more cleanup

Firmware/.gitignore

@@ -1,3 +1,4 @@
 build
 cmake-build*
 .idea
+.cache

Firmware/.vscode/c_cpp_properties.json

@@ -0,0 +1,23 @@
+{
+    "configurations": [
+        {
+            "name": "ESP-IDF",
+            "compilerPath": "${config:idf.toolsPath}/tools/riscv32-esp-elf/esp-14.2.0_20241119/riscv32-esp-elf/bin/riscv32-esp-elf-gcc",
+            "compileCommands": "${config:idf.buildPath}/compile_commands.json",
+            "includePath": [
+                "${config:idf.espIdfPath}/components/**",
+                "${config:idf.espIdfPathWin}/components/**",
+                "${workspaceFolder}/**"
+            ],
+            "browse": {
+                "path": [
+                    "${config:idf.espIdfPath}/components",
+                    "${config:idf.espIdfPathWin}/components",
+                    "${workspaceFolder}"
+                ],
+                "limitSymbolsToIncludedHeaders": true
+            }
+        }
+    ],
+    "version": 4
+}

Firmware/.vscode/launch.json

@@ -0,0 +1,15 @@
+{
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "type": "gdbtarget",
+      "request": "attach",
+      "name": "Eclipse CDT GDB Adapter"
+    },
+    {
+      "type": "espidf",
+      "name": "Launch",
+      "request": "launch"
+    }
+  ]
+}

Firmware/.vscode/settings.json

@@ -0,0 +1,4 @@
+{
+  "idf.flashType": "JTAG",
+  "idf.port": "/dev/tty.usbmodem12401"
+}

Firmware/components/sdk-esp/CMakeLists.txt

@@ -0,0 +1,5 @@
+idf_component_register()
+
+add_subdirectory("${CMAKE_CURRENT_LIST_DIR}/../../sdk" cb-sdk-build)
+
+target_link_libraries(${COMPONENT_LIB} INTERFACE cbsdk)

Firmware/main/CMakeLists.txt

@@ -1,5 +1,5 @@
 idf_component_register(SRCS
-        src/hello_world_main.cpp
+        src/app_main.cpp
         src/display.cpp
         src/bat_mon.cpp
         src/spi_global.cpp
@@ -9,5 +9,5 @@ idf_component_register(SRCS
         src/shutdowner.cpp
         src/buttons.cpp
         src/power_helper.cpp
-        PRIV_REQUIRES spi_flash esp_driver_i2c driver
+        PRIV_REQUIRES spi_flash esp_driver_i2c driver sdk-esp esp_timer
         INCLUDE_DIRS "include")

Firmware/main/include/bat_mon.hpp

@@ -20,9 +20,10 @@ public:
     void pooler(); // FIXME:
 private:
     static inline i2c_device_config_t _dev_cfg = {
-            .dev_addr_length = I2C_ADDR_BIT_LEN_7,
-            .device_address  = 0x70,
-            .scl_speed_hz    = 100000,
+        .dev_addr_length = I2C_ADDR_BIT_LEN_7,
+        .device_address  = 0x36,
+        .scl_speed_hz    = 100000,
+        .flags           = 0,
     };
 
     BatMon();

Firmware/main/include/buttons.hpp

@@ -9,14 +9,14 @@
 #include "freertos/task.h"
 
 typedef enum {
-    L1 = 1 << 1,
-    L2 = 1 << 6,
-    L3 = 1 << 0,
-    L4 = 1 << 7,
-    R1 = 1 << 5,
-    R2 = 1 << 2,
-    R3 = 1 << 4,
-    R4 = 1 << 3,
+    BTN_START  = 1 << 1,
+    BTN_DOWN   = 1 << 6,
+    BTN_SELECT = 1 << 0,
+    BTN_LEFT   = 1 << 7,
+    BTN_UP     = 1 << 5,
+    BTN_B      = 1 << 2,
+    BTN_RIGHT  = 1 << 4,
+    BTN_A      = 1 << 3,
 } btn_num;
 
 class Buttons {
@@ -24,12 +24,14 @@ public:
     static Buttons& get();
     void            pooler(); // FIXME:
     uint8_t         get_pressed();
+    void install_isr();
+
+    TaskHandle_t     _pooler_task;
 
 private:
     Buttons();
 
     volatile uint8_t _current;
-    TaskHandle_t     _pooler_task;
 };
 
 

Firmware/main/include/config.hpp

@@ -7,10 +7,11 @@
 #define I2C_SCL GPIO_NUM_8
 #define I2C_SDA GPIO_NUM_9
 
-#define SPI_MOSI    GPIO_NUM_5
-#define SPI_MISO    GPIO_NUM_0
-#define SPI_SCK     GPIO_NUM_4
-#define SPI_DISP_CS GPIO_NUM_11
+#define SPI_MOSI      GPIO_NUM_5
+#define SPI_MISO      GPIO_NUM_0
+#define SPI_SCK       GPIO_NUM_4
+#define SPI_DISP_CS   GPIO_NUM_24
+#define SPI_DISP_DISP GPIO_NUM_11
 
 #define SPI_BUS SPI2_HOST
 
@@ -20,10 +21,6 @@
 #define PWR_INT  GPIO_NUM_10
 #define PWR_KILL GPIO_NUM_12
 
-#define SHR_OUT GPIO_NUM_23
-#define SHR_CLK GPIO_NUM_3
-#define SHR_SH  GPIO_NUM_2
-
-#define DIRECT_BTN GPIO_NUM_1
+#define EXP_INT GPIO_NUM_1
 
 #endif

Firmware/main/include/disp_tools.hpp

@@ -4,24 +4,46 @@
 
 #ifndef CB_DISP_TOOLS_HPP
 #define CB_DISP_TOOLS_HPP
+
 #include <display.hpp>
 
+namespace DispTools {
+    static void clear() {
+        for (int y = 0; y < DISP_HEIGHT; y++) {
+            for (int x = 0; x < DISP_WIDTH; x++) {
+                SMD::set_pixel(x, y, true);
+            }
+        }
+    }
+    static bool get_pixel(int x, int y) {
+        if (x < 0 || x >= DISP_WIDTH || y < 0 || y >= DISP_HEIGHT)
+            assert(false);
+        assert(false); // Not implemented
+        return true;
+        // return disp_frame[y][x];
+    }
+    static void reset_pixel(int x, int y) {
+        if (x < 0 || x >= DISP_WIDTH || y < 0 || y >= DISP_HEIGHT)
+            assert(false);
+        SMD::set_pixel(x, y, false);
+    }
+    static void set_pixel(int x, int y) {
+        if (x < 0 || x >= DISP_WIDTH || y < 0 || y >= DISP_HEIGHT)
+            assert(false);
 
-class DispTools {
-public:
-    static DispTools& get();
-
-    void clear();
-    bool get_pixel(int x, int y);
-    void set_pixel(int x, int y);
-    void reset_pixel(int x, int y);
-    void draw_rectangle(int x1, int y1, int x2, int y2);
-    void draw_line(int x1, int y1, int x2, int y2);
-    void draw_circle(int x, int y, int r);
-    void draw_to_display();
-
-private:
-    SMD::disp_frame_t disp_frame;
+        SMD::set_pixel(x, y, true);
+    }
+    static void set_pixel(int x, int y, bool on) {
+        if (on) {
+            set_pixel(x, y);
+        } else {
+            reset_pixel(x, y);
+        }
+    }
+    static void draw_to_display() { SMD::draw(); }
+    static void draw_to_display_async_start() { SMD::draw_async_start(); }
+    static void draw_to_display_async_wait() { SMD::draw_async_wait(); }
+    static bool draw_to_display_async_busy() { return SMD::draw_async_busy(); }
 };
 
 

Firmware/main/include/display.hpp

@@ -12,33 +12,74 @@
 #include <array>
 #include <bitset>
 
-class SMD {
+#include "Surface.hpp"
+#include "Window.hpp"
+
+namespace SMD {
+static constexpr size_t kLineBytes       = DISP_WIDTH / 8;
+static constexpr size_t kLineMultiSingle = (kLineBytes + 2);
+static constexpr size_t kLineDataBytes   = kLineMultiSingle * DISP_HEIGHT + 2;
+
+DMA_ATTR extern uint8_t dma_buf[SMD::kLineDataBytes];
+
+void init();
+void clear();
+void draw();
+// Asynchronous (DMA queued) draw API
+void draw_async_start();      // queue frame transfer if none in flight
+void draw_async_wait();       // wait for any in-flight transfer to finish
+bool draw_async_busy();       // true if a transfer is in-flight
+
+static void set_pixel(int x, int y, bool value) {
+    assert(x >= 0 && x < DISP_WIDTH && y >= 0 && y < DISP_HEIGHT);
+
+    unsigned lineIdx = 2 + kLineMultiSingle * y + (x / 8);
+    unsigned bitIdx  = 1 << (7 - (x % 8)) % 8;
+
+    if (value) {
+        dma_buf[lineIdx] &= ~bitIdx;
+    } else {
+        dma_buf[lineIdx] |= bitIdx;
+    }
+}
+
+static inline spi_device_interface_config_t _devcfg = {
+        .mode           = 0,               // SPI mode 0
+        .clock_speed_hz = 2 * 1000 * 1000, // Clock out at 10 MHz
+        .spics_io_num   = SPI_DISP_CS,     // CS pin
+        .flags          = SPI_DEVICE_POSITIVE_CS,
+        .queue_size     = 3,
+        // .pre_cb = lcd_spi_pre_transfer_callback, //Specify pre-transfer callback to handle D/C line
+};
+extern spi_device_handle_t _spi;
+extern bool                _vcom;
+extern bool                _inFlight;
+extern spi_transaction_t   _tx; // persistent transaction struct for async API
+}; // namespace SMD
+
+class SMDSurface : public Surface<SMDSurface, BwPixel>, public StandardEventQueue<SMDSurface> {
 public:
-    using disp_line_t  = std::bitset<400>;
-    using disp_frame_t = std::array<disp_line_t, 240>;
+    using PixelType = BwPixel;
 
