low power improvements, display and bme now powered off GPIO pins

platformio/include/config.h

@@ -199,6 +199,12 @@
 //   Disable alerts by changing the DISPLAY_ALERTS macro to 0.
 #define DISPLAY_ALERTS 1
 
+// STATUS BAR EXTRAS
+//   Extra information that can be displayed on the status bar. Set to 1 to
+//   enable.
+#define STATUS_BAR_EXTRAS_BAT_VOLTAGE 0
+#define STATUS_BAR_EXTRAS_WIFI_RSSI   0
+
 // BATTERY MONITORING
 //   You may choose to power your whether display with or without a battery.
 //   Low power behavior can be controlled in config.cpp.
@@ -223,8 +229,10 @@ extern const uint8_t PIN_EPD_DC;
 extern const uint8_t PIN_EPD_SCK;
 extern const uint8_t PIN_EPD_MISO;
 extern const uint8_t PIN_EPD_MOSI;
+extern const uint8_t PIN_EPD_PWR;
 extern const uint8_t PIN_BME_SDA;
 extern const uint8_t PIN_BME_SCL;
+extern const uint8_t PIN_BME_PWR;
 extern const uint8_t BME_ADDRESS;
 extern const char *WIFI_SSID;
 extern const char *WIFI_PASSWORD;

platformio/include/display_utils.h

@@ -73,6 +73,7 @@ const uint8_t *getWindBitmap24(int windDeg);
 const char *getHttpResponsePhrase(int code);
 const char *getWifiStatusPhrase(wl_status_t status);
 void printHeapUsage();
+void disableBuiltinLED();
 
 #endif
 

platformio/include/renderer.h

@@ -69,6 +69,7 @@ void drawMultiLnString(int16_t x, int16_t y, const String &text,
                        uint16_t max_lines, int16_t line_spacing,
                        uint16_t color=GxEPD_BLACK);
 void initDisplay();
+void powerOffDisplay();
 void drawCurrentConditions(const owm_current_t &current,
                            const owm_daily_t &today,
                            const owm_resp_air_pollution_t &owm_air_pollution,

platformio/src/config.cpp

@@ -29,10 +29,12 @@ const uint8_t PIN_EPD_DC   = 22;
 const uint8_t PIN_EPD_SCK  = 18;
 const uint8_t PIN_EPD_MISO = 19; // 19 Master-In Slave-Out not used, as no data from display
 const uint8_t PIN_EPD_MOSI = 23;
+const uint8_t PIN_EPD_PWR  = 14; // Irrelevant if directly connected to 3.3V
 // I2C Pins used for BME280
-const uint8_t PIN_BME_SDA = 17;   // 27 for micro-usb firebeetle
-const uint8_t PIN_BME_SCL = 16;   // 26 for micro-usb firebeetle
-const uint8_t BME_ADDRESS = 0x76; // if sensor does not work, try 0x77
+const uint8_t PIN_BME_SDA = 17;
+const uint8_t PIN_BME_SCL = 16;
+const uint8_t PIN_BME_PWR =  4;   // Irrelevant if directly connected to 3.3V
+const uint8_t BME_ADDRESS = 0x76; // If sensor does not work, try 0x77
 
 // WIFI
 const char *WIFI_SSID     = "ssid";

platformio/src/display_utils.cpp

@@ -1667,3 +1667,15 @@ const char *getWifiStatusPhrase(wl_status_t status)
   default:  return "";
   }
 } // end getWifiStatusPhrase
+
+/* This function sets the builtin LED to LOW and disables it even during deep
+ * sleep.
+ */
+void disableBuiltinLED()
+{
+  pinMode(LED_BUILTIN, OUTPUT);
+  digitalWrite(LED_BUILTIN, LOW);
+  gpio_hold_en(static_cast<gpio_num_t>(LED_BUILTIN));
+  gpio_deep_sleep_hold_en();
+  return;
+} // end disableBuiltinLED

platformio/src/main.cpp

@@ -18,6 +18,7 @@
 #include <Arduino.h>
 #include <Adafruit_BME280.h>
 #include <Adafruit_Sensor.h>
+#include <driver/adc.h>
 #include <Preferences.h>
 #include <time.h>
 #include <WiFi.h>
@@ -127,15 +128,19 @@ void setup()
   printHeapUsage();
 #endif
 
+  disableBuiltinLED();
+
   // Open namespace for read/write to non-volatile storage
   prefs.begin(NVS_NAMESPACE, false);
 
 #if BATTERY_MONITORING
   // GET BATTERY VOLTAGE
   // DFRobot FireBeetle Esp32-E V1.0 has voltage divider (1M+1M), so readings
   // are multiplied by 2. Readings are divided by 1000 to convert mV to V.
-  double batteryVoltage =
-            static_cast<double>(analogRead(PIN_BAT_ADC)) / 1000.0 * (3.5 / 2.0);
+  adc_power_acquire();
+  uint16_t batADC = analogRead(PIN_BAT_ADC);
+  adc_power_release();
+  double batteryVoltage = static_cast<double>(batADC) / 1000.0 * (3.5 / 2.0);
             // use / 1000.0 * (3.3 / 2.0) multiplier above for firebeetle esp32
             // use / 1000.0 * (3.5 / 2.0) for firebeetle esp32-E
   Serial.println("Battery voltage: " + String(batteryVoltage, 2));
@@ -158,7 +163,7 @@ void setup()
       {
         drawError(battery_alert_0deg_196x196, "Low Battery", "");
       } while (display.nextPage());
-      display.powerOff();
+      powerOffDisplay();
     }
 
     if (batteryVoltage <= CRIT_LOW_BATTERY_VOLTAGE)
@@ -225,7 +230,7 @@ void setup()
         drawError(wifi_x_196x196, "WiFi Connection", "Failed");
       } while (display.nextPage());
     }
-    display.powerOff();
+    powerOffDisplay();
     beginDeepSleep(startTime, &timeInfo);
   }
 
