Notify battery level every 10 minutes when connected to a BLE host.

Refactor battery percent : only use uint8_t to store the battery % remaining.

src/components/battery/BatteryController.cpp

@@ -1,9 +1,7 @@
 #include "BatteryController.h"
 #include <hal/nrf_gpio.h>
 #include <nrfx_saadc.h>
-#include <libraries/log/nrf_log.h>
 #include <algorithm>
-#include <math.h>
 
 using namespace Pinetime::Controllers;
 
@@ -18,7 +16,6 @@ void Battery::Init() {
 }
 
 void Battery::Update() {
-
   isCharging = !nrf_gpio_pin_read(chargingPin);
   isPowerPresent = !nrf_gpio_pin_read(powerPresentPin);
 
@@ -33,13 +30,13 @@ void Battery::Update() {
   nrfx_saadc_sample();
 }
 
-void Battery::adcCallbackStatic(nrfx_saadc_evt_t const* event) {
+void Battery::AdcCallbackStatic(nrfx_saadc_evt_t const* event) {
   instance->SaadcEventHandler(event);
 }
 
 void Battery::SaadcInit() {
   nrfx_saadc_config_t adcConfig = NRFX_SAADC_DEFAULT_CONFIG;
-  APP_ERROR_CHECK(nrfx_saadc_init(&adcConfig, adcCallbackStatic));
+  APP_ERROR_CHECK(nrfx_saadc_init(&adcConfig, AdcCallbackStatic));
 
   nrf_saadc_channel_config_t adcChannelConfig = {.resistor_p = NRF_SAADC_RESISTOR_DISABLED,
                                                  .resistor_n = NRF_SAADC_RESISTOR_DISABLED,
@@ -55,7 +52,6 @@ void Battery::SaadcInit() {
 }
 
 void Battery::SaadcEventHandler(nrfx_saadc_evt_t const* p_event) {
-
   const uint16_t battery_max = 4180; // maximum voltage of battery ( max charging voltage is 4.21 )
   const uint16_t battery_min = 3200; // minimum voltage of battery before shutdown ( depends on the battery )
 
@@ -69,13 +65,10 @@ void Battery::SaadcEventHandler(nrfx_saadc_evt_t const* p_event) {
     // reference_voltage is 0.6V
     // p_event->data.done.p_buffer[0] = (adc_voltage / reference_voltage) * 1024
     voltage = p_event->data.done.p_buffer[0] * 6000 / 1024;
-
     percentRemaining = (voltage - battery_min) * 100 / (battery_max - battery_min);
-
     percentRemaining = std::max(percentRemaining, 0);
     percentRemaining = std::min(percentRemaining, 100);
-
+    percentRemainingBuffer.Insert(percentRemaining);
-    percentRemainingBuffer.insert(percentRemaining);
 
     samples++;
     if (samples > percentRemainingSamples) {

src/components/battery/BatteryController.h

@@ -19,7 +19,7 @@ namespace Pinetime {
      insert member function overwrites the next data to the current
     HEAD and moves the HEAD to the newly inserted value.
     */
-      void insert(const int num) {
+      void Insert(const uint8_t num) {
         head %= cap;
         arr[head++] = num;
         if (sz != cap) {
@@ -27,13 +27,13 @@ namespace Pinetime {
         }
       }
 
-      int GetAverage() const {
+      uint8_t GetAverage() const {
         int sum = std::accumulate(arr.begin(), arr.end(), 0);
-        return (sum / sz);
+        return static_cast<uint8_t>(sum / sz);
       }
 
     private:
-      std::array<int, N> arr; /**< internal array used to store the values*/
+      std::array<uint8_t, N> arr; /**< internal array used to store the values*/
       uint8_t sz;             /**< The current size of the array.*/
       uint8_t cap;            /**< Total capacity of the CircBuffer.*/
       uint8_t head;           /**< The current head of the CircBuffer*/
@@ -46,8 +46,11 @@ namespace Pinetime {
       void Init();
       void Update();
 
-      int PercentRemaining() const {
+      uint8_t PercentRemaining() const {
-        return percentRemainingBuffer.GetAverage();
+        auto avg = percentRemainingBuffer.GetAverage();
+        avg = std::min(avg, static_cast<uint8_t>(100));
+        avg = std::max(avg, static_cast<uint8_t>(0));
+        return avg;
       }
 
       uint16_t Voltage() const {
@@ -57,6 +60,7 @@ namespace Pinetime {
       bool IsCharging() const {
         return isCharging;
       }
+
       bool IsPowerPresent() const {
         return isPowerPresent;
       }
@@ -80,7 +84,7 @@ namespace Pinetime {
       void SaadcInit();
 
       void SaadcEventHandler(nrfx_saadc_evt_t const* p_event);
-      static void adcCallbackStatic(nrfx_saadc_evt_t const* event);
+      static void AdcCallbackStatic(nrfx_saadc_evt_t const* event);
 
       bool isReading = false;
       uint8_t samples = 0;

