Add battery min/max voltage parameter support

examples/companion_radio/ui-new/UITask.cpp

@@ -103,8 +103,14 @@ class HomeScreen : public UIScreen {
 
   void renderBatteryIndicator(DisplayDriver& display, uint16_t batteryMilliVolts) {
     // Convert millivolts to percentage
-    const int minMilliVolts = 3000; // Minimum voltage (e.g., 3.0V)
-    const int maxMilliVolts = 4200; // Maximum voltage (e.g., 4.2V)
+#ifndef BATT_MIN_MILLIVOLTS
+  #define BATT_MIN_MILLIVOLTS 3000
+#endif
+#ifndef BATT_MAX_MILLIVOLTS
+  #define BATT_MAX_MILLIVOLTS 4200
+#endif
+    const int minMilliVolts = BATT_MIN_MILLIVOLTS;
+    const int maxMilliVolts = BATT_MAX_MILLIVOLTS;
     int batteryPercentage = ((batteryMilliVolts - minMilliVolts) * 100) / (maxMilliVolts - minMilliVolts);
     if (batteryPercentage < 0) batteryPercentage = 0; // Clamp to 0%
     if (batteryPercentage > 100) batteryPercentage = 100; // Clamp to 100%

examples/companion_radio/ui-orig/UITask.cpp

@@ -149,8 +149,14 @@ void UITask::newMsg(uint8_t path_len, const char* from_name, const char* text, i
 
 void UITask::renderBatteryIndicator(uint16_t batteryMilliVolts) {
   // Convert millivolts to percentage
-  const int minMilliVolts = 3000; // Minimum voltage (e.g., 3.0V)
-  const int maxMilliVolts = 4200; // Maximum voltage (e.g., 4.2V)
+#ifndef BATT_MIN_MILLIVOLTS
+  #define BATT_MIN_MILLIVOLTS 3000
+#endif
+#ifndef BATT_MAX_MILLIVOLTS
+  #define BATT_MAX_MILLIVOLTS 4200
+#endif
+  const int minMilliVolts = BATT_MIN_MILLIVOLTS;
+  const int maxMilliVolts = BATT_MAX_MILLIVOLTS;
   int batteryPercentage = ((batteryMilliVolts - minMilliVolts) * 100) / (maxMilliVolts - minMilliVolts);
   if (batteryPercentage < 0) batteryPercentage = 0; // Clamp to 0%
   if (batteryPercentage > 100) batteryPercentage = 100; // Clamp to 100%

variants/lilygo_tbeam_1w/platformio.ini

@@ -31,6 +31,10 @@ build_flags =
   ; TX power: 22dBm to SX1262, PA module adds ~10dB for 32dBm total
   -D LORA_TX_POWER=22
 
+  ; Battery - 2S 7.4V LiPo (6.0V min, 8.4V max)
+  -D BATT_MIN_MILLIVOLTS=6000
+  -D BATT_MAX_MILLIVOLTS=8400
+
   ; Display - SH1106 OLED at 0x3C
   -D DISPLAY_CLASS=SH1106Display