Update voltage monitoring to use esp libraries

Author: bjpetit

tinyGS/src/ConfigManager/ConfigManager.cpp

@@ -53,7 +53,7 @@ ConfigManager::ConfigManager()
     : IotWebConf2(thingName, &dnsServer, &server, initialApPassword, configVersion), server(80), gsConfigHtmlFormatProvider(*this), boards({
   //OLED_add, OLED_SDA,  OLED_SCL, OLED_RST, PROG_BUTTON, BOARD_LED,      L_SX127X?,   L_NSS, L_DI00, L_DI01, L_BUSSY, L_RST,  L_MISO, L_MOSI, L_SCK, L_TCXO_V, RX_EN, TX_EN,     ADC_CTL, BAT_AIN, VBAT_SCALE,   BOARD
 #if CONFIG_IDF_TARGET_ESP32S3
-  {      0x3c,       17,        18,       21,           0,        35,      RADIO_SX1262,    8,   UNUSED,   14,      13,   12,      11,     10,     9,     1.6f,   UNUSED, UNUSED,     37,        1, 0.00405f, "150–960Mhz - HELTEC LORA32 V3 SX1262"    },  // SX1262
+  {      0x3c,       17,        18,       21,           0,        35,      RADIO_SX1262,    8,   UNUSED,   14,      13,   12,      11,     10,     9,     1.6f,   UNUSED, UNUSED,     37,        1, 5.1205f, "150–960Mhz - HELTEC LORA32 V3 SX1262"    },  // SX1262
   {      0x3c,       17,        18,     UNUSED,         0,        35,      RADIO_SX1278,    8,      6,     14,   UNUSED,  12,      11,     10,     9,     0.0f,   UNUSED, UNUSED, UNUSED,   UNUSED, UNUSED,   "Custom ESP32-S3 433MHz SX1278"     },  // SX1278 @g4lile0
   {      0x3c,       17,        18,     UNUSED,         0,         3,      RADIO_SX1262,   10,   UNUSED,    1,       4,    5,      13,     11,    12,     1.6f,   UNUSED, UNUSED, UNUSED,   UNUSED, UNUSED,   "433 Mhz TTGO T-Beam Sup SX1262 V1.0"    }, // SX1268 @ Stephen
   {      0x3c,       17,        18,     UNUSED,         0,        37,      RADIO_SX1280,    7,   UNUSED,    9,   UNUSED,   8,       3,      6,     5,     0.0f,       21,     10, UNUSED,   UNUSED, UNUSED,   "2.4Ghz LILYGO SX1280"    }, // SX1280 @ K4KDR
@@ -263,7 +263,11 @@ void ConfigManager::handleDashboard()
   s += "<tr><td>Radio </td><td>" + String(Radio::getInstance().isReady() ? "<span class='G'>READY</span>" : "<span class='R'>NOT READY</span>") + "</td></tr>";
   s += "<tr><td>Noise floor </td><td>" + String(status.modeminfo.currentRssi) + "</td></tr>";
   if (status.vbat > 0) {
-    s += "<tr><td>Battery </td><td>" + String(status.vbat) + "V " + String(getBatteryPercentage()) + "&percnt;</td></tr>";
+    if(getBatteryPercentage() > 100.0f) { // Charging
+      s += "<tr><td>Power </td><td>USB " + String(status.vbat) + "V</span></td></tr>";
+    } else {
+      s += "<tr><td>Power </td><td>Bat " + String(getBatteryPercentage(), 0) + "&percnt;" + String(status.vbat) + "V</span></td></tr>";
+    }
   } else {
     // Empty if battery monitoring not enabled
     s += "<tr><td></td><td></td></tr>";
@@ -505,7 +509,11 @@ void ConfigManager::handleRefreshWorldmap()
     radio.currentRssi ();
   data_string += String(status.modeminfo.currentRssi) + ",";
   if (status.vbat > 0) {
-    data_string += String(status.vbat) + "V " + String(getBatteryPercentage()) + "&percnt;,";
+    if(getBatteryPercentage() > 100.0f) { // Charging
+      data_string += "USB " + String(status.vbat) + "V,";
+    } else {
+      data_string += "Bat " + String(getBatteryPercentage(), 0) + "&percnt; " + String(status.vbat) + "V,";
+    }
   } else {
     //  if battery monitoring not enabled
     data_string += ",";

