Battery percentage display

include/globals.h

@@ -123,8 +123,8 @@ extern std::array<uint64_t, 0xff> beacons;
 extern configData_t cfg;                       // current device configuration
 extern char lmic_event_msg[LMIC_EVENTMSG_LEN]; // display buffer
 extern uint8_t volatile channel;               // wifi channel rotation counter
-extern uint16_t volatile macs_total, macs_wifi, macs_ble,
-    batt_voltage;                   // display values
+extern uint8_t batt_level;                     // display value
+extern uint16_t volatile macs_total, macs_wifi, macs_ble; // display values
 extern bool volatile TimePulseTick; // 1sec pps flag set by GPS or RTC
 extern timesource_t timeSource;
 extern hw_timer_t *displayIRQ, *matrixDisplayIRQ, *ppsIRQ;

include/power.h

@@ -12,10 +12,14 @@
 #define NO_OF_SAMPLES 64  // we do some multisampling to get better values
 
 #ifndef BAT_MAX_VOLTAGE
-#define BAT_MAX_VOLTAGE 4100 // millivolts
+#define BAT_MAX_VOLTAGE 4200 // millivolts
+#endif
+#ifndef BAT_MIN_VOLTAGE
+#define BAT_MIN_VOLTAGE 3100 // millivolts
 #endif
 
 uint16_t read_voltage(void);
+uint8_t read_battlevel(void);
 void calibrate_voltage(void);
 bool batt_sufficient(void);
 

src/cyclic.cpp

@@ -28,7 +28,7 @@ void doHousekeeping() {
     if (batt_sufficient()) {
       do_reset(true); // warmstart to runmode update
     } else {
-      ESP_LOGE(TAG, "Battery voltage %dmV too low for OTA", batt_voltage);
+      ESP_LOGE(TAG, "Battery level %d%% is too low for OTA", batt_level);
       RTC_runmode = RUNMODE_NORMAL; // keep running in normal mode
     }
   }
@@ -66,11 +66,11 @@ void doHousekeeping() {
 
 // read battery voltage into global variable
 #if (defined BAT_MEASURE_ADC || defined HAS_PMU)
-  batt_voltage = read_voltage();
-  if (batt_voltage == 0xffff)
+  batt_level = read_battlevel();
+  if (batt_level == MCMD_DEVS_EXT_POWER)
     ESP_LOGI(TAG, "Battery: external power");
   else
-    ESP_LOGI(TAG, "Battery: %dmV", batt_voltage);
+    ESP_LOGI(TAG, "Battery: %d%%", batt_level);
 #ifdef HAS_PMU
   AXP192_showstatus();
 #endif

src/display.cpp

@@ -281,12 +281,12 @@ void dp_drawPage(time_t t, bool nextpage) {
     // line 4: Battery + GPS status + Wifi channel
     // B:a.bcV Sats:ab ch:ab
 #if (defined BAT_MEASURE_ADC || defined HAS_PMU)
-    if (batt_voltage == 0xffff)
+    if (batt_level == MCMD_DEVS_EXT_POWER)
       dp_printf("USB     ");
-    else if (batt_voltage == 0)
+    else if (batt_level == MCMD_DEVS_BATT_NOINFO)
       dp_printf("No batt ");
     else
-      dp_printf("B:%.2fV ", batt_voltage / 1000.0);
+      dp_printf("B:%3d%%  ", batt_level);
 #else
     dp_printf("       ");
 #endif

src/main.cpp

@@ -79,8 +79,9 @@ triggers pps 1 sec impulse
 configData_t cfg; // struct holds current device configuration
 char lmic_event_msg[LMIC_EVENTMSG_LEN]; // display buffer for LMIC event message
 uint8_t volatile channel = 0;           // channel rotation counter
-uint16_t volatile macs_total = 0, macs_wifi = 0, macs_ble = 0,
-                  batt_voltage = 0; // globals for display
+uint8_t batt_level = 0;                 // display value
+uint16_t volatile macs_total = 0, macs_wifi = 0,
+                  macs_ble = 0; // globals for display
 
 hw_timer_t *ppsIRQ = NULL, *displayIRQ = NULL, *matrixDisplayIRQ = NULL;
 
@@ -260,7 +261,7 @@ void setup() {
 #if (defined BAT_MEASURE_ADC || defined HAS_PMU)
   strcat_P(features, " BATT");
   calibrate_voltage();
-  batt_voltage = read_voltage();
+  batt_level = read_battlevel();
 #endif
 