-    static SMD& get();
-    void        clear();
-    void        draw(const disp_frame_t& frame);
+    SMDSurface(EventLoop* loop);
 
-private:
-    SMD();
-    static inline spi_device_interface_config_t _devcfg = {
-            .mode           = 0,               // SPI mode 0
-            .clock_speed_hz = 2 * 1000 * 1000, // Clock out at 10 MHz
-            .spics_io_num   = SPI_DISP_CS,     // CS pin
-            .flags          = SPI_DEVICE_POSITIVE_CS,
-            .queue_size     = 3,
-            // .pre_cb = lcd_spi_pre_transfer_callback, //Specify pre-transfer callback to handle D/C line
-    };
-    static constexpr size_t kLineBytes = DISP_WIDTH / 8;
-    spi_device_handle_t     _spi;
-    bool                    _vcom = false;
+    ~SMDSurface() override;
 
-    static constexpr size_t        kLineData = (kLineBytes + 4);
-    std::array<uint8_t, kLineData> buf{};
+    void draw_pixel_impl(unsigned x, unsigned y, const BwPixel& pixel);
 
-    std::array<uint8_t, kLineBytes> prep_line(const SMD::disp_line_t& line);
+    void clear_impl();
+
+    int get_width_impl() const;
+
+    int get_height_impl() const;
+
+    template<typename T>
+    EventHandlingResult handle(const T& event) {
+        return _window->handle(event);
+    }
+
+    EventHandlingResult handle(SurfaceResizeEvent event);
 };
 
+
 #endif // DISPLAY_HPP

Firmware/main/include/power_helper.hpp

@@ -11,10 +11,10 @@ class PowerHelper {
 public:
     static PowerHelper& get();
 
-    bool is_slow() const;
-    void set_slow(bool slow);
-    void reset_slow_isr(); // FIXME:
-    void delay(int slow_ms, int normal_ms);
+    bool       is_slow() const;
+    void       set_slow(bool slow);
+    BaseType_t reset_slow_isr(BaseType_t* xHigherPriorityTaskWoken);
+    void       delay(int slow_ms, int normal_ms);
 
     void install_isr();
 

Firmware/main/include/shutdowner.hpp

@@ -10,6 +10,7 @@ class Shutdowner {
 public:
     static Shutdowner& get();
     void install_isr();
+    void shutdown();
 private:
     Shutdowner();
 };

Firmware/main/src/bat_mon.cpp

@@ -10,6 +10,7 @@
 #include "freertos/task.h"
 
 #include "i2c_global.hpp"
+#include "shutdowner.hpp"
 
 static i2c_master_dev_handle_t dev_handle;
 
@@ -20,25 +21,78 @@ BatMon& BatMon::get() {
 
 static void start_pooler(void* arg) { static_cast<BatMon*>(arg)->pooler(); }
 
+void WriteRegister(uint8_t reg, uint16_t value) {
+    uint8_t buf2[3];
+    buf2[0] = reg;
+    buf2[1] = value & 0xFF;
+    buf2[2] = value >> 8;
+    ESP_ERROR_CHECK(i2c_master_transmit(dev_handle, buf2, sizeof(buf2), -1));
+}
+
+uint16_t ReadRegister(uint8_t reg) {
+    uint16_t buffer;
+    ESP_ERROR_CHECK(
+            i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 2, -1));
+    return buffer;
+}
+void WriteAndVerifyRegister(char RegisterAddress, int RegisterValueToWrite) {
+    int      attempt = 0;
+    uint16_t RegisterValueRead;
+    do {
+        WriteRegister(RegisterAddress, RegisterValueToWrite);
+        vTaskDelay(1 / portTICK_PERIOD_MS);
+        RegisterValueRead = ReadRegister(RegisterAddress);
+    } while (RegisterValueToWrite != RegisterValueRead && attempt++ < 3);
+}
+
+static constexpr float    RSense       = 0.1; // 100mOhm
+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; }
+constexpr float regToCurrent(uint16_t reg) {
+    return static_cast<float>(static_cast<int16_t>(reg)) * 0.0015625f / RSense; // Convert to mA
+}
+constexpr uint16_t currentToReg(float current) { return static_cast<uint16_t>(current * RSense / 0.0015625f); }
+constexpr float    regToVoltage(uint16_t reg) {
+    return reg * 0.078125f * 0.001f;                           // Convert to volts
+}
+constexpr uint16_t voltageToReg(float voltage) {
+    return static_cast<uint16_t>(voltage / (0.078125f * 0.001f)); // Convert to register value
+}
+static constexpr uint16_t DesignCap = mahToCap(DesignCapMah);
+static constexpr uint16_t IchgTerm  = currentToReg(10);
+static constexpr uint16_t VEmpty    = 0b1001011001100001; //  (3V/3.88V)
+static constexpr uint16_t dQAcc     = (DesignCap / 32);
+
 BatMon::BatMon() {
     ESP_ERROR_CHECK(i2c_master_bus_add_device(I2cGlobal::get().get_bus_handle(), &_dev_cfg, &dev_handle));
 
-    uint8_t reg = 1;
-    uint8_t buffer;
-    uint8_t buf2[2];
-
-    ESP_ERROR_CHECK(
-            i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 1, -1));
-    if (buffer & (1 << 4)) // POR reset
+    bool StatusPOR = ReadRegister(0x00) & 0x0002;
+    if (StatusPOR) // POR reset
     {
         printf("Gas gauge reset!\n");
-        buf2[0] = 1;
-        buf2[1] = 0 << 4;
-        ESP_ERROR_CHECK(i2c_master_transmit(dev_handle, buf2, sizeof(buf2), -1));
+        while (ReadRegister(0x3D) & 1)
+            vTaskDelay(10 / portTICK_PERIOD_MS);
 
-        buf2[0] = 0;
-        buf2[1] = 1 << 4 | 1 << 2; // 10 bit adc
-        ESP_ERROR_CHECK(i2c_master_transmit(dev_handle, buf2, sizeof(buf2), -1));
+        uint16_t HibCFG = ReadRegister(0xBA);           // Store original HibCFG value
+        WriteRegister(0x60, 0x90);                      // Exit Hibernate Mode step 1
+        WriteRegister(0xBA, 0x0);                       // Exit Hibernate Mode step 2
+        WriteRegister(0x60, 0x0);                       // Exit Hibernate Mode step 3
+        WriteRegister(0x18, DesignCap);                 // Write DesignCap
+        WriteRegister(0x45, DesignCap / 32);            // Write dQAcc
+        WriteRegister(0x1E, IchgTerm);                  // Write IchgTerm
+        WriteRegister(0x3A, VEmpty);                    // Write VEmpty
+        WriteRegister(0x46, dQAcc * 44138 / DesignCap); // Write dPAcc
+        WriteRegister(0xDB, 0x8000);                    // Write ModelCFG
+
+        // Poll ModelCFG.Refresh(highest bit), proceed to Step 4 when ModelCFG.Refresh = 0.
+        while (ReadRegister(0xDB) & 0x8000)
+            vTaskDelay(10 / portTICK_PERIOD_MS);       // 10ms wait loop. Do not continue until ModelCFG.Refresh == 0.
+        WriteRegister(0xBA, HibCFG);                   // Restore Original HibCFG value
+
+        uint16_t Status = ReadRegister(0x00);          // Read Status
+        WriteAndVerifyRegister(0x00, Status & 0xFFFD); // Write and Verify Status with POR bit cleared
     }
 
     xTaskCreate(&start_pooler, "BatMon", 2048, this, tskIDLE_PRIORITY, &_pooler_task);
@@ -48,28 +102,13 @@ void BatMon::pooler() {
     while (true) {
         uint8_t  reg = 8;
         uint16_t buffer;
-        ESP_ERROR_CHECK(
-                i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 2, -1));
-        float voltage = buffer;
-        voltage *= 2.44f;
-        voltage /= 1000;
-        _voltage = voltage;
-        reg      = 2;
-        ESP_ERROR_CHECK(
-                i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 2, -1));
-        float charge = *reinterpret_cast<int16_t*>(&buffer);
-        charge *= 6.70f;
-        charge /= 50;
-        _charge = charge;
-        reg     = 6;
-        ESP_ERROR_CHECK(
-                i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 2, -1));
-        float current = static_cast<int16_t>(buffer << 2);
-        current *= 11.77f;
-        current /= 50;
-        current /= 4;
-        _current = current;
+        _charge  = capToMah(ReadRegister(0x05));
+        _current = regToCurrent(ReadRegister(0x0B));
+        _voltage = regToVoltage(ReadRegister(0x09));
         PowerHelper::get().delay(10000, 1000);
+        if (_voltage < 3.0f) {
+            Shutdowner::get().shutdown();
+        }
     }
 }
 