tinyGS/src/Display/Display.cpp

@@ -239,7 +239,11 @@ void drawFrame3(OLEDDisplay *display, OLEDDisplayUiState* state, int16_t x, int1
   if (status.vbat != 0.0)
   {
       display->setTextAlignment(TEXT_ALIGN_LEFT);
-      display->drawString(x, 45 + y, "Bat: " + String(status.vbat) + "V  " + (getBatteryPercentage()) + "%");
+      if(getBatteryPercentage() > 100.0f) {
+        display->drawString(x, 45 + y, "Pow: USB " + String(status.vbat) + "V");
+      } else {
+        display->drawString(x, 45 + y, "Pow: Bat " + String(getBatteryPercentage(), 0) + "% " + String(status.vbat) + "V");
+      }
   }
 }
 

tinyGS/src/Power/Battery.cpp

@@ -1,9 +1,15 @@
 // Battery.cpp
 // Battery monitoring helpers for tinyGS
 
+#include <stdlib.h>
 #include "Battery.h"
 #include "../ConfigManager/ConfigManager.h"
 #include "../Logger/Logger.h"
+#include <esp_adc_cal.h>
+
+esp_adc_cal_characteristics_t adc_chars;
+#define DEFAULT_VREF 1100
+
 
 // Arduino Framework Battery Writeup
 // https://digitalconcepts.net.au/arduino/index.php?op=Battery
@@ -28,18 +34,20 @@ void initBatteryMonitoring(void)
             // Use 12-bit resolution and 11dB attenuation for ~0-3.6V range
             analogReadResolution(12);
             analogSetAttenuation(ADC_11db);
+            // Characterize ADC for voltage conversion
+            esp_adc_cal_characterize(ADC_UNIT_1, ADC_ATTEN_11db, ADC_WIDTH_BIT_12, DEFAULT_VREF, &adc_chars);
         }
         checkBattery(); // Initial read to seed status.vbat
     }
 }
 
 // Drive the ADC control pin to the enabled state (if present) and wait
-// briefly for voltages to stabilise before taking a reading.
+// briefly for voltages to stabilize before taking a reading.
 inline void enableADCReading(board_t board)
 {
     if (board.ADC_CTL != UNUSED) {
         digitalWrite(board.ADC_CTL, ADC_READ_ENABLE);
-        delay(50); // Allow voltage to stabilise before sampling
+        delay(50); // Allow voltage to stabilize before sampling
     }
 }
 
@@ -69,13 +77,17 @@ void checkBattery(void)
 
         enableADCReading(board);
 
-        // Read raw ADC and convert using board-specific scale factor
-        uint16_t raw = analogRead(board.VBAT_AIN);
+        // Read raw ADC
+        int raw = adc1_get_raw(ADC1_CHANNEL_0);
 
         disableADCReading(board);
 
+        //Convert adc_reading to voltage in mV
+        uint32_t voltage = esp_adc_cal_raw_to_voltage(raw, &adc_chars);
+
         // Convert and smooth: seed or simple average with previous value
-        float measured = board.VBAT_SCALE * raw;
+        float measured = (board.VBAT_SCALE * voltage) / 1000.0f; // convert mV to V
+         Log::debug(PSTR("adc raw: %d, voltage: %f V"), raw, measured);
         if (status.vbat == 0.0) {
             status.vbat = measured; // initial seed
         } else {
@@ -87,13 +99,17 @@ void checkBattery(void)
 }
 
 // Convert the current battery voltage status.vbat to a percentage.
-// Assumes a linear discharge curve between 3.0V (0%) and 3.7V (100%).
+// Assumes a linear discharge curve between 3.0V (0%) and 4.15V (100%).
+// Returns 999.0f if the voltage is above 4.2V, indicating charging state.
 float getBatteryPercentage(void)
 {
-    const float maxVoltage = 3.7f; // Voltage at 100%
-    const float minVoltage = 3.0f; // Voltage at 0%
+    const float poweredVoltage = 4.23f; // Voltage above 100%
+    const float maxVoltage = 4.15f; // Voltage at 100%
+    const float minVoltage = 3.5f; // Voltage at 0%
     float voltage = status.vbat;
-    if (voltage >= maxVoltage) {
+    if (voltage >= poweredVoltage) {
+        return 999.0f; // Plugged in / charging
+    } else if (voltage >= maxVoltage) {
         return 100.0f;
     } else if (voltage <= minVoltage) {
         return 0.0f;