battery percentage

Firmware/components/backend-esp/include/cardboy/backend/esp/bat_mon.hpp

@@ -18,6 +18,7 @@ public:
     float          get_voltage() const;
     float          get_charge() const;
     float          get_current() const;
+    float          get_percentage() const;
 
     void pooler(); // FIXME:
 private:
@@ -33,6 +34,7 @@ private:
     volatile float _voltage;
     volatile float _current;
     volatile float _charge;
+    volatile float _percentage;
 
     TaskHandle_t _pooler_task;
 };

Firmware/components/backend-esp/src/bat_mon.cpp

@@ -48,6 +48,8 @@ static constexpr uint16_t DesignCapMah = 180; // 100mOhm
 
 constexpr float mahToCap(float mah) { return mah * (1000.0 / 5.0) * RSense; }
 constexpr float capToMah(uint16_t cap) { return cap * (5.0 / 1000.0) / RSense; }
+// lsb is 1/256%
+constexpr float regToPercent(uint16_t reg) { return static_cast<float>(reg) / 256.0f; }
 constexpr float regToCurrent(uint16_t reg) {
     return static_cast<float>(static_cast<int16_t>(reg)) * 0.0015625f / RSense; // Convert to mA
 }
@@ -103,6 +105,7 @@ void BatMon::pooler() {
         _charge  = capToMah(ReadRegister(0x05));
         _current = regToCurrent(ReadRegister(0x0B));
         _voltage = regToVoltage(ReadRegister(0x09));
+        _percentage = regToPercent(ReadRegister(0x06));
         vTaskDelay(pdMS_TO_TICKS(10000));
         if (_voltage < 3.0f) {
             Shutdowner::get().shutdown();
@@ -113,3 +116,4 @@ void BatMon::pooler() {
 float BatMon::get_voltage() const { return _voltage; }
 float BatMon::get_charge() const { return _charge; }
 float BatMon::get_current() const { return _current; }
+float BatMon::get_percentage() const { return _percentage; }

Firmware/components/backend-esp/src/esp_backend.cpp

@@ -78,6 +78,7 @@ public:
     [[nodiscard]] float voltage() const override { return BatMon::get().get_voltage(); }
     [[nodiscard]] float charge() const override { return BatMon::get().get_charge(); }
     [[nodiscard]] float current() const override { return BatMon::get().get_current(); }
+    [[nodiscard]] float percentage() const override { return BatMon::get().get_percentage(); }
 };
 
 class EspRuntime::StorageService final : public cardboy::sdk::IStorage {

Firmware/sdk/apps/lockscreen/src/lockscreen_app.cpp

@@ -7,6 +7,7 @@
 
 #include <algorithm>
 #include <array>
+#include <cmath>
 #include <cstdio>
 #include <ctime>
 #include <string>
@@ -446,6 +447,18 @@ private:
 
         framebuffer.frameReady();
 
+        if (auto* battery = context.battery(); battery && battery->hasData()) {
+            const float percentage = battery->percentage();
+            if (std::isfinite(percentage) && percentage >= 0.0f) {
+                char pct[8];
+                std::snprintf(pct, sizeof(pct), "%.0f%%", static_cast<double>(percentage));
+                const int pctWidth = font16x8::measureText(pct, 1, 1);
+                const int pctX     = framebuffer.width() - pctWidth - 4;
+                const int pctY     = 4;
+                font16x8::drawText(framebuffer, pctX, pctY, pct, 1, true, 1);
+            }
+        }
+
         const int scaleTime      = 4;
         const int scaleSeconds   = 2;
         const int scaleSmall     = 1;

Firmware/sdk/backend_interface/include/cardboy/sdk/services.hpp

@@ -39,6 +39,7 @@ public:
     [[nodiscard]] virtual float voltage() const { return 0.0f; }
     [[nodiscard]] virtual float charge() const { return 0.0f; }
     [[nodiscard]] virtual float current() const { return 0.0f; }
+    [[nodiscard]] virtual float percentage() const { return 0.0f; }
 };
 
 class IStorage {

Firmware/sdk/backends/desktop/include/cardboy/backend/desktop_backend.hpp

@@ -40,7 +40,6 @@ public:
 class DesktopBattery final : public cardboy::sdk::IBatteryMonitor {
 public:
     [[nodiscard]] bool hasData() const override { return false; }
-};
 
     class DesktopStorage final : public cardboy::sdk::IStorage {
     public:

Firmware/sdk/core/src/status_bar.cpp

@@ -52,14 +52,10 @@ std::string StatusBar::prepareRightText() const {
     if (_services->battery && _services->battery->hasData()) {
         const float current    = _services->battery->current();
         const float chargeMah  = _services->battery->charge();
-        const float fallbackV = _services->battery->voltage();
+        const float percentage = _services->battery->percentage();
         char        buf[64];
-        if (std::isfinite(current) && std::isfinite(chargeMah)) {
+        std::snprintf(buf, sizeof(buf), "%.2fmA %.2fmAh %.0f%%", static_cast<double>(current),
-            std::snprintf(buf, sizeof(buf), "cur %.2fmA chr %.2fmAh", static_cast<double>(current),
+                      static_cast<double>(chargeMah), static_cast<double>(percentage));
-                          static_cast<double>(chargeMah));
-        } else {
-            std::snprintf(buf, sizeof(buf), "vol %.2fV", static_cast<double>(fallbackV));
-        }
         right.assign(buf);
     }