput = strSerialInput.substring(3);
    _bResult = (strSerialInput   == "1\
");
    EEPROM.write(ip_iEEPROM_Location, _bResult);
  }
  return   _bResult;
}

void EEPROMWritelong(int address, long value)
{
  byte   by;
  for(int i=0;i< 4;i++) {
    by = (value >> ((3-i)*8)) & 0x000000ff;   
    EEPROM.write(address+i, by);
  }
}


long EEPROMReadlong(long   address)
{
  long lo=0;

  for(int i=0;i< 3;i++){
    lo += EEPROM.read(address+i);
     lo = lo << 8;
  }
  lo += EEPROM.read(address+3);
  return lo;
}

void   PlayUp()
{
  if (bPlayTopTemperatureSound && (millis() - lMilliSecondsSinceBeep   > iMilliSecondsSinceBeepCount))
  { 
    tone(iPinBuzzer, 440, 100);
    delay(100);
     tone(iPinBuzzer, 880, 100);
    delay(100);
    tone(iPinBuzzer, 1760,   100);
    lMilliSecondsSinceBeep = millis();
  }
}

void PlayDown()
{
   if (bPlayBottomTemperatureSound && (millis() - lMilliSecondsSinceBeep > iMilliSecondsSinceBeepCount))
   { 
    tone(iPinBuzzer, 1760, 100);
    delay(100);
    tone(iPinBuzzer,   880, 100);
    delay(100);
    tone(iPinBuzzer, 440, 100);
    lMilliSecondsSinceBeep   = millis();
  }
}

The configuration program made with c# and Visual Studio 2017 community edition

csharp

This program displays the settings of the coaster and makes it possible to change the settings. Here is an archive with the solution and the icons, c# etc

1inary file (no preview

inary file (no preview

The configuration program made with c# and Visual Studio 2017 community edition

csharp

This program displays the settings of the coaster and makes it possible to change the settings. Here is an archive with the solution and the icons, c# etc

1inary file (no preview

inary file (no preview

The sketch for the coaster

arduino

This program is loded into the coaster it is reading the temperature sensor and lighting the LEDs based on the given ranges.

