Merge pull request #32 from davidkreidler/lowEnergyMode

v5.7 Low Energy Mode (50 days runtime):
- Change the refresh rate in Battery mode to every 5 min via the Menu -> Display -> Update (5min). This will exend Battery life to about 50 days.
Plotly colors and font size:
- Use dark green for the CO2 title and Graph. Also fill the area below. 
- Use red for Temperature and blue for Humidity.
- The GitHub version link now opens a new tab.

Author: davidkreidler

OpenCO2_Sensor.ino

@@ -10,12 +10,13 @@
    - WiFiManager: https://github.com/tzapu/WiFiManager
    - ArduinoMqttClient (if MQTT is defined)
 */
-#define VERSION "v5.6"
+#define VERSION "v5.7"
 
 #define HEIGHT_ABOVE_SEA_LEVEL 50             // Berlin
 #define TZ_DATA "CET-1CEST,M3.5.0,M10.5.0/3"  // Europe/Berlin time zone from https://github.com/nayarsystems/posix_tz_db/blob/master/zones.csv
 #define LIGHT_SLEEP_TIME 500
-#define DEEP_SLEEP_TIME 29124
+#define DEEP_SLEEP_TIME 29124             // 30 sec
+#define LOW_ENERGY_DEEP_SLEEP_TIME 287924 // 5 min
 #define DEEP_SLEEP_TIME_NO_DISPLAY_UPDATE DEEP_SLEEP_TIME + 965 // offset for no display update
 static unsigned long lastMeasurementTimeMs = 0;
 
@@ -86,7 +87,7 @@ SensirionI2cScd4x scd4x;
 USBMSC usbmsc;
 
 RTC_DATA_ATTR bool USB_ACTIVE = false, initDone = false, BatteryMode = false, comingFromDeepSleep = false;
-RTC_DATA_ATTR bool LEDonBattery, LEDonUSB, useSmoothLEDcolor, invertDisplay, useFahrenheit, useWiFi, english;
+RTC_DATA_ATTR bool LEDonBattery, LEDonUSB, useSmoothLEDcolor, invertDisplay, useFahrenheit, useWiFi, lowEnergyMode, english;
 RTC_DATA_ATTR uint8_t ledbrightness, HWSubRev, font;
 RTC_DATA_ATTR float maxBatteryVoltage;
 
@@ -196,7 +197,7 @@ void HandleRootClient() {
   message += "<div id='CO2Plot' style='width:100%;max-width:1400px'></div>\n";
   message += "<div id='TempHumPlot' style='width:100%;max-width:1400px'></div>\n";
 
-  message += "<a href='https://github.com/davidkreidler/OpenCO2_Sensor/releases'>Installed Version: ";
+  message += "<a target='_blank' rel='noopener noreferrer' href='https://github.com/davidkreidler/OpenCO2_Sensor/releases'>Installed Version: ";
   message += VERSION;
   message += "</a>\n";
   message += "<script>\n";
@@ -236,8 +237,8 @@ void HandleRootClient() {
   server.sendContent(Buffer);
 
   message = "];\n";
-  message += "const data = [{x:times, y:yValues, mode:'lines'}];\n";
-  message += "const layout = {yaxis: { title: 'CO2 (ppm)'}, title: 'History', plot_bgcolor:'black', paper_bgcolor:'black'};\n";
+  message += "const data = [{x:times, y:yValues, mode:'lines', fill: 'tonexty', fillcolor: 'rgba(0, 100, 00, 0.3)', line: {color: '#006400'}}];\n";
+  message += "const layout = {yaxis: {range: [Math.min(...data[0].y), Math.max(...data[0].y) * 1.05], title: {text: 'CO2 (ppm)', font: { color: '#006400',size: 20}}}, title: {text: 'History', font: { color: '#808080', size: 40}}, plot_bgcolor:'black', paper_bgcolor:'black'};\n";
   message += "Plotly.newPlot('CO2Plot', data, layout);\n";
   server.sendContent(message);
 
