feat: battery voltage cutoff monitor

src/LoRa_APRS_iGate.cpp

@@ -18,7 +18,7 @@
 #include "display.h"
 #include "utils.h"
 #include <ElegantOTA.h>
-
+#include "battery_utils.h"
 
 Configuration   Config;
 WiFiClient      espClient;
@@ -42,6 +42,8 @@ bool            WiFiConnected         = false;
 bool            WiFiAutoAPStarted     = false;
 long            WiFiAutoAPTime        = false;
 
+uint32_t        lastBatteryCheck      = 0;
+
 uint32_t        bmeLastReading        = -60000;
 
 String          batteryVoltage;
@@ -56,7 +58,7 @@ String firstLine, secondLine, thirdLine, fourthLine, fifthLine, sixthLine, seven
 void setup() {
     Serial.begin(115200);
 
-    #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2)
+    #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2) || defined(HELTEC_WSL)
     pinMode(batteryPin, INPUT);
     #endif
     #ifdef HAS_INTERNAL_LED
@@ -94,6 +96,10 @@ void loop() {
         return; // Don't process IGate and Digi during OTA update
     }
 
+    if (BATTERY_Utils::checkIfShouldSleep()) {
+        ESP.deepSleep(1800000000); // 30 min sleep (60s = 60e6)
+    }
+
     thirdLine = Utils::getLocalIP();
 
     WIFI_Utils::checkWiFi(); // Always use WiFi, not related to IGate/Digi mode

src/battery_utils.cpp

@@ -2,7 +2,13 @@
 #include "configuration.h"
 #include "pins_config.h"
 
+// Uncomment if you want to monitor voltage and sleep if voltage is too low (<3.1V)
+#define LOW_VOLTAGE_CUTOFF
+
+float cutOffVoltage = 3.1;
+
 extern Configuration    Config;
+extern uint32_t         lastBatteryCheck;
 
 float adcReadingTransformation = (3.3/4095);
 float voltageDividerCorrection = 0.288;
@@ -16,11 +22,15 @@ float multiplyCorrection = 0.035;
 
 namespace BATTERY_Utils {
 
+    float mapVoltage(float voltage, float in_min, float in_max, float out_min, float out_max) {
+        return (voltage - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
+    }
+
     float checkBattery() { 
         int sample;
         int sampleSum = 0;
         for (int i=0; i<100; i++) {
-            #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2)
+            #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2) || defined(HELTEC_WSL)
             sample = analogRead(batteryPin);
             #endif
             #if defined(HELTEC_V3) || defined(ESP32_DIY_LoRa) || defined(ESP32_DIY_1W_LoRa)
@@ -29,7 +39,12 @@ namespace BATTERY_Utils {
             sampleSum += sample;
             delayMicroseconds(50); 
         }
-        return (2 * (sampleSum/100) * adcReadingTransformation) + voltageDividerCorrection;
+
+        float voltage = (2 * (sampleSum/100) * adcReadingTransformation) + voltageDividerCorrection;
+
+        return voltage; // raw voltage without mapping
+
+        // return mapVoltage(voltage, 3.34, 4.71, 3.0, 4.2); // mapped voltage
     }
 
     float checkExternalVoltage() {
@@ -40,7 +55,28 @@ namespace BATTERY_Utils {
             sampleSum += sample;
             delayMicroseconds(50); 
         }
-        return ((((sampleSum/100)* adcReadingTransformation) + readingCorrection) * ((R1+R2)/R2)) - multiplyCorrection;
+
+        float voltage = ((((sampleSum/100)* adcReadingTransformation) + readingCorrection) * ((R1+R2)/R2)) - multiplyCorrection;
+
+        return voltage; // raw voltage without mapping
+
+        // return mapVoltage(voltage, 5.05, 6.32, 4.5, 5.5); // mapped voltage
+    }
+
+    bool checkIfShouldSleep() {
+        #ifdef LOW_VOLTAGE_CUTOFF
+        if (lastBatteryCheck == 0 || millis() - lastBatteryCheck >= 15 * 60 * 1000) {
+            lastBatteryCheck = millis();
+
+            float voltage = checkBattery();
+            
+            if (voltage < cutOffVoltage) {
+                return true;
+            }
+        }
+        #endif
+
+        return false;
     }
 
 }

src/battery_utils.h

@@ -8,6 +8,7 @@ namespace BATTERY_Utils {
 
     float checkBattery();
     float checkExternalVoltage();
+    bool checkIfShouldSleep();
 
 }
 

src/pins_config.h

@@ -119,6 +119,9 @@
 #define HAS_INTERNAL_LED
 #endif
 
+#ifdef HELTEC_WSL
+#define batteryPin      1
+#endif
 #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2)
 #define internalLedPin  25      // Green Led
 #define batteryPin      35

src/utils.cpp

@@ -115,15 +115,17 @@ namespace Utils {
                 secondaryBeaconPacket = iGateLoRaBeaconPacket + Config.beacon.comment;
             }
 
-            #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2)
+            #if defined(TTGO_T_LORA32_V2_1) || defined(HELTEC_V2) || defined(HELTEC_WSL)
             if (Config.sendBatteryVoltage) {
-                beaconPacket += " (Batt=" + String(BATTERY_Utils::checkBattery(),2) + "V)";
+                beaconPacket += " Batt=" + String(BATTERY_Utils::checkBattery(),2) + "V";
+                secondaryBeaconPacket += " Batt=" + String(BATTERY_Utils::checkBattery(),2) + "V";
                 sixthLine = "     (Batt=" + String(BATTERY_Utils::checkBattery(),2) + "V)";
             }
             #endif
 
             if (Config.externalVoltageMeasurement) { 
-                beaconPacket += " (Ext V=" + String(BATTERY_Utils::checkExternalVoltage(),2) + "V)";
+                beaconPacket += " Ext=" + String(BATTERY_Utils::checkExternalVoltage(),2) + "V";
+                secondaryBeaconPacket += " Ext=" + String(BATTERY_Utils::checkExternalVoltage(),2) + "V";
                 sixthLine = "    (Ext V=" + String(BATTERY_Utils::checkExternalVoltage(),2) + "V)";
             }
 

src/web_utils.cpp

@@ -168,7 +168,6 @@ namespace WEB_Utils {
         String type = request->getParam("type", false)->value();
 
         if (type == "send-beacon") {
-            Serial.println(lastBeaconTx);
             lastBeaconTx = 0;
 
             request->send(200, "text/plain", "Beacon will be sent in a while");