 #if (USE_OTA)

src/power.cpp

@@ -63,7 +63,7 @@ void AXP192_powerevent_IRQ(void) {
   pmu.clearIRQ();
 
   // refresh stored voltage value
-  read_voltage();
+  read_battlevel();
 }
 
 void AXP192_power(pmu_power_t powerlevel) {
@@ -175,21 +175,11 @@ void calibrate_voltage(void) {
 #endif
 }
 
-bool batt_sufficient() {
-#if (defined HAS_PMU || defined BAT_MEASURE_ADC)
-  uint16_t volts = read_voltage();
-  return ((volts < 1000) ||
-          (volts > OTA_MIN_BATT)); // no battery or battery sufficient
-#else
-  return true;
-#endif
-}
-
-uint16_t read_voltage() {
+uint16_t read_voltage(void) {
   uint16_t voltage = 0;
 
 #ifdef HAS_PMU
-  voltage = pmu.isVBUSPlug() ? 0xffff : pmu.getBattVoltage();
+  voltage = pmu.getBattVoltage();
 #else
 
 #ifdef BAT_MEASURE_ADC
@@ -217,28 +207,56 @@ uint16_t read_voltage() {
 
 #endif // HAS_PMU
 
-  /*
-  // set battery level value for lmic stack
-  #if (HAS_LORA)
-    // Sets the battery level returned in MAC Command DevStatusAns.
-    // Available defines in lorabase.h:
+  return voltage;
+}
+
+uint8_t read_battlevel() {
+
+  // return the battery value as sent in MAC Command
+  // DevStatusAns. Available defines in lorabase.h:
   //   MCMD_DEVS_EXT_POWER   = 0x00, // external power supply
   //   MCMD_DEVS_BATT_MIN    = 0x01, // min battery value
   //   MCMD_DEVS_BATT_MAX    = 0xFE, // max battery value
   //   MCMD_DEVS_BATT_NOINFO = 0xFF, // unknown battery level
-    // When setting the battery level calculate the applicable
-    // value from MCMD_DEVS_BATT_MIN to MCMD_DEVS_BATT_MAX.
+  // we calculate the applicable value from MCMD_DEVS_BATT_MIN to
+  // MCMD_DEVS_BATT_MAX from bat_percent value
 
-    // external power
-    if (voltage == 0xffff)
-      LMIC_setBattLevel(MCMD_DEVS_EXT_POWER);
-    // scale battery millivolts to lmic battlevel
+  const uint16_t batt_voltage_range = BAT_MAX_VOLTAGE - BAT_MIN_VOLTAGE;
+  const uint8_t batt_level_range = MCMD_DEVS_BATT_MAX - MCMD_DEVS_BATT_MIN + 1;
+  const uint16_t batt_voltage = read_voltage() - BAT_MIN_VOLTAGE;
+  const uint8_t batt_percent =
+      batt_voltage > 0 ? batt_voltage / batt_voltage_range * 100 : 0;
+  uint8_t lmic_batt_level;
+
+#ifdef HAS_PMU
+  if (batt_percent > 0)
+    lmic_batt_level = pmu.isVBUSPlug() ? MCMD_DEVS_EXT_POWER
+                                       : batt_percent / 100 * batt_level_range;
   else
-      LMIC_setBattLevel(voltage / BAT_MAX_VOLTAGE *
-                        (MCMD_DEVS_BATT_MAX - MCMD_DEVS_BATT_MIN + 1));
+    lmic_batt_level = MCMD_DEVS_BATT_NOINFO;
+#else
+  if (batt_percent > 0)
+    lmic_batt_level = batt_percent / 100 * batt_level_range;
+  else
+    lmic_batt_level = MCMD_DEVS_BATT_NOINFO;
+#endif // HAS_PMU
 
-#endif // (HAS_LORA)
-*/
+// set battery level value for lmic stack
+#if (HAS_LORA)
+  //LMIC_setBattLevel(lmic_batt_level);
+#endif
 
-  return voltage;
+  return batt_percent;
+}
+
+bool batt_sufficient() {
+#if (defined HAS_PMU || defined BAT_MEASURE_ADC)
+  uint8_t my_batt_level = read_battlevel();
+  if (my_batt_level == MCMD_DEVS_EXT_POWER)
+    return true;
+  else
+    return (my_batt_level > OTA_MIN_BATT);
+#else
+  return true; // we don't know batt level
+#endif
 }