@@ -268,10 +269,9 @@ void HandleRootClient() {
 
   message = "];\nconst numPoints2 = " + String(index) + ";\n";
   message += "let times2 = generateValues(startTime, endTime, numPoints2).map(time => new Date(time));\n";
-  message += "const data2 = [{x: times2, y: y1Values, name: 'Temperature', mode:'lines'}, ";
-  message += "{x: times2, y: y2Values, name: 'Humidity', yaxis: 'y2', mode:'lines'}];\n";
-  message += "const layout2 = { showlegend: false, yaxis: {title: 'Temperature (" + String(useFahrenheit? "*F" : "*C") ;
-  message += ")'}, yaxis2: { title: 'Humidity (%)', overlaying: 'y', side: 'right'}, plot_bgcolor:'black', paper_bgcolor:'black'};\n";
+  message += "const data2 = [{x: times2, y: y1Values, name: 'Temperature', line: { color: '#FF4500' }, mode:'lines'}, {x: times2, y: y2Values, name: 'Humidity', line: { color: '#1E90FF' }, yaxis: 'y2', mode:'lines'}];\n";
+  message += "const layout2 = { showlegend: false, yaxis: {title: {text: 'Temperature (*" + String(useFahrenheit? "F" : "C");
+  message += ")', font: { color: '#FF4500',size: 20}}}, yaxis2: {title: {text: 'Humidity (%)', font: { color: '#1E90FF',size: 20}}, overlaying: 'y', side: 'right'}, plot_bgcolor:'black', paper_bgcolor:'black'};\n";
   message += "Plotly.newPlot('TempHumPlot', data2, layout2);\n";
 
   message += "</script>\n</body>\n</html>\n";
@@ -322,8 +322,13 @@ void loadCredentials() {
 #endif /* MQTT */
 
 float getTempOffset() {
-  if (useWiFi) return 12.2;
-  else return 4.4;
+  if (!BatteryMode) {
+    if (useWiFi) return 12.2;
+    return 4.4;
+  } else {
+    if (lowEnergyMode) return 0.0;
+    return 0.8;
+  }
 }
 
 void initOnce() {
@@ -358,6 +363,7 @@ void initOnce() {
   preferences.begin("co2-sensor", true);
   maxBatteryVoltage = preferences.getFloat("MBV", 3.95);
   useWiFi = preferences.getBool("WiFi", false);
+  lowEnergyMode = preferences.getBool("lowEnergy", false);
   LEDonBattery = preferences.getBool("LEDonBattery", false);
   LEDonUSB = preferences.getBool("LEDonUSB", true);
   ledbrightness = preferences.getInt("ledbrightness", 5);
@@ -375,7 +381,7 @@ void initOnce() {
   scd4x.setSensorAltitude(HEIGHT_ABOVE_SEA_LEVEL);
   scd4x.setAutomaticSelfCalibrationEnabled(1); // Or use setAutomaticSelfCalibrationTarget if needed
   scd4x.setTemperatureOffset(getTempOffset());
-  scd4x.startPeriodicMeasurement();
+  if (!(BatteryMode && lowEnergyMode)) scd4x.startPeriodicMeasurement();
 
   displayInit();
   delay(3000);  // Wait for co2 measurement
@@ -820,29 +826,56 @@ void loop() {
     goto_light_sleep(5000 - (millis() - lastMeasurementTimeMs));
   }
 
-  bool isDataReady = false;
-  uint16_t ready_error = scd4x.getDataReadyStatus(isDataReady);
-  if (ready_error || !isDataReady) {
-    if (BatteryMode && comingFromDeepSleep) goto_deep_sleep(DEEP_SLEEP_TIME/2);
-    else goto_light_sleep(LIGHT_SLEEP_TIME/2);
-    return;  // otherwise continues running!
+  if (!(BatteryMode && lowEnergyMode)) {
+    bool isDataReady = false;
+    uint16_t ready_error = scd4x.getDataReadyStatus(isDataReady);
+    if (ready_error || !isDataReady) {
+      if (BatteryMode && comingFromDeepSleep) goto_deep_sleep(DEEP_SLEEP_TIME/2);
+      else goto_light_sleep(LIGHT_SLEEP_TIME/2);
+      return;  // otherwise continues running!
+    }
   }
 
