Refactor

- Source files moved to src/
- operame.cpp renamed to main.cpp
- Display code factored out to separate file
- Sensor code factored out to separate file, turned into classes

.gitignore

@@ -1,2 +1,2 @@
-.pio
+.*
 platformio-*.ini

src/display.h

@@ -0,0 +1,62 @@
+#include <Arduino.h>
+#include <WiFi.h>
+#include <SPI.h>
+#include <TFT_eSPI.h>
+#include <src/logo.h>
+#include <list>
+
+TFT_eSPI        tft;
+TFT_eSprite     sprite(&tft);
+
+void clear_sprite(int bg = TFT_BLACK) {
+    sprite.fillSprite(bg);
+    if (WiFi.status() == WL_CONNECTED) {
+        sprite.drawRect(0, 0, tft.width(), tft.height(), TFT_BLUE);
+    }
+}
+
+void display(const String& text, int fg = TFT_WHITE, int bg = TFT_BLACK) {
+    clear_sprite(bg);
+    sprite.setTextSize(1);
+    bool nondigits = false;
+    for (int i = 0; i < text.length(); i++) {
+        char c = text.charAt(i);
+        if (c < '0' || c > '9') nondigits = true;
+    }
+    sprite.setTextFont(nondigits ? 4 : 8);
+    sprite.setTextSize(nondigits && text.length() < 10 ? 2 : 1);
+    sprite.setTextDatum(MC_DATUM);
+    sprite.setTextColor(fg, bg);
+    sprite.drawString(text, tft.width()/2, tft.height()/2);
+
+    sprite.pushSprite(0, 0);
+}
+
+void display(const std::list<String>& lines, int fg = TFT_WHITE, int bg = TFT_BLACK) {
+    clear_sprite(bg);
+    sprite.setTextSize(1);
+    sprite.setTextFont(4);
+    sprite.setTextDatum(MC_DATUM);
+    sprite.setTextColor(fg, bg);
+
+    const int line_height = 32;
+    int y = tft.height()/2 - (lines.size()-1) * line_height/2;
+    for (auto line : lines) {
+        sprite.drawString(line, tft.width()/2, y);
+        y += line_height;
+    }
+    sprite.pushSprite(0, 0);
+}
+
+void display_logo() {
+    clear_sprite();
+    sprite.setSwapBytes(true);
+    sprite.pushImage(12, 30, 215, 76, OPERAME_LOGO);
+    sprite.pushSprite(0, 0);
+}
+
+void panic(const String& message) {
+    display(message, TFT_RED);
+    delay(5000);
+    ESP.restart();
+}

src/main.cpp

@@ -3,24 +3,17 @@
 #include <MQTT.h>
 #include <SPIFFS.h>
 #include <WiFiSettings.h>
-#include <MHZ19.h>
 #include <ArduinoOTA.h>
-#include <SPI.h>
+#include <src/strings.h>
-#include <TFT_eSPI.h>
+#include <src/display.h>
-#include <logo.h>
+#include <src/sensors.h>
-#include <list>
-#include <operame_strings.h>
 
 #define LANGUAGE "nl"
 OperameLanguage::Texts T;
 
-enum Driver { AQC, MHZ };
-Driver          driver;
 MQTTClient      mqtt;
 HardwareSerial  hwserial1(1);
-TFT_eSPI        display;
+CO2Sensor       *sensor;
-TFT_eSprite     sprite(&display);
-MHZ19           mhz;
 
 const int       pin_portalbutton = 35;
 const int       pin_demobutton   = 0;
@@ -28,7 +21,6 @@ const int       pin_backlight    = 4;
 const int       pin_sensor_rx    = 27;
 const int       pin_sensor_tx    = 26;
 const int       pin_pcb_ok       = 12;   // pulled to GND by PCB trace
-int             mhz_co2_init     = 410;  // magic value reported during init
 
 // Configuration via WiFiSettings
 unsigned long   mqtt_interval;
@@ -43,51 +35,32 @@ bool            wifi_enabled;
 bool            mqtt_enabled;
 int             max_failures;
 