1#include <EEPROM.h>
2
3#define AREF 3.3         // we tie 3.3V to  ARef and measure it with a multimeter!
4
5//Vout TMP36 > A1
6//3.3V > V+ TMP36  > AREF
7//GND TMP36 > GND
8//D6 > Piezo > GND
9//D7 > Blue Led (+), Blue Led  (-) > 60 Ohm > GND
10//D8 > Green Led (+), Green Led (-) > 560 Ohm > GND
11//D9  > Red Led (+), Red Led (-) > 640 Ohm > GND
12
13int iPinTemperature = 1;
14int  iTemperatureReading;
15int iPinLedRed = 9;
16int iPinLedGreen = 8;
17int iPinLedBlue  = 7;
18int iPinBuzzer = 6;
19String strSerialInput = "";
20bool bSerialInputComplete  = false;
21float fTopTemperature = 100;
22float fBottomTemperature = 0;
23int  iEEPROMTopTemperature = 0;
24int iEEPROMBottomTemperature = 4;
25int iEEPROMDisplayCelcius  = 8;
26int iEEPROMPlayTopTemperatureSound = 9;
27int iEEPROMPlayBottomTemperatureSound  = 10;
28bool bPlayTopTemperatureSound = false;
29bool bPlayBottomTemperatureSound  = false;
30bool bTempDisplaysCelcius = true;
31float fPreviousTemperature = 0;
32//  Number of average temperatures in celcius
33#define AVGC 13
34#define POSCOUNT  10
35float fArrTemps[AVGC]; // Array used to calculate the average temperature
36float  fArrTempsD[AVGC]; // Array used to calculate the average delta temperature
37int  iLEDConfigCurrent = 0; // 1 = Red, 0 = Green, -1 = Blue
38int iLEDConfigPrevious  = 0; // 1 = Red, 0 = Green, -1 = Blue
39bool bLEDsActive = false;
40bool bLEDsBlink  = false;
41float fAverageTemp;
42float fAverageTempD;
43int iDeltaPositiveCount;
44bool  bInitAverage = true;
45int iAvgIndex;
46long lMilliSecondsSinceBeep = -1;
47long  iMilliSecondsSinceBeepCount = 50000;
48long iMilliSecondsSinceLastSwitchCount =  900000;
49long lMilliSecondsSinceLastSwitch = iMilliSecondsSinceLastSwitchCount;
50   
51void setup(void)
52{
53  // We'll send debugging information via the Serial  monitor
54  Serial.begin(9600);
55  Serial.println("Setup");  
56 
57  //  If you want to set the aref to something other than 5v
58  analogReference(EXTERNAL);
59  pinMode(iPinLedRed, OUTPUT);
60  pinMode(iPinLedGreen, OUTPUT);
61  pinMode(iPinLedBlue,  OUTPUT);
62
63  strSerialInput.reserve(20);
64
65  long lTop = EEPROMReadlong(iEEPROMTopTemperature);
66  if (lTop < 0 || lTop > 10000)
67  {
68    lTop = 4500;
69  }
70  long lBottom  = EEPROMReadlong(iEEPROMBottomTemperature);
71  if (lBottom < 0 || lBottom > 10000)
72  {
73    lBottom = 3900;
74  }
75
76  if (lTop < lBottom)
77  {
78    lTop  = 4500;
79    lBottom = 3900;
80  }
81  fTopTemperature = (float)lTop / (float)100;
82  fBottomTemperature = (float)lBottom / (float)100;
83  bTempDisplaysCelcius =  EEPROM.read(iEEPROMDisplayCelcius) == 1;
84  
85  bPlayTopTemperatureSound = EEPROM.read(iEEPROMPlayTopTemperatureSound)  == 1;
86  bPlayBottomTemperatureSound = EEPROM.read(iEEPROMPlayBottomTemperatureSound)  == 1;
87}
88 
89 
90void loop(void)
91{
92  if (bSerialInputComplete)
93  {
94    Serial.println(strSerialInput);
95    strSerialInput = "";
96    bSerialInputComplete  = false;
97  }
98  
99  iTemperatureReading = analogRead(iPinTemperature);  
100  // Converting temperature voltage to temperature using AREF
101  float fTemperatureVoltage  = iTemperatureReading * AREF;
102  fTemperatureVoltage /= 1024.0;
103  float fTemperatureC  = (fTemperatureVoltage - 0.5) * 100 ;  //converting from 10 mv per degree with 500  mV offset to degrees ((fTemperatureVoltage - 500mV) times 100
104
105  // Initialize  average arrays etc
106  if (bInitAverage)
107  {
108    for (int j = 0; j < AVGC;  j++)
109    {
110      fArrTemps[j] = fTemperatureC;
111      fArrTempsD[j] = (float)-0.01;
112    }
113    bInitAverage = false;
114    iAvgIndex = 0;
115    fAverageTemp = fTemperatureC;
116    fPreviousTemperature = fTemperatureC;
117    bLEDsActive = true;
118    lMilliSecondsSinceBeep  = millis();
119    iLEDConfigPrevious = -1;
120  }
121
122  // Point to next average  in the arrays
123  iAvgIndex++;
124  if (iAvgIndex > AVGC - 1)
125  {
126    iAvgIndex  = 0;
127  }
128
129  fArrTemps[iAvgIndex] = fTemperatureC;
130
131  // Calculate  averages
132  fAverageTemp = 0;
133  int iPosCount = 0;
134  for (int j = 0; j <  AVGC; j++)
135  {
136    if (fArrTempsD[j] > (float)0.0)
137    {
138      iPosCount++;
139    }
140    fAverageTemp += fArrTemps[j];
141    fAverageTempD += fArrTempsD[j];
142  }
143
144  fAverageTemp = fAverageTemp / (float)AVGC;
145  fAverageTempD = fAverageTempD  / (float)AVGC;
146 
147  Serial.print("[it:"); Serial.print(fTemperatureC);Serial.print(",tt:");
148  Serial.print(fTopTemperature);Serial.print(",bt:");
149  Serial.print(fBottomTemperature);Serial.print(",dc:");
150  Serial.print(bTempDisplaysCelcius);
151  Serial.print(",at:");Serial.print(fAverageTemp);
152  Serial.print(",pt:");Serial.print(bPlayTopTemperatureSound);
153  Serial.print(",pb:");Serial.print(bPlayBottomTemperatureSound);