src/components/ble/BatteryInformationService.cpp

@@ -17,7 +17,7 @@ BatteryInformationService::BatteryInformationService(Controllers::Battery& batte
     characteristicDefinition {{.uuid = (ble_uuid_t*) &batteryLevelUuid,
                                .access_cb = BatteryInformationServiceCallback,
                                .arg = this,
-                               .flags = BLE_GATT_CHR_F_READ,
+                               .flags = BLE_GATT_CHR_F_READ | BLE_GATT_CHR_F_NOTIFY,
                                .val_handle = &batteryLevelHandle},
                               {0}},
     serviceDefinition {
@@ -49,3 +49,7 @@ int BatteryInformationService::OnBatteryServiceRequested(uint16_t connectionHand
   }
   return 0;
 }
+void BatteryInformationService::NotifyBatteryLevel(uint16_t connectionHandle, uint8_t level) {
+  auto* om = ble_hs_mbuf_from_flat(&level, 1);
+  ble_gattc_notify_custom(connectionHandle, batteryLevelHandle, om);
+}

src/components/ble/BatteryInformationService.h

@@ -17,7 +17,7 @@ namespace Pinetime {
       void Init();
 
       int OnBatteryServiceRequested(uint16_t connectionHandle, uint16_t attributeHandle, ble_gatt_access_ctxt* context);
-
+      void NotifyBatteryLevel(uint16_t connectionHandle, uint8_t level);
     private:
       Controllers::Battery& batteryController;
       static constexpr uint16_t batteryInformationServiceId {0x180F};

src/components/ble/NimbleController.cpp

@@ -235,3 +235,9 @@ void NimbleController::StartDiscovery() {
 uint16_t NimbleController::connHandle() {
   return connectionHandle;
 }
+
+void NimbleController::NotifyBatteryLevel(uint8_t level) {
+  if(connectionHandle != BLE_HS_CONN_HANDLE_NONE) {
+    batteryInformationService.NotifyBatteryLevel(connectionHandle, level);
+  }
+}

src/components/ble/NimbleController.h

@@ -70,6 +70,7 @@ namespace Pinetime {
       };
 
       uint16_t connHandle();
+      void NotifyBatteryLevel(uint8_t level);
 
     private:
       static constexpr const char* deviceName = "InfiniTime";
@@ -92,7 +93,7 @@ namespace Pinetime {
       HeartRateService heartRateService;
 
       uint8_t addrType; // 1 = Random, 0 = PUBLIC
-      uint16_t connectionHandle = 0;
+      uint16_t connectionHandle = BLE_HS_CONN_HANDLE_NONE;
 
       ble_uuid128_t dfuServiceUuid {
         .u {.type = BLE_UUID_TYPE_128},

src/displayapp/screens/BatteryIcon.cpp

@@ -1,9 +1,10 @@
+#include <cstdint>
 #include "BatteryIcon.h"
 #include "Symbols.h"
 
 using namespace Pinetime::Applications::Screens;
 
-const char* BatteryIcon::GetBatteryIcon(int batteryPercent) {
+const char* BatteryIcon::GetBatteryIcon(uint8_t batteryPercent) {
   if (batteryPercent > 90)
     return Symbols::batteryFull;
   if (batteryPercent > 75)

src/displayapp/screens/BatteryIcon.h

@@ -6,7 +6,7 @@ namespace Pinetime {
       class BatteryIcon {
       public:
         static const char* GetUnknownIcon();
-        static const char* GetBatteryIcon(int batteryPercent);
+        static const char* GetBatteryIcon(uint8_t batteryPercent);
         static const char* GetPlugIcon(bool isCharging);
       };
     }

src/displayapp/screens/BatteryInfo.cpp

@@ -38,11 +38,7 @@ BatteryInfo::BatteryInfo(Pinetime::Applications::DisplayApp* app, Pinetime::Cont
 
   percent = lv_label_create(lv_scr_act(), nullptr);
   lv_obj_set_style_local_text_font(percent, LV_LABEL_PART_MAIN, LV_STATE_DEFAULT, &jetbrains_mono_76);
-  if (batteryPercent >= 0) {
   lv_label_set_text_fmt(percent, "%02i%%", batteryPercent);
-  } else {
-    lv_label_set_text(percent, "--%");
-  }
   lv_label_set_align(percent, LV_LABEL_ALIGN_LEFT);
   lv_obj_align(percent, nullptr, LV_ALIGN_CENTER, 0, -60);
 
@@ -72,7 +68,6 @@ BatteryInfo::~BatteryInfo() {
 void BatteryInfo::UpdateAnim() {
   batteryPercent = batteryController.PercentRemaining();
 
-  if (batteryPercent >= 0) {
   if (batteryController.IsCharging() and batteryPercent < 100) {
     animation += 1;
     if (animation >= 100) {
@@ -90,7 +85,6 @@ void BatteryInfo::UpdateAnim() {
 
   lv_bar_set_value(charging_bar, animation, LV_ANIM_OFF);
 }
-}
 
 void BatteryInfo::UpdateScreen() {
 
@@ -99,7 +93,6 @@ void BatteryInfo::UpdateScreen() {
   batteryPercent = batteryController.PercentRemaining();
   batteryVoltage = batteryController.Voltage();
 