-void clear_sprite(int bg = TFT_BLACK) {
+bool button(int pin) {
-    sprite.fillSprite(bg);
+    if (digitalRead(pin)) return false;
-    if (WiFi.status() == WL_CONNECTED) {
+    unsigned long start = millis();
-        sprite.drawRect(0, 0, display.width(), display.height(), TFT_BLUE);
+    while (!digitalRead(pin)) {
+        if (millis() - start >= 50) display("");
     }
+    return millis() - start >= 50;
 }
 
-void display_big(const String& text, int fg = TFT_WHITE, int bg = TFT_BLACK) {
+void calibrate() {
-    clear_sprite(bg);
+    auto lines = T.calibration;
-    sprite.setTextSize(1);
+    for (int count = 60; count >= 0; count--) {
-    bool nondigits = false;
+        lines.back() = String(count);
-    for (int i = 0; i < text.length(); i++) {
+        display(lines, TFT_RED);
-        char c = text.charAt(i);
+        unsigned long start = millis();
-        if (c < '0' || c > '9') nondigits = true;
+        while (millis() - start < 1000) {
+            if (button(pin_demobutton) || button(pin_portalbutton)) return;
         }
-    sprite.setTextFont(nondigits ? 4 : 8);
-    sprite.setTextSize(nondigits && text.length() < 10 ? 2 : 1);
-    sprite.setTextDatum(MC_DATUM);
-    sprite.setTextColor(fg, bg);
-    sprite.drawString(text, display.width()/2, display.height()/2);
-
-    sprite.pushSprite(0, 0);
-}
-
-void display_lines(const std::list<String>& lines, int fg = TFT_WHITE, int bg = TFT_BLACK) {
-    clear_sprite(bg);
-    sprite.setTextSize(1);
-    sprite.setTextFont(4);
-    sprite.setTextDatum(MC_DATUM);
-    sprite.setTextColor(fg, bg);
-
-    const int line_height = 32;
-    int y = display.height()/2 - (lines.size()-1) * line_height/2;
-    for (auto line : lines) {
-        sprite.drawString(line, display.width()/2, y);
-        y += line_height;
     }
-    sprite.pushSprite(0, 0);
-}
 
-void display_logo() {
+    lines = T.calibrating;
-    clear_sprite();
+    for (auto& line : lines) line.replace("400", String(sensor->co2_zero));
-    sprite.setSwapBytes(true);
+    display(lines, TFT_MAGENTA);
-    sprite.pushImage(12, 30, 215, 76, OPERAME_LOGO);
+
-    sprite.pushSprite(0, 0);
+    sensor->set_zero();  // actually instantaneous
+    delay(15000);  // give time to read long message
 }
 