   // Read co2 measurement
-  uint16_t new_co2 = 400;
+  uint16_t new_co2 = 420;
   float new_temperature = 0.0f;
-  uint16_t error = scd4x.readMeasurement(new_co2, new_temperature, humidity);
+  uint16_t error;
+  if (BatteryMode && lowEnergyMode) {
+    scd4x.stopPeriodicMeasurement();
+    scd4x.wakeUp();
+    scd4x.setTemperatureOffset(getTempOffset());
+    //delay(10);
+    scd4x.measureSingleShot(); // Ignore first measurement after wake up.
+    error = scd4x.measureAndReadSingleShot(new_co2, new_temperature, humidity);
+    scd4x.powerDown();
+  } else {
+    error = scd4x.readMeasurement(new_co2, new_temperature, humidity);
+  }
   lastMeasurementTimeMs = millis();
   if (error) {
-    char errorMessage[256];
-    errorToString(error, errorMessage, 256);
-    displayWriteError(errorMessage);
+    if(TEST_MODE) {
+      char errorMessage[256];
+      errorToString(error, errorMessage, 256);
+      displayWriteError(errorMessage);
+    } else { // retry
+      goto_light_sleep(LIGHT_SLEEP_TIME/2);
+      return;
+    }
   } else {
     extern uint16_t refreshes;
-    if (BatteryMode || (refreshes % 6 == 1)) saveMeasurement(new_co2, new_temperature, humidity);
-    /* don't update in Battery mode, unless CO2 has changed by 3% or temperature by 0.5°C */
+    if (BatteryMode || (refreshes % 6 == 1)) {
+      saveMeasurement(new_co2, new_temperature, humidity);
+
+      if (BatteryMode && lowEnergyMode) { // fill measurements of past 5 min
+        for (int i=0; i<9; i++) {
+          saveMeasurement(new_co2, new_temperature, humidity);
+        }
+      }
+    }
+
+    /* don't update in Battery mode, unless CO2 has changed by 4% or temperature by 0.5°C */
     if (!TEST_MODE && BatteryMode && comingFromDeepSleep) {
-      if ((abs(new_co2 - co2) < (0.03 * co2)) && (fabs(new_temperature - temperature) < 0.5)) {
+      if ((abs(new_co2 - co2) < (0.04 * co2)) && (fabs(new_temperature - temperature) < 0.5)) {
         goto_deep_sleep(DEEP_SLEEP_TIME_NO_DISPLAY_UPDATE);
       }
     }
@@ -893,10 +926,11 @@ void loop() {
   if (BatteryMode) {
     if (!comingFromDeepSleep) {
       scd4x.stopPeriodicMeasurement();
-      scd4x.setTemperatureOffset(0.8);
-      scd4x.startLowPowerPeriodicMeasurement();
+      scd4x.setTemperatureOffset(getTempOffset());
+      if (!lowEnergyMode) scd4x.startLowPowerPeriodicMeasurement();
     }
-    goto_deep_sleep(DEEP_SLEEP_TIME);
+    if (lowEnergyMode) goto_deep_sleep(LOW_ENERGY_DEEP_SLEEP_TIME);
+    else               goto_deep_sleep(DEEP_SLEEP_TIME);
   }
 
   goto_light_sleep(LIGHT_SLEEP_TIME);

epd_abstraction.h

@@ -22,6 +22,7 @@ enum LEDMenuOptions {
   NUM_LED_OPTIONS
 };
 enum DisplayMenuOptions {
+  UPDATE,
   INVERT,
   TEMP_UNIT,
   LANGUAGE,
@@ -55,6 +56,7 @@ const char* EnglishLEDmenuItems[NUM_LED_OPTIONS] = {
   "Exit"
 };
 const char* EnglishOptionsMenuItems[NUM_DISPLAY_OPTIONS] = {
+  "Update",
   "Invert",
   "Unit",
   "English",
@@ -86,6 +88,7 @@ const char* GermanLEDmenuItems[NUM_LED_OPTIONS] = {
   "Beenden"
 };
 const char* GermanOptionsMenuItems[NUM_DISPLAY_OPTIONS] = {
+  "Update",
   "Invert",
   "Einheit",
   "German",