154  Serial.println("]");
155
156  if (fAverageTemp >= fTopTemperature)
157  {
158    iLEDConfigCurrent = 1; // Red
159  }
160  if (fAverageTemp <= fBottomTemperature)
161  {
162    iLEDConfigCurrent = -1; // Blue
163  }
164  if (fAverageTemp > fBottomTemperature  && fAverageTemp < fTopTemperature)
165  {
166    iLEDConfigCurrent = 0; // Green
167  }
168
169  if (iLEDConfigCurrent >= 0 || (iLEDConfigCurrent == -1 && fAverageTempD  > 0 && iPosCount >= POSCOUNT))
170  {
171    lMilliSecondsSinceLastSwitch = millis();
172  }
173  
174  bLEDsActive = ((millis() - lMilliSecondsSinceLastSwitch) < iMilliSecondsSinceLastSwitchCount);
175
176  if (iLEDConfigPrevious == 1 && iLEDConfigCurrent == 0)
177  {
178      PlayUp();
179  }
180
181  if (iLEDConfigPrevious == 0 && iLEDConfigCurrent == -1)
182  {
183      PlayDown();
184  }
185
186  if (!bLEDsActive || (fAverageTempD > 0 && iPosCount  >= POSCOUNT && !bLEDsBlink))
187  {
188    digitalWrite(iPinLedRed, LOW);
189    digitalWrite(iPinLedGreen,  LOW);
190    digitalWrite(iPinLedBlue, LOW);
191  }
192  else
193  {
194    if (iLEDConfigCurrent  == 1)
195    {
196      digitalWrite(iPinLedRed, HIGH);
197      digitalWrite(iPinLedGreen,  LOW);
198      digitalWrite(iPinLedBlue, LOW);
199    }
200    if (iLEDConfigCurrent  == 0)
201    {
202      digitalWrite(iPinLedRed, LOW);
203      digitalWrite(iPinLedGreen,  HIGH);
204      digitalWrite(iPinLedBlue, LOW);
205    }
206    if (iLEDConfigCurrent  == -1)
207    {
208      digitalWrite(iPinLedRed, LOW);
209      digitalWrite(iPinLedGreen,  LOW);
210      digitalWrite(iPinLedBlue, HIGH);
211    }
212  }
213
214  fArrTempsD[iAvgIndex]  = fAverageTemp - fPreviousTemperature;
215  fPreviousTemperature = fAverageTemp;
216  iLEDConfigPrevious = iLEDConfigCurrent;
217  bLEDsBlink = !bLEDsBlink;
218  delay(450);
219}
220
221void  serialEvent()
222{
223  while (Serial.available())
224  {
225    // get the new  byte:
226    char inChar = (char)Serial.read();
227    // add it to the strSerialInput:
228    strSerialInput += inChar;
229    // if the incoming character is a newline,  set a flag so the main loop can
230    // do something about it:
231    if (inChar  == '\n')
232    {
233      bSerialInputComplete = true;
234
235      if (strSerialInput.startsWith("tt:"))
236      {
237          strSerialInput = strSerialInput.substring(3);
238          fTopTemperature  = strSerialInput.toFloat();
239          EEPROMWritelong(iEEPROMTopTemperature,  (long)(fTopTemperature * (float)100));
240      }
241
242      if (strSerialInput.startsWith("bt:"))
243      {
244          strSerialInput = strSerialInput.substring(3);
245          fBottomTemperature  = strSerialInput.toFloat();
246          EEPROMWritelong(iEEPROMBottomTemperature,  (long)(fBottomTemperature * (float)100));
247      }
248
249      bTempDisplaysCelcius  = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("dc:", bTempDisplaysCelcius,  iEEPROMDisplayCelcius);
250      bPlayTopTemperatureSound = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pt:",  bPlayTopTemperatureSound, iEEPROMPlayTopTemperatureSound);
251      bPlayBottomTemperatureSound  = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pb:", bPlayBottomTemperatureSound,  iEEPROMPlayBottomTemperatureSound);
252    }
253  }
254}
255
256bool ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool(String  ip_strCommand, bool ip_bOriginalValue, int ip_iEEPROM_Location)
257{
258  bool _bResult  = ip_bOriginalValue;
259  if (strSerialInput.startsWith(ip_strCommand))
260  {
261    strSerialInput = strSerialInput.substring(3);
262    _bResult = (strSerialInput  == "1\
263");
264    EEPROM.write(ip_iEEPROM_Location, _bResult);
265  }
266  return  _bResult;
267}
268
269void EEPROMWritelong(int address, long value)
270{
271  byte  by;
272  for(int i=0;i< 4;i++) {
273    by = (value >> ((3-i)*8)) & 0x000000ff;  
274    EEPROM.write(address+i, by);
275  }
276}
277
278
279long EEPROMReadlong(long  address)
280{
281  long lo=0;
282
283  for(int i=0;i< 3;i++){
284    lo += EEPROM.read(address+i);
285    lo = lo << 8;
286  }
287  lo += EEPROM.read(address+3);
288  return lo;
289}
290
291void  PlayUp()
292{
293  if (bPlayTopTemperatureSound && (millis() - lMilliSecondsSinceBeep  > iMilliSecondsSinceBeepCount))
294  { 
295    tone(iPinBuzzer, 440, 100);
296    delay(100);
297    tone(iPinBuzzer, 880, 100);
298    delay(100);
299    tone(iPinBuzzer, 1760,  100);
300    lMilliSecondsSinceBeep = millis();
301  }
302}
303
304void PlayDown()
305{
306  if (bPlayBottomTemperatureSound && (millis() - lMilliSecondsSinceBeep > iMilliSecondsSinceBeepCount))
307  { 
308    tone(iPinBuzzer, 1760, 100);
309    delay(100);
310    tone(iPinBuzzer,  880, 100);
311    delay(100);
312    tone(iPinBuzzer, 440, 100);
313    lMilliSecondsSinceBeep  = millis();
314  }
315}
316
317