Firmware/main/src/buttons.cpp

@@ -13,6 +13,14 @@
 #include "freertos/task.h"
 
 #include "config.hpp"
+#include "i2c_global.hpp"
+
+static i2c_master_dev_handle_t    dev_handle;
+static inline i2c_device_config_t dev_cfg = {
+        .dev_addr_length = I2C_ADDR_BIT_LEN_7,
+        .device_address  = 0x20,
+        .scl_speed_hz    = 100000,
+};
 
 Buttons& Buttons::get() {
     static Buttons buttons;
@@ -21,18 +29,48 @@ Buttons& Buttons::get() {
 
 static void start_pooler(void* arg) { static_cast<Buttons*>(arg)->pooler(); }
 
-Buttons::Buttons() {
-    ESP_ERROR_CHECK(gpio_reset_pin(SHR_OUT));
-    ESP_ERROR_CHECK(gpio_reset_pin(SHR_CLK));
-    ESP_ERROR_CHECK(gpio_reset_pin(SHR_SH));
-    ESP_ERROR_CHECK(gpio_set_direction(SHR_OUT, GPIO_MODE_INPUT));
-    ESP_ERROR_CHECK(gpio_set_pull_mode(SHR_OUT, GPIO_FLOATING));
-    ESP_ERROR_CHECK(gpio_set_direction(SHR_SH, GPIO_MODE_OUTPUT));
-    ESP_ERROR_CHECK(gpio_set_direction(SHR_CLK, GPIO_MODE_OUTPUT));
+static bool is_on_low;
 
-    xTaskCreate(&start_pooler, "ButtonsPooler", 2048, this, 1, &_pooler_task);
+static void wakeup(void* arg) {
+    if (is_on_low) {
+        ESP_ERROR_CHECK(gpio_set_intr_type(EXP_INT, GPIO_INTR_HIGH_LEVEL));
+        ESP_ERROR_CHECK(gpio_wakeup_enable(EXP_INT, GPIO_INTR_HIGH_LEVEL));
+        is_on_low = false;
+
+        BaseType_t xResult                  = pdFAIL;
+        BaseType_t xHigherPriorityTaskWoken = pdFALSE;
+
+        xTaskNotifyFromISR(Buttons::get()._pooler_task, 0, eNoAction, &xHigherPriorityTaskWoken);
+
+        PowerHelper::get().reset_slow_isr(&xHigherPriorityTaskWoken);
+        portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+    } else {
+        ESP_ERROR_CHECK(gpio_set_intr_type(EXP_INT, GPIO_INTR_LOW_LEVEL));
+        ESP_ERROR_CHECK(gpio_wakeup_enable(EXP_INT, GPIO_INTR_LOW_LEVEL));
+        is_on_low = true;
+    }
 }
 
+Buttons::Buttons() {
+    ESP_ERROR_CHECK(i2c_master_bus_add_device(I2cGlobal::get().get_bus_handle(), &dev_cfg, &dev_handle));
+    uint8_t buf2[2];
+
+    // Config
+    buf2[0] = 6;
+    buf2[1] = 0xFF;
+    ESP_ERROR_CHECK(i2c_master_transmit(dev_handle, buf2, sizeof(buf2), -1));
+    buf2[0] = 7;
+    buf2[1] = 0x80;
+    ESP_ERROR_CHECK(i2c_master_transmit(dev_handle, buf2, sizeof(buf2), -1));
+    xTaskCreate(&start_pooler, "ButtonsPooler", 2048, this, 1, &_pooler_task);
+
+    ESP_ERROR_CHECK(gpio_reset_pin(EXP_INT));
+    ESP_ERROR_CHECK(gpio_set_direction(EXP_INT, GPIO_MODE_INPUT));
+    ESP_ERROR_CHECK(gpio_set_pull_mode(EXP_INT, GPIO_FLOATING));
+    ESP_ERROR_CHECK(gpio_set_intr_type(EXP_INT, GPIO_INTR_LOW_LEVEL));
+    ESP_ERROR_CHECK(gpio_wakeup_enable(EXP_INT, GPIO_INTR_LOW_LEVEL));
+    is_on_low = true;
+}
 
 static void delay(unsigned long long loop) {
     for (unsigned long long i = 0; i < loop; i++) {
@@ -42,18 +80,17 @@ static void delay(unsigned long long loop) {
 
 void Buttons::pooler() {
     while (true) {
-        ESP_ERROR_CHECK(gpio_set_level(SHR_SH, 0));
-        ESP_ERROR_CHECK(gpio_set_level(SHR_SH, 1));
-
-        uint8_t new_val = 0;
-
-        for (int i = 0; i < 8; i++) {
-            ESP_ERROR_CHECK(gpio_set_level(SHR_CLK, 0));
-            new_val |= gpio_get_level(SHR_OUT) << i;
-            ESP_ERROR_CHECK(gpio_set_level(SHR_CLK, 1));
-        }
-        _current = new_val;
-        PowerHelper::get().delay(10000, 100);
+        BaseType_t xResult = xTaskNotifyWait(pdFALSE, ULONG_MAX, nullptr, portMAX_DELAY);
+        uint8_t    reg     = 0;
+        uint8_t    buffer;
+        ESP_ERROR_CHECK(
+                i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 1, -1));
+        _current = buffer;
+        // read second port too to clear the interrupt
+        reg = 1;
+        ESP_ERROR_CHECK(
+                i2c_master_transmit_receive(dev_handle, &reg, sizeof(reg), reinterpret_cast<uint8_t*>(&buffer), 1, -1));
     }
 }
 uint8_t Buttons::get_pressed() { return _current; }
+void    Buttons::install_isr() { gpio_isr_handler_add(EXP_INT, wakeup, nullptr); }

Firmware/main/src/disp_tools.cpp

@@ -8,68 +8,3 @@
 
 #include <display.hpp>
 
-DispTools& DispTools::get() {
-    static DispTools disp_tools;
-    return disp_tools;
-}
-
-void DispTools::clear() {
-    for (int y = 0; y < DISP_HEIGHT; y++) {
-        for (int x = 0; x < DISP_WIDTH; x++) {
-            disp_frame[y][x] = 1;
-        }
-    }
-}
-bool DispTools::get_pixel(int x, int y) { return disp_frame[y][x]; }
-void DispTools::reset_pixel(int x, int y) { disp_frame[y][x] = true; }
-void DispTools::set_pixel(int x, int y) { disp_frame[y][x] = false; }
-void DispTools::draw_rectangle(int x1, int y1, int x2, int y2) {
-    int dy = y2 - y1;
-    while (std::abs(dy) > 0) {
-        draw_line(x1, y1 + dy, x2, y1 + dy);
-        dy += (dy > 0) ? -1 : 1;
-    }
-}
-void DispTools::draw_line(int x1, int y1, int x2, int y2) {
-    int dx = x2 - x1;
-    int dy = y2 - y1;
-    int a = 0, b = 0, diff = 0;
-
-    if (dx == 0) {
-        while (dy != 0) {
-            set_pixel(x1, y1 + dy);
-            dy += (dy > 0) ? -1 : 1;
-        }
-        return;
-    }
-
-    if (dy == 0) {
-        while (dx != 0) {
-            set_pixel(x1 + dx, y1);
-            dx += (dx > 0) ? -1 : 1;
-        }
-        return;
-    }
-
-    while (std::abs(a) <= std::abs(dx) && std::abs(b) <= std::abs(dy)) {
-        set_pixel(x1 + a, y1 + b);
-        if (diff < 0) {
-            a += (dx > 0) ? 1 : -1;
-            diff += std::abs(dy);
-        } else {
-            b += (dy > 0) ? 1 : -1;
-            diff -= std::abs(dx);
-        }
-    }
-}
-void DispTools::draw_circle(int x, int y, int r) {
-    if (r > 181)
-        return;
-    int dy = -r;
-    while (dy <= r) {
-        int dx = static_cast<int>(std::sqrt(r * r - dy * dy));
-        draw_line(x - dx, y + dy, x + dx, y + dy);
-        dy++;
-    }
-}
-void DispTools::draw_to_display() { SMD::get().draw(disp_frame); }

Firmware/main/src/disp_tty.cpp

@@ -13,9 +13,9 @@ void FbTty::draw_char(int col, int row) {
         for (int y = 0; y < 16; y++) {
             bool color = fonts_Terminess_Powerline[_buf[col][row]][y] & (1 << (8 - x));
             if (color)
-                DispTools::get().set_pixel(col * 8 + x, row * 16 + y);
+                DispTools::set_pixel(col * 8 + x, row * 16 + y);
             else
-                DispTools::get().reset_pixel(col * 8 + x, row * 16 + y);
+                DispTools::reset_pixel(col * 8 + x, row * 16 + y);
         }
     }
 }

