# LAB09 自動降溫控制
## DEMO
<iframe width="560" height="315" src="https://www.youtube.com/embed/Dh5zqItUowA?si=WRT53tQFTmeiFQRc" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>

## 電路圖

## 程式碼
- 處理按鈕的任務

    void buttonTask(void *pvParameters) {
        while (true) {
            // 切換模式按鈕
            switch (change.check()) {
                case Switch::RELEASED_FROM_PRESS:
                case Switch::PRESSING:
                    settingMode = !settingMode; 
                    break;
            }

            // 增加按鈕
            if (settingMode) {
                switch (inc.check()) {
                    case Switch::RELEASED_FROM_PRESS:
                    case Switch::PRESSING:
                        thresholdTemp++;
                        if (thresholdTemp > 35){ 
                            thresholdTemp = 35;
                        }
                        break;
                }
            }

            // 減少按鈕
            if (settingMode) {
                switch (dec.check()) {
                    case Switch::RELEASED_FROM_PRESS:
                    case Switch::PRESSING:
                        thresholdTemp--;
                        if (thresholdTemp < 20){ 
                            thresholdTemp = 20;
                        }
                        break;
                }
            }


        }
    }

- 處理溫度的程式
- 熱敏電阻的處理

        const float ntcResistance = 10000.0; // NTC的標稱電阻值 (10kΩ)
        const float nominalTemperature = 25.0; // NTC的標稱溫度 (25°C)
        const float betaValue = 3950.0; // NTC的Beta值 (通常為3950)

        int rawValue = analogRead(ntcPin);

        // 計算NTC的電阻值
        float resistance = ntcResistance / (4095.0 / rawValue - 1.0);

        // 計算溫度（攝氏度）
        float steinhart = resistance / ntcResistance; // 計算Steinhart-Hart公式的中間值
        steinhart = log(steinhart); // 自然對數
        steinhart /= betaValue; // 除以Beta值
        steinhart += 1.0 / (nominalTemperature + 273.15); // 加上(1 / T0)
        steinhart = 1.0 / steinhart; // 取倒數，得到溫度（Kelvin）
        steinhart -= 273.15; // 轉換為攝氏度

- 繼電器的程式

    void fanTask(void *pvParameters) {
        while (true) {
            if (temperature > thresholdTemp) {
                digitalWrite(relayPin, HIGH); // 啟動繼電器
            } 
            else {
                digitalWrite(relayPin, LOW);  // 關閉繼電器
            }

        }
    }

- OLED輸出

    u8g2.firstPage();
    do {
        String msg;
        msg = "溫度   : " + String((float)temperature, 1) + " °C";
        u8g2.setCursor(0, 20);
        u8g2.print(msg.c_str());

        msg = "臨界值 : " + String((int)thresholdTemp) + " °C";   
        u8g2.setCursor(0, 40);  
        u8g2.print(msg.c_str());

        // 顯示設定模式狀態
        msg = "Mode: " + (settingMode ? String("Open") : String("Close")) ;
        u8g2.setCursor(0, 60);
        u8g2.print(msg.c_str());
    } while (u8g2.nextPage());

## 程式碼

#include <U8g2lib.h>
#include <SimpleDHT.h>
#include <switch.h>
#include <freertos/FreeRTOS.h>
#include <freertos/task.h>


// 設定OLED的數值
#define SCREEN_WIDTH 128     
#define SCREEN_HEIGHT 64     
#define OLED_RESET -1       

// 設定各PIN腳
#define pinNTC 4
#define incSwitchPin 27
#define decSwitchPin 26
#define modeSwitchPin 25  
#define relayPin 17      

// 全域變數供個任務使用
int thresholdTemp = 25;      
float temperature = 0;
bool settingMode = false;    


Switch inc(incSwitchPin, LOW, true);
Switch dec(decSwitchPin, LOW, true);
Switch change(modeSwitchPin, LOW, true);
U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, U8X8_PIN_NONE);

//按鈕處理任務
void buttonTask(void *pvParameters) {
    while (true) {
        
        // 切換模式按鈕
        switch (change.check()) {
            case Switch::RELEASED_FROM_PRESS:
            case Switch::PRESSING:
                settingMode = !settingMode; 
                break;
        }

        // 增加按鈕
        if (settingMode) {
            switch (inc.check()) {
                case Switch::RELEASED_FROM_PRESS:
                case Switch::PRESSING:
                    thresholdTemp++;
                    if (thresholdTemp > 35){ 
                        thresholdTemp = 35;
                    }
                    break;
            }
        }

        // 減少按鈕
        if (settingMode) {
            switch (dec.check()) {
                case Switch::RELEASED_FROM_PRESS:
                case Switch::PRESSING:
                    thresholdTemp--;
                    if (thresholdTemp < 20){ 
                        thresholdTemp = 20;
                    }
                    break;
            }
        }

    
    }
}


void NTCTask(void *pvParameters){
    const static float ntcResistance = 10000.0; 
    const static float nominalTemperature = 25.0; 
    const static float betaValue = 3950.0; 
    while(true){
        int rawValue = analogRead(pinNTC);
        if (rawValue == 0) {
            continue;
        }
        float resistance = ntcResistance / (4095.0 / rawValue - 1.0);
        
        float steinhart = resistance / ntcResistance; 
        steinhart = log(steinhart); 
        steinhart /= betaValue; 
        steinhart += 1.0 / (nominalTemperature + 273.15); 
        steinhart = 1.0 / steinhart; 
        steinhart -= 273.15; 
        
        temperature = steinhart;
        
    }
    
}
// 風扇控制任務
void fanTask(void *pvParameters) {
    while (true) {
        if (temperature > thresholdTemp) {
            digitalWrite(relayPin, HIGH); // 啟動繼電器
        } 
        else {
            digitalWrite(relayPin, LOW);  // 關閉繼電器
        }
        
    }
}

// 更新 OLED 顯示
void displayInfo() {
    u8g2.firstPage();
    do {
        String msg;
        msg = "溫度   : " + String((float)temperature, 1) + " °C";
        u8g2.setCursor(0, 20);
        u8g2.print(msg.c_str());

        msg = "臨界值 : " + String((int)thresholdTemp) + " °C";   
        u8g2.setCursor(0, 40);  
        u8g2.print(msg.c_str());

        // 顯示設定模式狀態
        msg = "Mode: " + (settingMode ? String("Open") : String("Close")) ;
        u8g2.setCursor(0, 60);
        u8g2.print(msg.c_str());
    } while (u8g2.nextPage());
    
 }

void setup() {
    Serial.begin(9600);
    
    u8g2.begin();
    u8g2.enableUTF8Print();
    u8g2.setFont(u8g2_font_unifont_t_chinese1);

    pinMode(relayPin, OUTPUT);

    digitalWrite(relayPin, LOW); 
    
    xTaskCreate(buttonTask, "Button Task", 1024, NULL, 1, NULL);
    xTaskCreate(NTCTask, "DHT11 Task", 1024, NULL, 0, NULL);
    xTaskCreate(fanTask, "Fan Task", 1024, NULL, 0, NULL);
}
void loop() {

    
    displayInfo();
    delay(100);
}