Improved ESP32 battery voltage meter. Good both for Standalone and Pr…

…ime Mk2. Voltage readings are about 0.1V higher than actual value - but it Ok for now.

software/firmware/source/SoftRF/BatteryHelper.cpp

@@ -23,10 +23,10 @@
 
 void Battery_setup()
 {
-
+  SoC->Battery_setup();
 }
 
 float Battery_voltage()
 {
-  return analogRead (SOC_GPIO_PIN_BATTERY) / SOC_A0_VOLTAGE_DIVIDER ;
+  return SoC->Battery_voltage();
 }

software/firmware/source/SoftRF/Platform_ESP32.cpp

@@ -33,6 +33,7 @@
 #include "LEDHelper.h"
 #include "GNSSHelper.h"
 
+#include <battery.h>
 #include <U8x8lib.h>
 
 // RFM95W pin mapping
@@ -82,9 +83,6 @@ static void ESP32_setup()
 
   ledcSetup(LEDC_CHANNEL_BUZZER, 0, LEDC_RESOLUTION_BUZZER);
 
-  analogReadResolution(10);
-  analogSetPinAttenuation(SOC_GPIO_PIN_BATTERY, ADC_11db);
-
   /* Pre-init 1st ESP32 I2C bus to stick on these pins */
   Wire.begin(SOC_GPIO_PIN_SDA, SOC_GPIO_PIN_SCL);
 
@@ -423,6 +421,20 @@ static void ESP32_OLED_loop()
   }
 }
 
+static void ESP32_Battery_setup()
+{
+  calibrate_voltage(esp32_board == ESP32_TTGO_T_BEAM ?
+                    ADC1_GPIO35_CHANNEL : ADC1_GPIO36_CHANNEL);
+}
+
+static float ESP32_Battery_voltage()
+{
+  float voltage = ((float) read_voltage()) * 0.001 ;
+
+  /* T-Beam has voltage divider 100k/100k on board */
+  return (esp32_board == ESP32_TTGO_T_BEAM ? 2 * voltage : voltage);
+}
+
 static void IRAM_ATTR ESP32_GNSS_PPS_Interrupt_handler() {
   portENTER_CRITICAL_ISR(&GNSS_PPS_mutex);
   PPS_TimeMarker = millis();    /* millis() has IRAM_ATTR */
@@ -461,6 +473,8 @@ SoC_ops_t ESP32_ops = {
   ESP32_swSer_enableRx,
   &ESP32_Bluetooth_ops,
   ESP32_OLED_loop,
+  ESP32_Battery_setup,
+  ESP32_Battery_voltage,
   ESP32_GNSS_PPS_Interrupt_handler,
   ESP32_get_PPS_TimeMarker
 };

software/firmware/source/SoftRF/Platform_ESP32.h

@@ -63,8 +63,6 @@ extern NeoPixelBus<NeoGrbFeature, Neo800KbpsMethod> strip;
 extern Adafruit_NeoPixel strip;
 #endif /* USE_NEOPIXELBUS_LIBRARY */
 
-#define SOC_A0_VOLTAGE_DIVIDER  (1023.0 / 3.5 /* 3.9 */)
-
 #define LEDC_CHANNEL_BUZZER     0
 #define LEDC_RESOLUTION_BUZZER  8
 
@@ -98,6 +96,8 @@ extern Adafruit_NeoPixel strip;
 /* TTGO T-BEAM GPS module */
 #define SOC_GPIO_PIN_TBEAM_RX 12
 #define SOC_GPIO_PIN_TBEAM_TX 15
+/* TTGO T-BEAM battery voltage */
+#define SOC_GPIO_PIN_TBEAM_BATTERY  35
 
 #define SSD1306_OLED_I2C_ADDR 0x3C
 

software/firmware/source/SoftRF/Platform_ESP8266.cpp

@@ -233,6 +233,16 @@ static void ESP8266_OLED_loop()
 
 }
 
+static void ESP8266_Battery_setup()
+{
+
+}
+
+static float ESP8266_Battery_voltage()
+{
+  return analogRead (SOC_GPIO_PIN_BATTERY) / SOC_A0_VOLTAGE_DIVIDER ;
+}
+
 void ESP8266_GNSS_PPS_Interrupt_handler() {
   PPS_TimeMarker = millis();
 }
@@ -265,6 +275,8 @@ SoC_ops_t ESP8266_ops = {
   ESP8266_swSer_enableRx,
   NULL, /* ESP8266 has no built-in Bluetooth */
   ESP8266_OLED_loop,
+  ESP8266_Battery_setup,
+  ESP8266_Battery_voltage,
   ESP8266_GNSS_PPS_Interrupt_handler,
   ESP8266_get_PPS_TimeMarker
 };

software/firmware/source/SoftRF/SoCHelper.h

@@ -50,6 +50,8 @@ typedef struct SoC_ops_struct {
   void (*swSer_enableRx)(boolean);
   Bluetooth_ops_t *Bluetooth;
   void (*OLED_loop)();
+  void (*Battery_setup)();
+  float (*Battery_voltage)();
   void (*GNSS_PPS_handler)();
   unsigned long (*get_PPS_TimeMarker)();
 } SoC_ops_t;

software/firmware/source/SoftRF/SoftRF.ino

@@ -100,7 +100,6 @@ void setup()
   Serial.println(SoC->getResetInfo()); Serial.println("");
 
   EEPROM_setup();
-  Battery_setup();
 
   ThisAircraft.addr = SoC->getChipId() & 0x00FFFFFF;
 
@@ -126,6 +125,7 @@ void setup()
   ThisAircraft.stealth  = settings->stealth;
   ThisAircraft.no_track = settings->no_track;
 
+  Battery_setup();
   Traffic_setup();
 
   SoC->swSer_enableRx(false);