Firmware/main/src/display.cpp

@@ -6,29 +6,36 @@
 
 #include <cstring>
 
+#include <driver/gpio.h>
 #include "driver/spi_master.h"
 
+#include "disp_tools.hpp"
+
+DMA_ATTR uint8_t    SMD::dma_buf[SMD::kLineDataBytes]{};
+spi_device_handle_t SMD::_spi;
+bool                SMD::_vcom    = false;
+bool                SMD::_inFlight = false;
+spi_transaction_t   SMD::_tx{};
+
 // This solution is attributed to Rich Schroeppel in the Programming Hacks section
 // TODO: Why does the device flag not work?
 unsigned char reverse_bits3(unsigned char b) { return (b * 0x0202020202ULL & 0x010884422010ULL) % 0x3ff; }
 
-std::array<uint8_t, SMD::kLineBytes> SMD::prep_line(const SMD::disp_line_t& line) {
-    std::array<uint8_t, kLineBytes> data{};
-    for (int i = 0; i < DISP_WIDTH; i++) {
-        data[i / 8] = data[i / 8] | (line[i] << (i % 8));
-    }
-    for (int i = 0; i < kLineBytes; i++) {
-        data[i] = reverse_bits3(data[i]);
-    }
-    return data;
-}
 
-SMD& SMD::get() {
-    static SMD smd;
-    return smd;
-}
+void SMD::init() {
+    spi_bus_add_device(SPI_BUS, &_devcfg, &_spi);
+    ESP_ERROR_CHECK(gpio_reset_pin(SPI_DISP_DISP));
 
-SMD::SMD() { spi_bus_add_device(SPI_BUS, &_devcfg, &_spi); }
+    ESP_ERROR_CHECK(gpio_set_direction(SPI_DISP_DISP, GPIO_MODE_OUTPUT));
+    ESP_ERROR_CHECK(gpio_set_level(SPI_DISP_DISP, 1));
+    ESP_ERROR_CHECK(gpio_hold_en(SPI_DISP_DISP));
+
+    for (uint8_t i = 0; i < DISP_HEIGHT; i++) {
+        dma_buf[kLineMultiSingle * i + 1]              = reverse_bits3(i + 1);
+        dma_buf[2 + kLineMultiSingle * i + kLineBytes] = 0;
+    }
+    dma_buf[kLineDataBytes - 1] = 0;
+}
 
 void SMD::clear() {
     std::array<uint8_t, 2> buf{};
@@ -40,23 +47,61 @@ void SMD::clear() {
     ESP_ERROR_CHECK(spi_device_transmit(_spi, &t));
 }
 
-void SMD::draw(const disp_frame_t& frame) {
-    _vcom = !_vcom;
-    for (uint8_t i = 0; i < DISP_HEIGHT; i++) {
-        spi_transaction_t t{};
-
-        t.tx_buffer = buf.data();
-        t.length    = buf.size() * 8;
-
-        buf[0] = 0b10000000 | (_vcom << 6);
-        buf[1] = reverse_bits3(i + 1);
-
-        auto prepared = prep_line(frame.at(i));
-        memcpy(buf.data() + 2, prepared.data(), kLineBytes);
-
-        buf[2 + kLineBytes]     = 0;
-        buf[2 + kLineBytes + 1] = 0;
-
-        ESP_ERROR_CHECK(spi_device_transmit(_spi, &t));
-    }
+void SMD::draw() {
+    // Synchronous (blocking) version retained for compatibility
+    _vcom      = !_vcom;
+    _tx        = {};
+    _tx.tx_buffer = dma_buf;
+    _tx.length    = SMD::kLineDataBytes * 8;
+    dma_buf[0]    = 0b10000000 | (_vcom << 6);
+    ESP_ERROR_CHECK(spi_device_transmit(_spi, &_tx));
 }
+
+bool SMD::draw_async_busy() { return _inFlight; }
+
+void SMD::draw_async_start() {
+    if (_inFlight)
+        return; // already in flight
+    _vcom      = !_vcom;
+    _tx        = {};
+    _tx.tx_buffer = dma_buf;
+    _tx.length    = SMD::kLineDataBytes * 8;
+    dma_buf[0]    = 0b10000000 | (_vcom << 6);
+    esp_err_t err = spi_device_queue_trans(_spi, &_tx, 0);
+    if (err == ESP_OK)
+        _inFlight = true;
+    else
+        ESP_ERROR_CHECK(err);
+}
+
+void SMD::draw_async_wait() {
+    if (!_inFlight)
+        return;
+    spi_transaction_t* r = nullptr;
+    esp_err_t          err;
+    // Wait indefinitely; could add timeout handling if desired
+    err = spi_device_get_trans_result(_spi, &r, portMAX_DELAY);
+    ESP_ERROR_CHECK(err);
+    _inFlight = false;
+}
+
+void SMDSurface::draw_pixel_impl(unsigned x, unsigned y, const BwPixel& pixel) {
+    if (pixel.on)
+        DispTools::set_pixel(x, y);
+    else
+        DispTools::reset_pixel(x, y);
+}
+
+void SMDSurface::clear_impl() { DispTools::clear(); }
+
+int SMDSurface::get_width_impl() const { return DISP_WIDTH; }
+
+int SMDSurface::get_height_impl() const { return DISP_HEIGHT; }
+
+EventHandlingResult SMDSurface::handle(SurfaceResizeEvent event) { return _window->handle(event); }
+
+SMDSurface::SMDSurface(EventLoop* loop) :
+    Surface<SMDSurface, BwPixel>(),
+    EventQueue<SMDSurface, KeyboardEvent, SurfaceEvent, SurfaceResizeEvent>(loop, this) {}
+
+SMDSurface::~SMDSurface() {}

Firmware/main/src/hello_world_main.cpp

@@ -1,119 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2010-2022 Espressif Systems (Shanghai) CO LTD
- *
- * SPDX-License-Identifier: CC0-1.0
- */
-
-#include <buttons.hpp>
-#include <cstdint>
-#include <disp_tools.hpp>
-#include <disp_tty.hpp>
-#include <esp_pm.h>
-#include <inttypes.h>
-#include <stdio.h>
-#include "esp_chip_info.h"
-#include "esp_flash.h"
-#include "esp_system.h"
-#include "freertos/FreeRTOS.h"
-#include "freertos/task.h"
-#include "sdkconfig.h"
-
-#include "display.hpp"
-
-#include "bat_mon.hpp"
-#include "driver/i2c_master.h"
-#include "driver/spi_master.h"
-#include "i2c_global.hpp"
-
-#include <driver/gpio.h>
-#include <esp_sleep.h>
-#include <memory>
-#include <power_helper.hpp>
-#include <shutdowner.hpp>
-#include <spi_global.hpp>
-#include <string>
-
-FbTty tty;
-
-
-extern "C" void app_main() {
-    esp_pm_config_t pm_config = {
-            .max_freq_mhz = CONFIG_ESP_DEFAULT_CPU_FREQ_MHZ, .min_freq_mhz = 16, .light_sleep_enable = true};
-    ESP_ERROR_CHECK(esp_pm_configure(&pm_config));
-    printf("Hello world!\n");
-    // TODO: Where to put that?
-    ESP_ERROR_CHECK(esp_sleep_enable_gpio_wakeup());
-    // For some reason, calling it here hangs on startup, sometimes
-    // ESP_ERROR_CHECK(gpio_install_isr_service(0));
-    PowerHelper::get();
-    Shutdowner::get();
-    ESP_ERROR_CHECK(gpio_install_isr_service(0));
-    Shutdowner::get().install_isr();
-    PowerHelper::get().install_isr();
-    Buttons::get();
-    I2cGlobal::get();
-    BatMon::get();
-    SpiGlobal::get();
-    SMD::get();
-    SMD::get().clear();
-    DispTools::get().clear();
-    DispTools::get().draw_line(0, 0, 400, 240);
-    DispTools::get().draw_circle(100, 100, 20);
-    DispTools::get().draw_to_display();
-    tty.putstr("Hello\nworld!");
-    DispTools::get().draw_to_display();
-
-    int rx = 30, ry = 30;
-
-    int lastmove = 0;
-
-    while (true) {
-        // SMD::clear();
-        // printf("Voltage: %f\n", BatMon::get_voltage());
-        DispTools::get().clear();
-        tty.reset();
-
-        uint8_t pressed = Buttons::get().get_pressed();
-        if (pressed & L3)
-            rx -= 5;
-        if (pressed & L4)
-            ry += 5;
-        if (pressed & R3)
-            ry -= 5;
-        if (pressed & R4)
-            rx += 5;
-
-        if (pressed == 0 && !PowerHelper::get().is_slow())
-            lastmove++;
-        else if (pressed != 0) {
-            lastmove = 0;
-            PowerHelper::get().set_slow(false);
-        }
-
-        if (lastmove > 20) {
-            lastmove = 0;
-            PowerHelper::get().set_slow(true);
-        }
-
-        bool slow = PowerHelper::get().is_slow();
-        tty.fmt("{:.1f}mA {:.1f}V {:.1f}mAh {}", BatMon::get().get_current(), BatMon::get().get_voltage(),
-                BatMon::get().get_charge(), slow ? "S" : "");
-
-        if (rx < 30)
-            rx = 30;
-        if (rx > 370)
-            rx = 370;
-        if (ry < 30)
-            ry = 30;
-        if (ry > 210)
-            ry = 210;
-        // tty.fmt("Button: {}", pressed);
-        DispTools::get().draw_circle(rx, ry, 20);
-        // printf("Restarting in %d seconds...\n", i);
-        DispTools::get().draw_to_display();
-        PowerHelper::get().delay(10000, 30);
-    }
-    // printf("Restarting now.\n");
-    // fflush(stdout);
-    // esp_restart();
-}