#include <EEPROM.h>

#define AREF 3.3         // we tie 3.3V to  ARef and measure it with a multimeter!

//Vout TMP36 > A1
//3.3V > V+ TMP36  > AREF
//GND TMP36 > GND
//D6 > Piezo > GND
//D7 > Blue Led (+), Blue Led  (-) > 60 Ohm > GND
//D8 > Green Led (+), Green Led (-) > 560 Ohm > GND
//D9  > Red Led (+), Red Led (-) > 640 Ohm > GND

int iPinTemperature = 1;
int  iTemperatureReading;
int iPinLedRed = 9;
int iPinLedGreen = 8;
int iPinLedBlue  = 7;
int iPinBuzzer = 6;
String strSerialInput = "";
bool bSerialInputComplete  = false;
float fTopTemperature = 100;
float fBottomTemperature = 0;
int  iEEPROMTopTemperature = 0;
int iEEPROMBottomTemperature = 4;
int iEEPROMDisplayCelcius  = 8;
int iEEPROMPlayTopTemperatureSound = 9;
int iEEPROMPlayBottomTemperatureSound  = 10;
bool bPlayTopTemperatureSound = false;
bool bPlayBottomTemperatureSound  = false;
bool bTempDisplaysCelcius = true;
float fPreviousTemperature = 0;
//  Number of average temperatures in celcius
#define AVGC 13
#define POSCOUNT  10
float fArrTemps[AVGC]; // Array used to calculate the average temperature
float  fArrTempsD[AVGC]; // Array used to calculate the average delta temperature
int  iLEDConfigCurrent = 0; // 1 = Red, 0 = Green, -1 = Blue
int iLEDConfigPrevious  = 0; // 1 = Red, 0 = Green, -1 = Blue
bool bLEDsActive = false;
bool bLEDsBlink  = false;
float fAverageTemp;
float fAverageTempD;
int iDeltaPositiveCount;
bool  bInitAverage = true;
int iAvgIndex;
long lMilliSecondsSinceBeep = -1;
long  iMilliSecondsSinceBeepCount = 50000;
long iMilliSecondsSinceLastSwitchCount =  900000;
long lMilliSecondsSinceLastSwitch = iMilliSecondsSinceLastSwitchCount;
   
void setup(void)
{
  // We'll send debugging information via the Serial  monitor
  Serial.begin(9600);
  Serial.println("Setup");  
 
  //  If you want to set the aref to something other than 5v
  analogReference(EXTERNAL);
  pinMode(iPinLedRed, OUTPUT);
  pinMode(iPinLedGreen, OUTPUT);
  pinMode(iPinLedBlue,  OUTPUT);

  strSerialInput.reserve(20);

  long lTop = EEPROMReadlong(iEEPROMTopTemperature);
  if (lTop < 0 || lTop > 10000)
  {
    lTop = 4500;
  }
  long lBottom  = EEPROMReadlong(iEEPROMBottomTemperature);
  if (lBottom < 0 || lBottom > 10000)
  {
    lBottom = 3900;
  }