@@ -241,7 +246,7 @@ void setup()
     {
       drawError(wi_time_4_196x196, "Time Synchronization", "Failed");
     } while (display.nextPage());
-    display.powerOff();
+    powerOffDisplay();
     beginDeepSleep(startTime, &timeInfo);
   }
 
@@ -266,7 +271,7 @@ void setup()
     {
       drawError(wi_cloud_down_196x196, statusStr, tmpStr);
     } while (display.nextPage());
-    display.powerOff();
+    powerOffDisplay();
     beginDeepSleep(startTime, &timeInfo);
   }
   rxStatus = getOWMairpollution(client, owm_air_pollution);
@@ -280,12 +285,14 @@ void setup()
     {
       drawError(wi_cloud_down_196x196, statusStr, tmpStr);
     } while (display.nextPage());
-    display.powerOff();
+    powerOffDisplay();
     beginDeepSleep(startTime, &timeInfo);
   }
   killWiFi(); // WiFi no longer needed
 
   // GET INDOOR TEMPERATURE AND HUMIDITY, start BME280...
+  pinMode(PIN_BME_PWR, OUTPUT);
+  digitalWrite(PIN_BME_PWR, HIGH);
   float inTemp     = NAN;
   float inHumidity = NAN;
   Serial.print("Reading from BME280... ");
@@ -317,6 +324,7 @@ void setup()
     statusStr = "BME not found"; // check wiring
     Serial.println(statusStr);
   }
+  digitalWrite(PIN_BME_PWR, LOW);
 
   String refreshTimeStr;
   getRefreshTimeStr(refreshTimeStr, timeConfigured, &timeInfo);
@@ -337,7 +345,7 @@ void setup()
 #endif
     drawStatusBar(statusStr, refreshTimeStr, wifiRSSI, batteryVoltage);
   } while (display.nextPage());
-  display.powerOff();
+  powerOffDisplay();
 
   // DEEP-SLEEP
   beginDeepSleep(startTime, &timeInfo);

platformio/src/renderer.cpp

@@ -224,6 +224,8 @@ void drawMultiLnString(int16_t x, int16_t y, const String &text,
  */
 void initDisplay()
 {
+  pinMode(PIN_EPD_PWR, OUTPUT);
+  digitalWrite(PIN_EPD_PWR, HIGH);
   display.init(115200, true, 2, false);
   SPI.begin(PIN_EPD_SCK,
             PIN_EPD_MISO,
@@ -237,6 +239,16 @@ void initDisplay()
   // display.fillScreen(GxEPD_WHITE);
   display.setFullWindow();
   display.firstPage(); // use paged drawing mode, sets fillScreen(GxEPD_WHITE)
+  return;
+} // end initDisplay
+
+/* Power-off e-paper display
+ */
+void powerOffDisplay()
+{
+  display.powerOff();
+  digitalWrite(PIN_EPD_PWR, LOW);
+  return;
 } // end initDisplay
 
 /* This function is responsible for drawing the current conditions and
@@ -1085,8 +1097,10 @@ void drawStatusBar(const String &statusStr, const String &refreshTimeStr,
   if (batVoltage < BATTERY_WARN_VOLTAGE) {
     dataColor = ACCENT_COLOR;
   }
-  dataStr = String(batPercent) + "% ("
-            + String( round(100.0 * batVoltage) / 100.0, 2 ) + "v)";
+  dataStr = String(batPercent) + "%";
+#if STATUS_BAR_EXTRAS_BAT_VOLTAGE
+  dataStr += " (" + String( round(100.0 * batVoltage) / 100.0, 2 ) + "v)";
+#endif
   drawString(pos, DISP_HEIGHT - 1 - 2, dataStr, RIGHT, dataColor);
   pos -= getStringWidth(dataStr) + 25;
   display.drawInvertedBitmap(pos, DISP_HEIGHT - 1 - 17,
@@ -1097,10 +1111,12 @@ void drawStatusBar(const String &statusStr, const String &refreshTimeStr,
   // WiFi
   dataStr = String(getWiFidesc(rssi));
   dataColor = rssi >= -70 ? GxEPD_BLACK : ACCENT_COLOR;
+#if STATUS_BAR_EXTRAS_WIFI_RSSI
   if (rssi != 0)
   {
     dataStr += " (" + String(rssi) + "dBm)";
   }
+#endif
   drawString(pos, DISP_HEIGHT - 1 - 2, dataStr, RIGHT, dataColor);
   pos -= getStringWidth(dataStr) + 19;
   display.drawInvertedBitmap(pos, DISP_HEIGHT - 1 - 13, getWiFiBitmap16(rssi),