 void display_ppm(int ppm) {
@@ -106,148 +79,11 @@ void display_ppm(int ppm) {
     if (ppm >= co2_blink && millis() % 2000 < 1000) {
         std::swap(fg, bg);
     }
-    display_big(String(ppm), fg, bg);
+    display(String(ppm), fg, bg);
-}
-
-void panic(const String& message) {
-    display_big(message, TFT_RED);
-    delay(5000);
-    ESP.restart();
-}
-
-bool button(int pin) {
-    if (digitalRead(pin)) return false;
-    unsigned long start = millis();
-    while (!digitalRead(pin)) {
-        if (millis() - start >= 50) display_big("");
-    }
-    return millis() - start >= 50;
-}
-
-void flush(Stream& s, int limit = 20) {
-    // .available() sometimes stays true (why?), hence the limit
-
-    s.flush();  // flush output
-    while(s.available() && --limit) s.read();  // flush input
-}
-
-int aqc_get_co2() {
-    static bool initialized = false;
-
-    const uint8_t command[9] = { 0xff, 0x01, 0xc5, 0, 0, 0, 0, 0, 0x3a };
-    uint8_t response[9];
-    int co2 = -1;
-
-    for (int attempt = 0; attempt < 3; attempt++) {
-        flush(hwserial1);
-        hwserial1.write(command, sizeof(command));
-        delay(50);
-
-        size_t c = hwserial1.readBytes(response, sizeof(response));
-        if (c != sizeof(response) || response[0] != 0xff || response[1] != 0x86) {
-            continue;
-        }
-        uint8_t checksum = 255;
-        for (int i = 0; i < sizeof(response) - 1; i++) {
-            checksum -= response[i];
-        }
-        if (response[8] == checksum) {
-            co2 = response[2] * 256 + response[3];
-            break;
-        }
-        delay(50);
-    }
-
-    if (co2 < 0) {
-        initialized = false;
-        return co2;
-    }
-
-    if (!initialized && (co2 == 9999 || co2 == 400)) return 0;
-    initialized = true;
-    return co2;
-}
-
-void aqc_set_zero() {
-    const uint8_t command[9] = { 0xff, 0x01, 0x87, 0, 0, 0, 0, 0, 0x78 };
-    flush(hwserial1);
-    hwserial1.write(command, sizeof(command));
-}
-
-void mhz_setup() {
-    mhz.begin(hwserial1);
-    // mhz.setFilter(true, true);  Library filter doesn't handle 0436
-    mhz.autoCalibration(true);
-    char v[5] = {};
-    mhz.getVersion(v);
-    v[4] = '\0';
-    if (strcmp("0436", v) == 0) mhz_co2_init = 436;
-}
-
-int mhz_get_co2() {
-    int co2       = mhz.getCO2();
-    int unclamped = mhz.getCO2(false);
-
-    if (mhz.errorCode != RESULT_OK) {
-        delay(500);
-        mhz_setup();
-        return -1;
-    }
-
-    // reimplement filter from library, but also checking for 436 because our
-    // sensors (firmware 0436, coincidence?) return that instead of 410...
-    if (unclamped == mhz_co2_init && co2 - unclamped >= 10) return 0;
-
-    // No known sensors support >10k PPM (library filter tests for >32767)
-    if (co2 > 10000 || unclamped > 10000) return 0;
-
-    return co2;
-}
-
-void mhz_set_zero() {
-    mhz.calibrate();
-}
-
-int get_co2() {
-    // <0 means read error, 0 means still initializing, >0 is PPM value
-
-    if (driver == AQC) return aqc_get_co2();
-    if (driver == MHZ) return mhz_get_co2();
-
-    // Should be unreachable
-    panic(T.error_driver);
-    return -1;  // suppress warning
-}
-
-void set_zero() {
-    if (driver == AQC) { aqc_set_zero(); return; }
-    if (driver == MHZ) { mhz_set_zero(); return; }
-
-    // Should be unreachable
-    panic(T.error_driver);
-}
-
-void calibrate() {
-    auto lines = T.calibration;
-    for (int count = 60; count >= 0; count--) {
-        lines.back() = String(count);
-        display_lines(lines, TFT_RED);
-        unsigned long start = millis();
-        while (millis() - start < 1000) {
-            if (button(pin_demobutton) || button(pin_portalbutton)) return;
-        }
-    }
-
-    lines = T.calibrating;
-    if (driver == AQC) for (auto& line : lines) line.replace("400", "425");
-    display_lines(lines, TFT_MAGENTA);
-
-    set_zero();    // actually instantaneous
-    delay(15000);  // give time to read long message
 }
 
 void ppm_demo() {
-    display_big("demo!");
+    display("demo!");
     delay(3000);
     display_logo();
     delay(1000);
@@ -285,20 +121,15 @@ void check_demobutton() {
     if (button(pin_demobutton)) ppm_demo();
 }
 