Firmware/main/src/power_helper.cpp

@@ -25,32 +25,22 @@ void PowerHelper::set_slow(bool slow) {
     }
 }
 
-void PowerHelper::reset_slow_isr() {
+BaseType_t PowerHelper::reset_slow_isr(BaseType_t* xHigherPriorityTaskWoken) {
+    _slow = false;
+    return xEventGroupSetBitsFromISR(_event_group, 1, xHigherPriorityTaskWoken);
+}
+
+static void wakeup(void* arg) {
     BaseType_t xHigherPriorityTaskWoken, xResult;
 
     xHigherPriorityTaskWoken = pdFALSE;
-
-    _slow   = false;
-    xResult = xEventGroupSetBitsFromISR(_event_group, 1, &xHigherPriorityTaskWoken);
-
+    xResult                  = static_cast<PowerHelper*>(arg)->reset_slow_isr(&xHigherPriorityTaskWoken);
     if (xResult != pdFAIL) {
         portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
-    }
+    };
 }
 
-static void wakeup(void* arg) { static_cast<PowerHelper*>(arg)->reset_slow_isr(); }
-
-PowerHelper::PowerHelper() : _event_group(xEventGroupCreate()) {
-    ESP_ERROR_CHECK(gpio_reset_pin(DIRECT_BTN));
-    ESP_ERROR_CHECK(gpio_set_direction(DIRECT_BTN, GPIO_MODE_INPUT));
-    ESP_ERROR_CHECK(gpio_set_pull_mode(DIRECT_BTN, GPIO_FLOATING));
-    ESP_ERROR_CHECK(gpio_set_intr_type(DIRECT_BTN, GPIO_INTR_HIGH_LEVEL));
-    ESP_ERROR_CHECK(gpio_wakeup_enable(DIRECT_BTN, GPIO_INTR_HIGH_LEVEL));
-    // ESP_ERROR_CHECK(gpio_install_isr_service(0));
-    // gpio_isr_handler_add(DIRECT_BTN, wakeup, this);
-
-    set_slow(false);
-}
+PowerHelper::PowerHelper() : _event_group(xEventGroupCreate()) { set_slow(false); }
 
 void PowerHelper::delay(int slow_ms, int normal_ms) {
     if (is_slow()) {
@@ -67,4 +57,6 @@ void PowerHelper::delay(int slow_ms, int normal_ms) {
         vTaskDelay(normal_ms / portTICK_PERIOD_MS);
     }
 }
-void PowerHelper::install_isr() { gpio_isr_handler_add(DIRECT_BTN, wakeup, this); }
+void PowerHelper::install_isr() {
+    // gpio_isr_handler_add(EXP_INT, wakeup, this);
+}

Firmware/main/src/shutdowner.cpp

@@ -14,26 +14,31 @@ Shutdowner& Shutdowner::get() {
     return instance;
 }
 
-static void IRAM_ATTR shutdown(void* arg) {
+static void IRAM_ATTR int_shutdown(void* arg) {
     // printf("Shutting down...\n");
     ESP_ERROR_CHECK(gpio_hold_dis(PWR_KILL));
     ESP_ERROR_CHECK(gpio_set_level(PWR_KILL, 0));
 }
 
-Shutdowner::Shutdowner() {
-    ESP_ERROR_CHECK(gpio_reset_pin(PWR_INT));
-    ESP_ERROR_CHECK(gpio_reset_pin(PWR_KILL));
+void Shutdowner::shutdown() {
+    ESP_ERROR_CHECK(gpio_hold_dis(PWR_KILL));
+    ESP_ERROR_CHECK(gpio_set_level(PWR_KILL, 0));
+}
 
-    ESP_ERROR_CHECK(gpio_set_direction(PWR_INT, GPIO_MODE_INPUT));
+Shutdowner::Shutdowner() {
+    ESP_ERROR_CHECK(gpio_reset_pin(PWR_KILL));
     ESP_ERROR_CHECK(gpio_set_direction(PWR_KILL, GPIO_MODE_OUTPUT));
     ESP_ERROR_CHECK(gpio_set_level(PWR_KILL, 1));
+    ESP_ERROR_CHECK(gpio_hold_en(PWR_KILL));
+
+    ESP_ERROR_CHECK(gpio_reset_pin(PWR_INT));
+    ESP_ERROR_CHECK(gpio_set_direction(PWR_INT, GPIO_MODE_INPUT));
     ESP_ERROR_CHECK(gpio_set_pull_mode(PWR_INT, GPIO_FLOATING));
     ESP_ERROR_CHECK(gpio_set_intr_type(PWR_INT, GPIO_INTR_LOW_LEVEL));
     // ESP_ERROR_CHECK(esp_sleep_enable_gpio_wakeup());
     ESP_ERROR_CHECK(gpio_wakeup_enable(PWR_INT, GPIO_INTR_LOW_LEVEL));
     // ESP_ERROR_CHECK(gpio_install_isr_service(0));
-    ESP_ERROR_CHECK(gpio_hold_en(PWR_KILL));
     // gpio_isr_handler_add(PWR_INT, shutdown, nullptr);
 }
 
-void Shutdowner::install_isr() { gpio_isr_handler_add(PWR_INT, shutdown, nullptr); }
+void Shutdowner::install_isr() { gpio_isr_handler_add(PWR_INT, int_shutdown, nullptr); }

Firmware/sdk/.clang-format

@@ -0,0 +1,76 @@
+# Generated from CLion C/C++ Code Style settings
+---
+Language: Cpp
+BasedOnStyle: LLVM
+AccessModifierOffset: -4
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: false
+AlignConsecutiveBitFields:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: false
+AlignConsecutiveDeclarations:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: false
+AlignConsecutiveMacros:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: false
+AlignTrailingComments:
+  Kind: Always
+  OverEmptyLines: 2
+SpacesBeforeTrailingComments: 1
+AlignOperands: Align
+AlignEscapedNewlines: Right
+AlwaysBreakTemplateDeclarations: Yes
+BraceWrapping:
+  AfterCaseLabel: false
+  AfterClass: false
+  AfterControlStatement: false
+  AfterEnum: false
+  AfterFunction: false
+  AfterNamespace: false
+  AfterStruct: false
+  AfterUnion: false
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  BeforeLambdaBody: false
+  BeforeWhile: false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBraces: Custom
+BreakConstructorInitializers: AfterColon
+BreakConstructorInitializersBeforeComma: false
+ColumnLimit: 120
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+ContinuationIndentWidth: 8
+IncludeCategories:
+  - Regex: '^<.*'
+    Priority: 1
+  - Regex: '^".*'
+    Priority: 2
+  - Regex: '.*'
+    Priority: 3
+IncludeIsMainRegex: '([-_](test|unittest))?$'
+IndentCaseLabels: true
+IndentWidth: 4
+InsertNewlineAtEOF: true
+MacroBlockBegin: ''
+MacroBlockEnd: ''
+MaxEmptyLinesToKeep: 2
+PointerAlignment: Left
+SpaceAfterCStyleCast: true
+SpaceAfterTemplateKeyword: false
+SpaceBeforeRangeBasedForLoopColon: false
+SpaceInEmptyParentheses: false
+SpacesInAngles: false
+SpacesInConditionalStatement: false
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+...

Firmware/sdk/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.10)
+project(sdk-top)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED YES)
+
+add_subdirectory(library)
+if (NOT CMAKE_CROSSCOMPILING)
+    add_subdirectory(sfml-port)
+    add_subdirectory(examples)
+endif ()

Firmware/sdk/library/CMakeLists.txt

@@ -0,0 +1,22 @@
+cmake_minimum_required(VERSION 3.10)
+
+add_library(cbsdk
+        src/Window.cpp
+        include_public/Window.hpp
+        include_public/Pixel.hpp
+        src/Event.cpp
+        include_public/Event.hpp
+        include_public/StandardEvents.hpp
+        include_public/Surface.hpp
+        include_public/Fonts.hpp
+        src/TextWindow.cpp
+        include_public/TextWindow.hpp
+        include_public/utils.hpp
+        include_public/SubSurface.hpp)
+
+target_include_directories(cbsdk PUBLIC include_public)
+target_include_directories(cbsdk PRIVATE include)
+
+if (NOT CMAKE_CROSSCOMPILING)
+    add_subdirectory(test)
+endif ()