-  if (batteryPercent >= 0) {
   if (batteryController.IsCharging() and batteryPercent < 100) {
     lv_obj_set_style_local_bg_color(charging_bar, LV_BAR_PART_INDIC, LV_STATE_DEFAULT, LV_COLOR_RED);
     lv_label_set_text_static(status, "Battery charging");
@@ -116,11 +109,6 @@ void BatteryInfo::UpdateScreen() {
 
   lv_label_set_text_fmt(percent, "%02i%%", batteryPercent);
 
-  } else {
-    lv_label_set_text_static(status, "Reading Battery status");
-    lv_label_set_text(percent, "--%");
-  }
-
   lv_obj_align(status, charging_bar, LV_ALIGN_OUT_BOTTOM_MID, 0, 20);
   lv_label_set_text_fmt(voltage, "%1i.%02i volts", batteryVoltage / 1000, batteryVoltage % 1000 / 10);
 }

src/displayapp/screens/BatteryInfo.h

@@ -36,7 +36,7 @@ namespace Pinetime {
         lv_task_t* taskAnim;
 
         int8_t animation = 0;
-        int8_t batteryPercent = -1;
+        uint8_t batteryPercent = 0;
         uint16_t batteryVoltage = 0;
       };
     }

src/displayapp/screens/PineTimeStyle.h

@@ -42,7 +42,7 @@ namespace Pinetime {
         Pinetime::Controllers::DateTime::Days currentDayOfWeek = Pinetime::Controllers::DateTime::Days::Unknown;
         uint8_t currentDay = 0;
 
-        DirtyValue<int> batteryPercentRemaining {};
+        DirtyValue<uint8_t> batteryPercentRemaining {};
         DirtyValue<bool> bleState {};
         DirtyValue<std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds>> currentDateTime {};
         DirtyValue<bool> motionSensorOk {};

src/displayapp/screens/SystemInfo.cpp

@@ -103,7 +103,7 @@ std::unique_ptr<Screen> SystemInfo::CreateScreen1() {
 }
 
 std::unique_ptr<Screen> SystemInfo::CreateScreen2() {
-  auto batteryPercent = static_cast<uint8_t>(batteryController.PercentRemaining());
+  auto batteryPercent = batteryController.PercentRemaining();
   auto resetReason = [this]() {
     switch (watchdog.ResetReason()) {
       case Drivers::Watchdog::ResetReasons::Watchdog:

src/displayapp/screens/WatchFaceAnalog.cpp

@@ -165,7 +165,6 @@ void WatchFaceAnalog::UpdateClock() {
 }
 
 bool WatchFaceAnalog::Refresh() {
-
   batteryPercentRemaining = batteryController.PercentRemaining();
   if (batteryPercentRemaining.IsUpdated()) {
     auto batteryPercent = batteryPercentRemaining.Get();

src/displayapp/screens/WatchFaceAnalog.h

@@ -48,7 +48,7 @@ namespace Pinetime {
         Pinetime::Controllers::DateTime::Days currentDayOfWeek = Pinetime::Controllers::DateTime::Days::Unknown;
         uint8_t currentDay = 0;
 
-        DirtyValue<float> batteryPercentRemaining {0};
+        DirtyValue<uint8_t> batteryPercentRemaining {0};
         DirtyValue<std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds>> currentDateTime;
         DirtyValue<bool> notificationState {false};
 

src/displayapp/screens/WatchFaceDigital.h

@@ -45,7 +45,7 @@ namespace Pinetime {
         Pinetime::Controllers::DateTime::Days currentDayOfWeek = Pinetime::Controllers::DateTime::Days::Unknown;
         uint8_t currentDay = 0;
 
-        DirtyValue<int> batteryPercentRemaining {};
+        DirtyValue<uint8_t> batteryPercentRemaining {};
         DirtyValue<bool> bleState {};
         DirtyValue<std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds>> currentDateTime {};
         DirtyValue<bool> motionSensorOk {};

src/systemtask/SystemTask.cpp

@@ -330,6 +330,11 @@ void SystemTask::Work() {
       }
     }
 
+    if (xTaskGetTickCount() - batteryNotificationTick > batteryNotificationPeriod) {
+      nimbleController.NotifyBatteryLevel(batteryController.PercentRemaining());
+      batteryNotificationTick = xTaskGetTickCount();
+    }
+
     monitor.Process();
     uint32_t systick_counter = nrf_rtc_counter_get(portNRF_RTC_REG);
     dateTimeController.UpdateTime(systick_counter);

src/systemtask/SystemTask.h

@@ -135,6 +135,8 @@ namespace Pinetime {
       void GoToRunning();
       void UpdateMotion();
       bool stepCounterMustBeReset = false;
+      static constexpr TickType_t batteryNotificationPeriod = 1000 * 60 * 10; // 1 tick ~= 1ms. 1ms * 60 * 10 = 10 minutes
+      TickType_t batteryNotificationTick = 0;
 
 #if configUSE_TRACE_FACILITY == 1
       SystemMonitor<FreeRtosMonitor> monitor;