-void check_buttons() {
-    check_portalbutton();
-    check_demobutton();
-}
-
 void setup_ota() {
     ArduinoOTA.setHostname(WiFiSettings.hostname.c_str());
     ArduinoOTA.setPassword(WiFiSettings.password.c_str());
-    ArduinoOTA.onStart(   []()              { display_big("OTA", TFT_BLUE); });
+    ArduinoOTA.onStart(   []()              { display("OTA", TFT_BLUE); });
-    ArduinoOTA.onEnd(     []()              { display_big("OTA done", TFT_GREEN); });
+    ArduinoOTA.onEnd(     []()              { display("OTA done", TFT_GREEN); });
-    ArduinoOTA.onError(   [](ota_error_t e) { display_big("OTA failed", TFT_RED); });
+    ArduinoOTA.onError(   [](ota_error_t e) { display("OTA failed", TFT_RED); });
     ArduinoOTA.onProgress([](unsigned int p, unsigned int t) {
         String pct { (int) ((float) p / t * 100) };
-        display_big(pct + "%");
+        display(pct + "%");
     });
     ArduinoOTA.begin();
 }
@@ -325,17 +156,17 @@ void setup() {
     Serial.println("Operame start");
 
     digitalWrite(pin_backlight, HIGH);
-    display.init();
+    tft.init();
-    display.fillScreen(TFT_BLACK);
+    tft.fillScreen(TFT_BLACK);
-    display.setRotation(1);
+    tft.setRotation(1);
-    sprite.createSprite(display.width(), display.height());
+    sprite.createSprite(tft.width(), tft.height());
 
     OperameLanguage::select(T, LANGUAGE);
 
     if (!SPIFFS.begin(false)) {
-        display_lines(T.first_run, TFT_MAGENTA);
+        display(T.first_run, TFT_MAGENTA);
         if (!SPIFFS.format()) {
-            display_big(T.error_format, TFT_RED);
+            display(T.error_format, TFT_RED);
             delay(20*1000);
         }
     }
@@ -351,7 +182,7 @@ void setup() {
     OperameLanguage::select(T, WiFiSettings.language);
 
     while (digitalRead(pin_pcb_ok)) {
-        display_big(T.error_module, TFT_RED);
+        display(T.error_module, TFT_RED);
         delay(1000);
     }
 
@@ -360,17 +191,18 @@ void setup() {
 
     hwserial1.begin(9600, SERIAL_8N1, pin_sensor_rx, pin_sensor_tx);
 
-    if (aqc_get_co2() >= 0) {
+    sensor = new AQC(&hwserial1);
-        driver = AQC;
+    sensor->begin();
+    if (sensor->get_co2() >= 0) {
         hwserial1.setTimeout(100);
         Serial.println("Using AQC driver.");
     } else {
-        driver = MHZ;
+        delete sensor;
-        mhz_setup();
+        sensor = new MHZ(&hwserial1);
+        sensor->begin();
         Serial.println("Using MHZ driver.");
     }
 
-
     for (auto& str : T.portal_instructions[0]) {
         str.replace("{ssid}", WiFiSettings.hostname);
     }
@@ -394,12 +226,12 @@ void setup() {
     WiFiSettings.info(T.config_template_info);
 
     WiFiSettings.onConnect = [] {
-        display_big(T.connecting, TFT_BLUE);
+        display(T.connecting, TFT_BLUE);
         check_portalbutton();
         return 50;
     };
     WiFiSettings.onFailure = [] {
-        display_big(T.error_wifi, TFT_RED);
+        display(T.error_wifi, TFT_RED);
         delay(2000);
     };
     static int portal_phase = 0;
@@ -418,7 +250,7 @@ void setup() {
         if (WiFi.softAPgetStationNum() == 0) portal_phase = 0;
         else if (! portal_phase) portal_phase = 1;
 
-        display_lines(T.portal_instructions[portal_phase], TFT_WHITE, TFT_BLUE);
+        display(T.portal_instructions[portal_phase], TFT_WHITE, TFT_BLUE);
 
         if (portal_phase == 0 && millis() - portal_start > 10*60*1000) {
             panic(T.error_timeout);
@@ -442,15 +274,15 @@ void loop() {
     static int co2;
 
     every(5000) {
-        co2 = get_co2();
+        co2 = sensor->get_co2();
         Serial.println(co2);
     }
 