  if (lTop < lBottom)
  {
    lTop  = 4500;
    lBottom = 3900;
  }
  fTopTemperature = (float)lTop / (float)100;
  fBottomTemperature = (float)lBottom / (float)100;
  bTempDisplaysCelcius =  EEPROM.read(iEEPROMDisplayCelcius) == 1;
  
  bPlayTopTemperatureSound = EEPROM.read(iEEPROMPlayTopTemperatureSound)  == 1;
  bPlayBottomTemperatureSound = EEPROM.read(iEEPROMPlayBottomTemperatureSound)  == 1;
}
 
 
void loop(void)
{
  if (bSerialInputComplete)
  {
    Serial.println(strSerialInput);
    strSerialInput = "";
    bSerialInputComplete  = false;
  }
  
  iTemperatureReading = analogRead(iPinTemperature);  
  // Converting temperature voltage to temperature using AREF
  float fTemperatureVoltage  = iTemperatureReading * AREF;
  fTemperatureVoltage /= 1024.0;
  float fTemperatureC  = (fTemperatureVoltage - 0.5) * 100 ;  //converting from 10 mv per degree with 500  mV offset to degrees ((fTemperatureVoltage - 500mV) times 100

  // Initialize  average arrays etc
  if (bInitAverage)
  {
    for (int j = 0; j < AVGC;  j++)
    {
      fArrTemps[j] = fTemperatureC;
      fArrTempsD[j] = (float)-0.01;
    }
    bInitAverage = false;
    iAvgIndex = 0;
    fAverageTemp = fTemperatureC;
    fPreviousTemperature = fTemperatureC;
    bLEDsActive = true;
    lMilliSecondsSinceBeep  = millis();
    iLEDConfigPrevious = -1;
  }

  // Point to next average  in the arrays
  iAvgIndex++;
  if (iAvgIndex > AVGC - 1)
  {
    iAvgIndex  = 0;
  }

  fArrTemps[iAvgIndex] = fTemperatureC;

  // Calculate  averages
  fAverageTemp = 0;
  int iPosCount = 0;
  for (int j = 0; j <  AVGC; j++)
  {
    if (fArrTempsD[j] > (float)0.0)
    {
      iPosCount++;
    }
    fAverageTemp += fArrTemps[j];
    fAverageTempD += fArrTempsD[j];
  }

  fAverageTemp = fAverageTemp / (float)AVGC;
  fAverageTempD = fAverageTempD  / (float)AVGC;
 
  Serial.print("[it:"); Serial.print(fTemperatureC);Serial.print(",tt:");
  Serial.print(fTopTemperature);Serial.print(",bt:");
  Serial.print(fBottomTemperature);Serial.print(",dc:");
  Serial.print(bTempDisplaysCelcius);
  Serial.print(",at:");Serial.print(fAverageTemp);
  Serial.print(",pt:");Serial.print(bPlayTopTemperatureSound);
  Serial.print(",pb:");Serial.print(bPlayBottomTemperatureSound);
  Serial.println("]");

  if (fAverageTemp >= fTopTemperature)
  {
    iLEDConfigCurrent = 1; // Red
  }
  if (fAverageTemp <= fBottomTemperature)
  {
    iLEDConfigCurrent = -1; // Blue
  }
  if (fAverageTemp > fBottomTemperature  && fAverageTemp < fTopTemperature)
  {
    iLEDConfigCurrent = 0; // Green
  }

  if (iLEDConfigCurrent >= 0 || (iLEDConfigCurrent == -1 && fAverageTempD  > 0 && iPosCount >= POSCOUNT))
  {
    lMilliSecondsSinceLastSwitch = millis();
  }
  
  bLEDsActive = ((millis() - lMilliSecondsSinceLastSwitch) < iMilliSecondsSinceLastSwitchCount);

  if (iLEDConfigPrevious == 1 && iLEDConfigCurrent == 0)
  {
      PlayUp();
  }

  if (iLEDConfigPrevious == 0 && iLEDConfigCurrent == -1)
  {
      PlayDown();
  }