Firmware/sdk/library/include_public/Event.hpp

@@ -0,0 +1,139 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef EVENT_HPP
+#define EVENT_HPP
+
+#include <algorithm>
+#include <concepts>
+#include <condition_variable>
+#include <list>
+#include <mutex>
+#include <optional>
+#include <type_traits>
+#include <variant>
+#include <functional>
+
+enum class EventHandlingResult { DONE, IGNORE, CONTINUE };
+
+class Event {};
+
+struct LoopQuitEvent : public Event {};
+
+template<typename T>
+concept IsEvent = std::is_base_of_v<Event, T>;
+
+template<typename H, typename E>
+concept HasHandleFor = requires(H h, E e) {
+    { h.handle(e) } -> std::same_as<EventHandlingResult>;
+};
+
+template<typename H, typename... Ts>
+concept HandlesAll = (HasHandleFor<H, Ts> && ...);
+
+template<typename Derived, typename... T>
+    requires(IsEvent<T> && ...)
+class EventHandler {
+public:
+    EventHandler() { static_assert(HandlesAll<Derived, T...>); }
+};
+
+class EventLoop;
+
+class EventQueueBase {
+public:
+    virtual void process_events() = 0;
+
+    virtual ~EventQueueBase() = default;
+};
+
+template<typename HandlerType, typename... Ts>
+class EventQueue : public EventQueueBase {
+public:
+    EventQueue(EventLoop* loop, HandlerType* handler) : _loop(loop), _handler(handler) {};
+
+    std::optional<std::variant<Ts...>> poll();
+
+    void process_events() override {
+        while (auto event = poll()) {
+            std::visit([this](auto&& e) { _handler->handle(e); }, *event);
+        }
+    }
+
+    template<typename T>
+        requires std::disjunction_v<std::is_same<T, Ts>...>
+    void push(T&& event);
+
+private:
+    EventLoop*                     _loop;
+    HandlerType*                   _handler;
+    std::list<std::variant<Ts...>> _events;
+};
+
+class EventLoop : EventHandler<EventLoop, LoopQuitEvent>, public EventQueue<EventLoop, LoopQuitEvent> {
+public:
+    EventLoop() : EventQueue<EventLoop, LoopQuitEvent>(this, this) {}
+
+    template<typename... Ts>
+    void notify_pending(EventQueue<Ts...>* queue) {
+        std::lock_guard<std::mutex> lock(_mutex);
+        // TODO:
+        if (std::find(_events.begin(), _events.end(), queue) != _events.end()) {
+            return; // Already registered
+        }
+        _events.push_back(queue);
+        _condition.notify_all();
+    }
+
+    void run(std::function<void()> after_callback) {
+        while (_running) {
+            std::list<EventQueueBase*> new_events;
+
+            {
+                std::unique_lock<std::mutex> lock(_mutex);
+                _condition.wait(lock, [this] { return !_events.empty() || !_running; });
+                std::swap(new_events, _events);
+            }
+
+            for (auto queue: new_events) {
+                queue->process_events();
+            }
+
+            after_callback();
+        }
+    }
+
+    EventHandlingResult handle(LoopQuitEvent event) {
+        _running = false;
+        _condition.notify_all();
+        return EventHandlingResult::DONE;
+    }
+
+private:
+    std::list<EventQueueBase*> _events;
+    std::mutex                 _mutex;
+    std::condition_variable    _condition;
+    bool                       _running = true;
+};
+
+template<typename HandlerType, typename... Ts>
+std::optional<std::variant<Ts...>> EventQueue<HandlerType, Ts...>::poll() {
+    if (_events.empty()) {
+        return std::nullopt;
+    }
+
+    auto event = std::move(_events.front());
+    _events.pop_front();
+    return event;
+}
+
+template<typename HandlerType, typename... Ts>
+template<typename T>
+    requires std::disjunction_v<std::is_same<T, Ts>...>
+void EventQueue<HandlerType, Ts...>::push(T&& event) {
+    _events.emplace_back(std::forward<T>(event));
+    _loop->notify_pending(static_cast<HandlerType*>(this));
+}
+
+#endif // EVENT_HPP

Firmware/sdk/library/include_public/GridWindow.hpp

@@ -0,0 +1,128 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef GRIDWINDOW_HPP
+#define GRIDWINDOW_HPP
+#include <string>
+
+#include "Fonts.hpp"
+#include "SubSurface.hpp"
+#include "Window.hpp"
+#include "utils.hpp"
+
+template<typename SurfaceType, unsigned nWidth, unsigned nHeight>
+class GridWindow : public Window<SurfaceType> {
+public:
+    using PixelType = typename SurfaceType::PixelType;
+
+    explicit GridWindow(SurfaceType* owner) : Window<SurfaceType>(owner) {
+        for (int i = 0; i < nWidth; ++i) {
+            for (int j = 0; j < nHeight; ++j) {
+                _grid[i][j].emplace(owner);
+            }
+        }
+    }
+
+    EventHandlingResult handle_v(KeyboardEvent keyboardEvent) override {
+        if (keyboardEvent.key_code == Key::Escape) {
+            if (!_has_focus) {
+                return EventHandlingResult::CONTINUE;
+            } else {
+                auto res = _grid[_current_focus_x][_current_focus_y]->get_window()->handle(keyboardEvent);
+                if (res == EventHandlingResult::DONE) {
+                    return EventHandlingResult::DONE;
+                } else {
+                    _has_focus = false;
+                }
+            }
+        } else if (keyboardEvent.key_code == Key::Enter) {
+            if (!_has_focus) {
+                _has_focus = true;
+            } else {
+                return _grid[_current_focus_x][_current_focus_y]->get_window()->handle(keyboardEvent);
+            }
+        } else {
+            if (_has_focus) {
+                return _grid[_current_focus_x][_current_focus_y]->get_window()->handle(keyboardEvent);
+            }
+
+            if (keyboardEvent.key_code == Key::Left) {
+                if (_current_focus_x > 0) {
+                    _current_focus_x--;
+                }
+            } else if (keyboardEvent.key_code == Key::Right) {
+                if (_current_focus_x < nWidth - 1) {
+                    _current_focus_x++;
+                }
+            } else if (keyboardEvent.key_code == Key::Up) {
+                if (_current_focus_y > 0) {
+                    _current_focus_y--;
+                }
+            } else if (keyboardEvent.key_code == Key::Down) {
+                if (_current_focus_y < nHeight - 1) {
+                    _current_focus_y++;
+                }
+            }
+        }
+        refresh();
+        return EventHandlingResult::DONE;
+    }
+
+    EventHandlingResult handle_v(SurfaceResizeEvent resize) override {
+        _cell_width  = this->_owner->get_width() / nWidth;
+        _cell_height = this->_owner->get_height() / nHeight;
+        for (int i = 0; i < nWidth; ++i) {
+            for (int j = 0; j < nHeight; ++j) {
+                if constexpr (is_specialization_of<SubSurface, SurfaceType>::value) {
+                    _grid[i][j]->set_pos(this->_owner->get_x_offset() + i * _cell_width + 1,
+                                         this->_owner->get_y_offset() + j * _cell_height + 1, _cell_width - 2,
+                                         _cell_height - 2);
+                } else {
+                    _grid[i][j]->set_pos(i * _cell_width + 1, j * _cell_height + 1, _cell_width - 2, _cell_height - 2);
+                }
+            }
+        }
+        refresh();
+        return EventHandlingResult::DONE;
+    }
+
+    template<typename WindowType, typename... Args>
+    void set_window(unsigned x, unsigned y, Args&&... args) {
+        _grid[x][y]->template set_window<WindowType>(std::forward<Args>(args)...);
+    }
+
+    SubSurface<SurfaceType>& get_subsurface(unsigned x, unsigned y) {
+        // assert(x >= nWidth && y >= nHeight);
+        return *_grid[x][y];
+    }
+
+    void refresh() {
+        for (int i = 0; i < nWidth; ++i) {
+            for (int j = 0; j < nHeight; ++j) {
+                if (i == _current_focus_x && j == _current_focus_y) {
+                    this->_owner->draw_rect(i * _cell_width, j * _cell_height, _cell_width, _cell_height,
+                                            PixelType(true));
+                } else {
+                    this->_owner->draw_rect(i * _cell_width, j * _cell_height, _cell_width, _cell_height,
+                                            PixelType(false));
+                }
+            }
+        }
+    }
+
+private:
+    using SubType = std::conditional_t<is_specialization_of<SubSurface, SurfaceType>::value, SurfaceType,
+                                       SubSurface<SurfaceType>>;
+
+    std::array<std::array<std::optional<SubType>, nWidth>, nHeight> _grid;
+
+    unsigned _cell_width  = 0;
+    unsigned _cell_height = 0;
+
+    unsigned _current_focus_x = 0;
+    unsigned _current_focus_y = 0;
+    bool     _has_focus       = false;
+};
+
+#endif // TEXTWINDOW_HPP

Firmware/sdk/library/include_public/Pixel.hpp

@@ -0,0 +1,21 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef PIXEL_HPP
+#define PIXEL_HPP
+
+class Pixel {
+};
+
+struct BwPixel : public Pixel {
+    bool on = false;
+
+    BwPixel() = default;
+    BwPixel(bool on) : on(on) {}
+
+    bool operator==(const BwPixel& other) const { return on == other.on; }
+    bool operator!=(const BwPixel& other) const { return !(*this == other); }
+};
+
+#endif //PIXEL_HPP