     every(50) {
         if (co2 < 0) {
-            display_big(T.error_sensor, TFT_RED);
+            display(T.error_sensor, TFT_RED);
         } else if (co2 == 0) {
-            display_big(T.wait);
+            display(T.wait);
         } else {
             // some MH-Z19's go to 10000 but the display has space for 4 digits
             display_ppm(co2 > 9999 ? 9999 : co2);
@@ -469,5 +301,7 @@ void loop() {
     }
 
     if (ota_enabled) ArduinoOTA.handle();
-    check_buttons();
+
+    check_portalbutton();
+    check_demobutton();
 }

src/sensors.h

@@ -0,0 +1,113 @@
+#include <Arduino.h>
+#include <MHZ19.h>
+
+struct CO2Sensor {
+    int co2_zero;
+    virtual ~CO2Sensor() = default;
+    virtual void begin() = 0;
+    virtual void set_zero() = 0;
+    virtual int get_co2() = 0;
+    // <0 means read error, 0 means still initializing, >0 is PPM value
+};
+
+struct AQC : CO2Sensor {
+    int co2_zero = 425;
+    
+    Stream *serial;
+    AQC(Stream *x) : serial(x) {}
+
+    void flush(int limit = 20) {
+        // .available() sometimes stays true (why?), hence the limit
+
+        serial->flush();  // flush output
+        while(serial->available() && --limit) serial->read();  // flush input
+    }
+
+    void begin() { }
+
+    int get_co2() {
+        static bool initialized = false;
+
+        const uint8_t command[9] = { 0xff, 0x01, 0xc5, 0, 0, 0, 0, 0, 0x3a };
+        uint8_t response[9];
+        int co2 = -1;
+
+        for (int attempt = 0; attempt < 3; attempt++) {
+            flush();
+            serial->write(command, sizeof(command));
+            delay(50);
+
+            size_t c = serial->readBytes(response, sizeof(response));
+            if (c != sizeof(response) || response[0] != 0xff || response[1] != 0x86) {
+                continue;
+            }
+            uint8_t checksum = 255;
+            for (int i = 0; i < sizeof(response) - 1; i++) {
+                checksum -= response[i];
+            }
+            if (response[8] == checksum) {
+                co2 = response[2] * 256 + response[3];
+                break;
+            }
+            delay(50);
+        }
+
+        if (co2 < 0) {
+            initialized = false;
+            return co2;
+        }
+
+        if (!initialized && (co2 == 9999 || co2 == 400)) return 0;
+        initialized = true;
+        return co2;
+    }
+
+    void set_zero() {
+        const uint8_t command[9] = { 0xff, 0x01, 0x87, 0, 0, 0, 0, 0, 0x78 };
+        flush();
+        serial->write(command, sizeof(command));
+    }
+};
+
+struct MHZ : CO2Sensor {
+    MHZ19 mhz;
+    int co2_zero = 400;
+    int co2_init = 410;
+    
+    Stream *serial;
+    MHZ(Stream *x) : serial(x) {}
+
+    void begin() {
+        mhz.begin(*serial);
+        // mhz.setFilter(true, true);  Library filter doesn't handle 0436
+        mhz.autoCalibration(true);
+        char v[5] = {};
+        mhz.getVersion(v);
+        v[4] = '\0';
+        if (strcmp("0436", v) == 0) co2_init = 436;
+    }
+
+    int get_co2() {
+        int co2       = mhz.getCO2();
+        int unclamped = mhz.getCO2(false);
+
+        if (mhz.errorCode != RESULT_OK) {
+            delay(500);
+            setup();
+            return -1;
+        }
+
+        // reimplement filter from library, but also checking for 436 because our
+        // sensors (firmware 0436, coincidence?) return that instead of 410...
+        if (unclamped == co2_init && co2 - unclamped >= 10) return 0;
+
+        // No known sensors support >10k PPM (library filter tests for >32767)
+        if (co2 > 10000 || unclamped > 10000) return 0;
+
+        return co2;
+    }
+
+    void set_zero() {
+        mhz.calibrate();
+    }
+};

src/strings.h

@@ -1,3 +1,4 @@
+#include <Arduino.h>
 #include <map>
 #include <vector>
 #include <list>