  if (!bLEDsActive || (fAverageTempD > 0 && iPosCount  >= POSCOUNT && !bLEDsBlink))
  {
    digitalWrite(iPinLedRed, LOW);
    digitalWrite(iPinLedGreen,  LOW);
    digitalWrite(iPinLedBlue, LOW);
  }
  else
  {
    if (iLEDConfigCurrent  == 1)
    {
      digitalWrite(iPinLedRed, HIGH);
      digitalWrite(iPinLedGreen,  LOW);
      digitalWrite(iPinLedBlue, LOW);
    }
    if (iLEDConfigCurrent  == 0)
    {
      digitalWrite(iPinLedRed, LOW);
      digitalWrite(iPinLedGreen,  HIGH);
      digitalWrite(iPinLedBlue, LOW);
    }
    if (iLEDConfigCurrent  == -1)
    {
      digitalWrite(iPinLedRed, LOW);
      digitalWrite(iPinLedGreen,  LOW);
      digitalWrite(iPinLedBlue, HIGH);
    }
  }

  fArrTempsD[iAvgIndex]  = fAverageTemp - fPreviousTemperature;
  fPreviousTemperature = fAverageTemp;
  iLEDConfigPrevious = iLEDConfigCurrent;
  bLEDsBlink = !bLEDsBlink;
  delay(450);
}

void  serialEvent()
{
  while (Serial.available())
  {
    // get the new  byte:
    char inChar = (char)Serial.read();
    // add it to the strSerialInput:
    strSerialInput += inChar;
    // if the incoming character is a newline,  set a flag so the main loop can
    // do something about it:
    if (inChar  == '\n')
    {
      bSerialInputComplete = true;

      if (strSerialInput.startsWith("tt:"))
      {
          strSerialInput = strSerialInput.substring(3);
          fTopTemperature  = strSerialInput.toFloat();
          EEPROMWritelong(iEEPROMTopTemperature,  (long)(fTopTemperature * (float)100));
      }

      if (strSerialInput.startsWith("bt:"))
      {
          strSerialInput = strSerialInput.substring(3);
          fBottomTemperature  = strSerialInput.toFloat();
          EEPROMWritelong(iEEPROMBottomTemperature,  (long)(fBottomTemperature * (float)100));
      }

      bTempDisplaysCelcius  = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("dc:", bTempDisplaysCelcius,  iEEPROMDisplayCelcius);
      bPlayTopTemperatureSound = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pt:",  bPlayTopTemperatureSound, iEEPROMPlayTopTemperatureSound);
      bPlayBottomTemperatureSound  = ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool("pb:", bPlayBottomTemperatureSound,  iEEPROMPlayBottomTemperatureSound);
    }
  }
}

bool ParseSerialOfBoolIfMatchSetEEPROMAndReturnBool(String  ip_strCommand, bool ip_bOriginalValue, int ip_iEEPROM_Location)
{
  bool _bResult  = ip_bOriginalValue;
  if (strSerialInput.startsWith(ip_strCommand))
  {
    strSerialInput = strSerialInput.substring(3);
    _bResult = (strSerialInput  == "1\
");
    EEPROM.write(ip_iEEPROM_Location, _bResult);
  }
  return  _bResult;
}

void EEPROMWritelong(int address, long value)
{
  byte  by;
  for(int i=0;i< 4;i++) {
    by = (value >> ((3-i)*8)) & 0x000000ff;  
    EEPROM.write(address+i, by);
  }
}


long EEPROMReadlong(long  address)
{
  long lo=0;

  for(int i=0;i< 3;i++){
    lo += EEPROM.read(address+i);
    lo = lo << 8;
  }
  lo += EEPROM.read(address+3);
  return lo;
}

void  PlayUp()
{
  if (bPlayTopTemperatureSound && (millis() - lMilliSecondsSinceBeep  > iMilliSecondsSinceBeepCount))
  { 
    tone(iPinBuzzer, 440, 100);
    delay(100);
    tone(iPinBuzzer, 880, 100);
    delay(100);
    tone(iPinBuzzer, 1760,  100);
    lMilliSecondsSinceBeep = millis();
  }
}

void PlayDown()
{
  if (bPlayBottomTemperatureSound && (millis() - lMilliSecondsSinceBeep > iMilliSecondsSinceBeepCount))
  { 
    tone(iPinBuzzer, 1760, 100);
    delay(100);
    tone(iPinBuzzer,  880, 100);
    delay(100);
    tone(iPinBuzzer, 440, 100);
    lMilliSecondsSinceBeep  = millis();
  }
}

Downloadable files

Circuit Diagram

Diagram of the circuit

Circuit Diagram

Bread Board Layout

Before putting together you can try on a breadboard

Bread Board Layout

Circuit Diagram

Diagram of the circuit

Circuit Diagram

Bread Board Layout

Before putting together you can try on a breadboard

Bread Board Layout

Documentation

STL of the holder of the thermometer