Firmware/sdk/library/include_public/StandardEvents.hpp

@@ -0,0 +1,163 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef STANDARDEVENTS_HPP
+#define STANDARDEVENTS_HPP
+
+#include "Event.hpp"
+
+// TODO: rewrite this
+////////////////////////////////////////////////////////////
+//
+// SFML - Simple and Fast Multimedia Library
+// Copyright (C) 2007-2025 Laurent Gomila (laurent@sfml-dev.org)
+//
+// This software is provided 'as-is', without any express or implied warranty.
+// In no event will the authors be held liable for any damages arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it freely,
+// subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented;
+//    you must not claim that you wrote the original software.
+//    If you use this software in a product, an acknowledgment
+//    in the product documentation would be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such,
+//    and must not be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source distribution.
+//
+////////////////////////////////////////////////////////////
+enum class Key {
+    Unknown = -1, //!< Unhandled key
+    A       = 0,  //!< The A key
+    B,            //!< The B key
+    C,            //!< The C key
+    D,            //!< The D key
+    E,            //!< The E key
+    F,            //!< The F key
+    G,            //!< The G key
+    H,            //!< The H key
+    I,            //!< The I key
+    J,            //!< The J key
+    K,            //!< The K key
+    L,            //!< The L key
+    M,            //!< The M key
+    N,            //!< The N key
+    O,            //!< The O key
+    P,            //!< The P key
+    Q,            //!< The Q key
+    R,            //!< The R key
+    S,            //!< The S key
+    T,            //!< The T key
+    U,            //!< The U key
+    V,            //!< The V key
+    W,            //!< The W key
+    X,            //!< The X key
+    Y,            //!< The Y key
+    Z,            //!< The Z key
+    Num0,         //!< The 0 key
+    Num1,         //!< The 1 key
+    Num2,         //!< The 2 key
+    Num3,         //!< The 3 key
+    Num4,         //!< The 4 key
+    Num5,         //!< The 5 key
+    Num6,         //!< The 6 key
+    Num7,         //!< The 7 key
+    Num8,         //!< The 8 key
+    Num9,         //!< The 9 key
+    Escape,       //!< The Escape key
+    LControl,     //!< The left Control key
+    LShift,       //!< The left Shift key
+    LAlt,         //!< The left Alt key
+    LSystem,      //!< The left OS specific key: window (Windows and Linux), apple (macOS), ...
+    RControl,     //!< The right Control key
+    RShift,       //!< The right Shift key
+    RAlt,         //!< The right Alt key
+    RSystem,      //!< The right OS specific key: window (Windows and Linux), apple (macOS), ...
+    Menu,         //!< The Menu key
+    LBracket,     //!< The [ key
+    RBracket,     //!< The ] key
+    Semicolon,    //!< The ; key
+    Comma,        //!< The , key
+    Period,       //!< The . key
+    Apostrophe,   //!< The ' key
+    Slash,        //!< The / key
+    Backslash,    //!< The \ key
+    Grave,        //!< The ` key
+    Equal,        //!< The = key
+    Hyphen,       //!< The - key (hyphen)
+    Space,        //!< The Space key
+    Enter,        //!< The Enter/Return keys
+    Backspace,    //!< The Backspace key
+    Tab,          //!< The Tabulation key
+    PageUp,       //!< The Page up key
+    PageDown,     //!< The Page down key
+    End,          //!< The End key
+    Home,         //!< The Home key
+    Insert,       //!< The Insert key
+    Delete,       //!< The Delete key
+    Add,          //!< The + key
+    Subtract,     //!< The - key (minus, usually from numpad)
+    Multiply,     //!< The * key
+    Divide,       //!< The / key
+    Left,         //!< Left arrow
+    Right,        //!< Right arrow
+    Up,           //!< Up arrow
+    Down,         //!< Down arrow
+    Numpad0,      //!< The numpad 0 key
+    Numpad1,      //!< The numpad 1 key
+    Numpad2,      //!< The numpad 2 key
+    Numpad3,      //!< The numpad 3 key
+    Numpad4,      //!< The numpad 4 key
+    Numpad5,      //!< The numpad 5 key
+    Numpad6,      //!< The numpad 6 key
+    Numpad7,      //!< The numpad 7 key
+    Numpad8,      //!< The numpad 8 key
+    Numpad9,      //!< The numpad 9 key
+    F1,           //!< The F1 key
+    F2,           //!< The F2 key
+    F3,           //!< The F3 key
+    F4,           //!< The F4 key
+    F5,           //!< The F5 key
+    F6,           //!< The F6 key
+    F7,           //!< The F7 key
+    F8,           //!< The F8 key
+    F9,           //!< The F9 key
+    F10,          //!< The F10 key
+    F11,          //!< The F11 key
+    F12,          //!< The F12 key
+    F13,          //!< The F13 key
+    F14,          //!< The F14 key
+    F15,          //!< The F15 key
+    Pause,        //!< The Pause key
+};
+
+
+struct KeyboardEvent : public Event {
+    KeyboardEvent(Key key_code) : key_code(key_code) {}
+    Key key_code;
+};
+
+struct SurfaceEvent : public Event {
+    enum class EventType { CLOSED, OPENED };
+
+    EventType type;
+};
+
+struct SurfaceResizeEvent : public Event {
+    SurfaceResizeEvent(unsigned int width, unsigned int height) : width(width), height(height) {}
+    unsigned width;
+    unsigned height;
+};
+
+template<typename Derived>
+using StandardEventHandler = EventHandler<Derived, KeyboardEvent, SurfaceEvent, SurfaceResizeEvent>;
+
+template<typename Derived>
+using StandardEventQueue = EventQueue<Derived, KeyboardEvent, SurfaceEvent, SurfaceResizeEvent>;
+
+#endif // STANDARDEVENTS_HPP

Firmware/sdk/library/include_public/SubSurface.hpp

@@ -0,0 +1,58 @@
+//
+// Created by Stepan Usatiuk on 27.07.2025.
+//
+
+#ifndef SUBSURFACE_HPP
+#define SUBSURFACE_HPP
+
+#include <memory>
+#include <type_traits>
+
+#include "Pixel.hpp"
+#include "StandardEvents.hpp"
+#include "Surface.hpp"
+#include "Window.hpp"
+#include "utils.hpp"
+
+template<typename SurfaceParent>
+class SubSurface : public Surface<SubSurface<SurfaceParent>, typename SurfaceParent::PixelType> {
+public:
+    using PixelType = typename SurfaceParent::PixelType;
+
+    SubSurface(SurfaceParent* parent) : _parent(parent) {}
+    SubSurface(SubSurface<SurfaceParent>* parent) : _parent(parent->_parent) {}
+
+    void draw_pixel_impl(unsigned x, unsigned y, const PixelType& pixel) {
+        if (x >= _x_size || y >= _y_size) {
+            assert(false);
+        }
+
+        _parent->draw_pixel(x + _x_offset, y + _y_offset, pixel);
+    }
+
+    unsigned get_x_offset() const { return _x_offset; }
+
+    unsigned get_y_offset() const { return _y_offset; }
+
+    unsigned get_width_impl() const { return _x_size; }
+
+    unsigned get_height_impl() const { return _y_size; }
+
+    void set_pos(unsigned x_offset, unsigned y_offset, unsigned x_size, unsigned y_size) {
+        _x_offset = x_offset;
+        _y_offset = y_offset;
+        _x_size   = x_size;
+        _y_size   = y_size;
+        this->handle(SurfaceResizeEvent(x_size, y_size));
+    }
+
+private:
+    unsigned _x_offset = 0;
+    unsigned _y_offset = 0;
+    unsigned _x_size   = 0;
+    unsigned _y_size   = 0;
+
+    SurfaceParent* _parent;
+};
+
+#endif // SUBSURFACE_HPP

Firmware/sdk/library/include_public/Surface.hpp

@@ -0,0 +1,81 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef SURFACE_HPP
+#define SURFACE_HPP
+
+#include <cassert>
+#include <memory>
+#include <type_traits>
+
+#include "Pixel.hpp"
+#include "StandardEvents.hpp"
+#include "Window.hpp"
+#include "utils.hpp"
+
+template<typename Derived, typename PixelType>
+    requires std::is_base_of_v<Pixel, PixelType>
+class Surface : public StandardEventHandler<Derived> {
+public:
+    Surface() { static_assert(std::is_same_v<PixelType, typename Derived::PixelType>); }
+
+    void draw_pixel(unsigned x, unsigned y, const BwPixel& pixel) {
+        static_cast<Derived*>(this)->draw_pixel_impl(x, y, pixel);
+    }
+
+    void draw_rect(unsigned x, unsigned y, unsigned width, unsigned height, const BwPixel& pixel) {
+        for (unsigned i = 0; i < width; ++i) {
+            draw_pixel(x + i, y, pixel);
+            draw_pixel(x + i, y + height - 1, pixel);
+        }
+        for (unsigned i = 0; i < height; ++i) {
+            draw_pixel(x, y + i, pixel);
+            draw_pixel(x + width - 1, y + i, pixel);
+        }
+    }
+
+    void clear() {
+        for (unsigned x = 0; x < get_width(); x++) {
+            for (unsigned y = 0; y < get_height(); y++) {
+                draw_pixel(x, y, PixelType());
+            }
+        }
+    }
+
+    int get_width() const { return static_cast<const Derived*>(this)->get_width_impl(); }
+
+    int get_height() const { return static_cast<const Derived*>(this)->get_height_impl(); }
+
+    template<typename T>
+    EventHandlingResult handle(const T& event) {
+        if (_window.get())
+            return _window->handle(event);
+        return EventHandlingResult::CONTINUE;
+    }
+
+    template<typename WindowType, typename... Args>
+    void set_window(Args&&... args) {
+        _window = std::make_unique<WindowType>(static_cast<Derived*>(this), std::forward<Args>(args)...);
+    }
+
+    Surface(const Surface& other) = delete;
+
+    Surface(Surface&& other) noexcept = delete;
+
+    Surface& operator=(const Surface& other) = delete;
+
+    Surface& operator=(Surface&& other) noexcept = delete;
+
+    bool has_window() const { return _window != nullptr; }
+
+    Window<Derived>* get_window() {
+        assert(has_window());
+        return _window.get();
+    }
+
+protected:
+    std::unique_ptr<Window<Derived>> _window = nullptr;
+};
+
+#endif // SURFACE_HPP

