battery percentage calculation improved

src/cyclic.cpp

@@ -68,10 +68,6 @@ void doHousekeeping() {
 #if (defined BAT_MEASURE_ADC || defined HAS_PMU)
   batt_level = read_battlevel();
   ESP_LOGI(TAG, "Battery: %d%%", batt_level);
-#if (HAS_LORA)
-  // to come with future LMIC version
-  // lora_setBattLevel(batt_level);
-#endif
 #ifdef HAS_PMU
   AXP192_showstatus();
 #endif

src/lorawan.cpp

@@ -485,12 +485,10 @@ void lora_setBattLevel(uint8_t batt_percent) {
 #endif // HAS_PMU
 
   else
-    lmic_batt_level = static_cast<uint8_t>(
-        (float)batt_percent /
-        (float)(MCMD_DEVS_BATT_MAX - MCMD_DEVS_BATT_MIN + 1) * 100.0f);
+    lmic_batt_level =
+        batt_percent / 100.0 * (MCMD_DEVS_BATT_MAX - MCMD_DEVS_BATT_MIN + 1);
 
   LMIC_setBattLevel(lmic_batt_level);
-  ESP_LOGD(TAG, "lmic_batt_level = %d", lmic_batt_level);
 }
 
 // event EV_RXCOMPLETE message handler

src/power.cpp

@@ -210,19 +210,29 @@ uint16_t read_voltage(void) {
   return voltage;
 }
 
-uint8_t read_battlevel() {
+uint8_t read_battlevel(mapFn_t mapFunction) {
 
-  // return the battery level in values 0 ... 255 [percent],
-  // values > 100 probably mean external power, depending on hardware
+  // returns the estimated battery level in values 0 ... 100 [percent],
 
   const uint16_t batt_voltage = read_voltage();
-  float batt_percent_fl = (float)(batt_voltage - BAT_MIN_VOLTAGE) /
-                          (float)(BAT_MAX_VOLTAGE - BAT_MIN_VOLTAGE) * 100.0f;
-  const uint8_t batt_percent = static_cast<uint8_t>(batt_percent_fl);
+  uint8_t batt_percent;
 
-  ESP_LOGD(TAG, "batt_voltage = %dmV / batt_percent = %u%%", batt_voltage,
+  if (batt_voltage <= BAT_MIN_VOLTAGE)
+    batt_percent = 0;
+  else if (batt_voltage >= BAT_MAX_VOLTAGE)
+    batt_percent = 100;
+  else
+    batt_percent =
+        (*mapFunction)(batt_voltage, BAT_MIN_VOLTAGE, BAT_MAX_VOLTAGE);
+
+  ESP_LOGD(TAG, "batt_voltage = %dmV / batt_percent = %d%%", batt_voltage,
            batt_percent);
 
+#if (HAS_LORA)
+  // to come with future LMIC version
+  // lora_setBattLevel(batt_percent);
+#endif
+
   return batt_percent;
 }