epd_abstraction.ino

@@ -210,6 +210,18 @@ void OptionsMenu() {
       }
       if (mspressed > 1000) { // long press
         switch (selectedOption) {
+          case UPDATE:
+            lowEnergyMode = !lowEnergyMode;
+            preferences.begin("co2-sensor", false);
+            preferences.putBool("lowEnergy", lowEnergyMode);
+            preferences.end();
+
+            if (BatteryMode) {
+              scd4x.stopPeriodicMeasurement();
+              scd4x.setTemperatureOffset(getTempOffset());
+              if (!lowEnergyMode) scd4x.startPeriodicMeasurement();
+            }
+            break;
           case INVERT:
             invertDisplay = !invertDisplay;
             preferences.begin("co2-sensor", false);
@@ -790,9 +802,11 @@ void displayOptionsMenu(uint8_t selectedOption) {
     else         OptionsMenuItem = GermanOptionsMenuItems[i];
     Paint_DrawString_EN(5, 25*(i+1), OptionsMenuItem, &Font24, WHITE, BLACK);
   }
-  Paint_DrawString_EN(166, 50, (useFahrenheit? "*F":"*C"), &Font24, WHITE, BLACK);
-  Paint_DrawNum(149, 100, (int32_t)(font+1), &Font24, BLACK, WHITE);
-  Paint_DrawString_EN(166, 100, "/2", &Font24, WHITE, BLACK);
+  if (lowEnergyMode) Paint_DrawString_EN(200-17*4, 25, "5min", &Font24, WHITE, BLACK);
+  else Paint_DrawString_EN(200-17*5, 25, "30sec", &Font24, WHITE, BLACK);
+  Paint_DrawString_EN(166, 25*3, (useFahrenheit? "*F":"*C"), &Font24, WHITE, BLACK);
+  Paint_DrawNum(149, 25*5, (int32_t)(font+1), &Font24, BLACK, WHITE);
+  Paint_DrawString_EN(166, 25*5, "/2", &Font24, WHITE, BLACK);
 
   invertSelected(selectedOption);
   updateDisplay();
@@ -1225,12 +1239,13 @@ void displayinfo() {
   // only needed for debugging. This interrupts the SCD40
   /*float tOffset;
   scd4x.stopPeriodicMeasurement();
+  delay(10);
   scd4x.getTemperatureOffset(tOffset);
-  if (BatteryMode) scd4x.startLowPowerPeriodicMeasurement();
-  else scd4x.startPeriodicMeasurement();
+  if (!BatteryMode) scd4x.startPeriodicMeasurement();
+  else if (!lowEnergyMode) scd4x.startLowPowerPeriodicMeasurement();
   Paint_DrawString_EN(1, 145, "T_offset:", &Font16, WHITE, BLACK);
   char offset[20];
-  sprintf(offset, "%.1f", tOffset);
+  snprintf(offset, sizeof(offset), "%.2f", tOffset);
   Paint_DrawString_EN(122, 145, offset, &Font16, WHITE, BLACK);*/
 
   updateDisplay();
@@ -1311,6 +1326,15 @@ void displayBattery(uint8_t percentage) {
       BlackImage[y+x*25] = ~BlackImage[y+x*25];
     }
   }
+
+  /* low Energy Mode */
+  if (lowEnergyMode) {
+    Paint_DrawRectangle(97, 13, 115, 47, BLACK, DOT_PIXEL_2X2, DRAW_FILL_EMPTY); //case
+    Paint_DrawLine(103, 10, 109, 10, BLACK, DOT_PIXEL_3X3, LINE_STYLE_SOLID);//nippel
+    Paint_DrawLine(106, 25, 106, 35, BLACK, DOT_PIXEL_2X2, LINE_STYLE_SOLID);//+
+    Paint_DrawLine(102, 30, 110, 30, BLACK, DOT_PIXEL_2X2, LINE_STYLE_SOLID);//+
+    //Xstart, Ystart, Xend, Yend
+  }
 #endif /* EINK_1IN54V2 */
 
 #ifdef EINK_4IN2