Firmware/sdk/library/include_public/TextWindow.hpp

@@ -0,0 +1,72 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef TEXTWINDOW_HPP
+#define TEXTWINDOW_HPP
+#include <string>
+
+#include "Fonts.hpp"
+#include "Window.hpp"
+#include "utils.hpp"
+
+template<typename StringType>
+struct TextUpdateEvent : public Event {
+    TextUpdateEvent(StringType text) : new_text(std::move(text)) {}
+    StringType new_text;
+};
+
+template<typename SurfaceType, typename StringType>
+class TextWindow : public Window<SurfaceType>,
+                   public EventHandler<TextUpdateEvent<StringType>>,
+                   public EventQueue<TextWindow<SurfaceType, StringType>, TextUpdateEvent<StringType>> {
+public:
+    using PixelType = typename SurfaceType::PixelType;
+
+    explicit TextWindow(SurfaceType* owner, EventLoop* loop, StringType text = "") :
+        Window<SurfaceType>(owner), EventQueue<TextWindow, TextUpdateEvent<StringType>>(loop, this),
+        _text(std::move(text)) {}
+
+    EventHandlingResult handle_v(SurfaceResizeEvent resize) override {
+        refresh();
+        return EventHandlingResult::DONE;
+    }
+
+    EventHandlingResult handle(TextUpdateEvent<StringType> event) {
+        _text = std::move(event.new_text);
+        refresh();
+        return EventHandlingResult::DONE;
+    }
+
+    void refresh() {
+        this->_owner->clear();
+        size_t _max_col = this->_owner->get_width() / 8;
+        size_t _max_row = this->_owner->get_height() / 16;
+        int    col = 0, row = 0;
+        for (char c: _text) {
+            if (c == '\n' || col >= _max_col) {
+                row++;
+                col = 0;
+                if (c == '\n')
+                    continue;
+            }
+
+            if (row >= _max_row) {
+                break;
+            }
+
+            for (int x = 0; x < 8; x++) {
+                for (int y = 0; y < 16; y++) {
+                    bool color = fonts_Terminess_Powerline[c][y] & (1 << (8 - x));
+                    this->_owner->draw_pixel(col * 8 + x, row * 16 + y, PixelType(color));
+                }
+            }
+            col++;
+        }
+    }
+
+private:
+    StringType _text;
+};
+
+#endif // TEXTWINDOW_HPP

Firmware/sdk/library/include_public/Window.hpp

@@ -0,0 +1,40 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef WINDOW_HPP
+#define WINDOW_HPP
+
+#include <type_traits>
+
+#include "Event.hpp"
+#include "Pixel.hpp"
+#include "StandardEvents.hpp"
+#include "utils.hpp"
+
+template<typename Derived, typename PixelType>
+    requires std::is_base_of_v<Pixel, PixelType>
+class Surface;
+
+template<typename SurfaceType>
+class Window : StandardEventHandler<Window<SurfaceType>> {
+public:
+    using PixelType = typename SurfaceType::PixelType;
+
+    explicit Window(SurfaceType* owner) : _owner(owner) {
+        // static_assert(is_specialization_of<Surface, SurfaceType>::value);
+    }
+
+    virtual ~Window() = default;
+
+    EventHandlingResult handle(auto Event) { return handle_v(Event); }
+
+    virtual EventHandlingResult handle_v(KeyboardEvent) { return EventHandlingResult::CONTINUE; }
+    virtual EventHandlingResult handle_v(SurfaceEvent) { return EventHandlingResult::CONTINUE; }
+    virtual EventHandlingResult handle_v(SurfaceResizeEvent) { return EventHandlingResult::CONTINUE; }
+
+protected:
+    SurfaceType* _owner = nullptr;
+};
+
+#endif // SURFACE_HPP

Firmware/sdk/library/include_public/utils.hpp

@@ -0,0 +1,14 @@
+//
+// Created by Stepan Usatiuk on 27.07.2025.
+//
+
+#ifndef UTILS_HPP
+#define UTILS_HPP
+
+template <template <typename...> class T, typename U>
+struct is_specialization_of: std::false_type {};
+
+template <template <typename...> class T, typename... Us>
+struct is_specialization_of<T, T<Us...>>: std::true_type {};
+
+#endif //UTILS_HPP

Firmware/sdk/library/src/Event.cpp

@@ -0,0 +1,5 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#include "Event.hpp"

Firmware/sdk/library/src/TextWindow.cpp

@@ -0,0 +1,8 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#include "TextWindow.hpp"
+#include "Fonts.hpp"
+#include "Surface.hpp"
+

Firmware/sdk/library/src/Window.cpp

@@ -0,0 +1,5 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#include "Window.hpp"

Firmware/sdk/library/test/CMakeLists.txt

@@ -0,0 +1,23 @@
+include(FetchContent)
+FetchContent_Declare(
+        googletest
+        URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
+)
+# For Windows: Prevent overriding the parent project's compiler/linker settings
+set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
+FetchContent_MakeAvailable(googletest)
+
+enable_testing()
+include(GoogleTest)
+
+add_executable(
+        EventTests
+        src/EventTests.cpp
+)
+
+target_link_libraries(
+        EventTests PRIVATE
+        GTest::gtest_main cbsdk
+)
+
+gtest_discover_tests(EventTests DISCOVERY_TIMEOUT 600)

Firmware/sdk/library/test/src/EventTests.cpp

@@ -0,0 +1,44 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+
+#include <gtest/gtest.h>
+
+#include "Event.hpp"
+
+struct EventOne : public Event {
+    std::string name;
+};
+
+struct EventTwo : public Event {
+    int value;
+};
+
+template<typename Derived>
+using TestEventHandler = EventHandler<Derived, EventOne, EventTwo>;
+
+class EventHandlerTest : public TestEventHandler<EventHandlerTest> {
+public:
+    template<typename T>
+    void handle(const T& event) {
+        seen_unknown = true;
+    }
+
+    void handle(const EventOne& event) {
+        seen_event_one = true;
+    }
+
+    bool seen_event_one = false;
+    bool seen_unknown = false;
+};
+
+TEST(Event, Basic) {
+    EventHandlerTest handler;
+    EventOne event_one;
+    EventTwo event_two;
+    handler.handle(event_one);
+    ASSERT_TRUE(handler.seen_event_one);
+    handler.handle(event_two);
+    ASSERT_TRUE(handler.seen_unknown);
+}

Firmware/sdk/sfml-port/CMakeLists.txt

@@ -0,0 +1,43 @@
+cmake_minimum_required(VERSION 3.10)
+
+include(FetchContent)
+FetchContent_Declare(SFML
+        GIT_REPOSITORY https://github.com/SFML/SFML.git
+        GIT_TAG 3.0.1
+        GIT_SHALLOW ON
+        EXCLUDE_FROM_ALL
+        SYSTEM)
+FetchContent_MakeAvailable(SFML)
+
+if (CMAKE_BUILD_TYPE STREQUAL "Debug")
+#    if (NOT DEFINED SANITIZE)
+#        set(SANITIZE YES)
+#    endif ()
+endif ()
+
+if (SANITIZE STREQUAL "YES")
+    message(STATUS "Enabling sanitizers!")
+    add_compile_options(-Werror -O0 -Wall -Wextra -pedantic -Wno-unused-parameter -Wno-unused-variable
+            -Wno-error=unused-function
+            -Wshadow -Wformat=2 -Wfloat-equal -D_GLIBCXX_DEBUG -Wconversion)
+    add_compile_options(-fsanitize=address -fno-sanitize-recover)
+    add_link_options(-fsanitize=address -fno-sanitize-recover)
+endif ()
+
+if (CMAKE_BUILD_TYPE STREQUAL "Release")
+    set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE)
+endif ()
+
+if (NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
+    add_compile_options(-O3)
+    add_link_options(-O3)
+endif ()
+
+add_executable(main src/main.cpp
+        src/SfmlWindow.cpp
+        include_public/SfmlWindow.hpp)
+
+target_include_directories(main PRIVATE include)
+target_include_directories(main PUBLIC include_public)
+target_link_libraries(main PRIVATE SFML::Graphics)
+target_link_libraries(main PUBLIC cbsdk)

Firmware/sdk/sfml-port/include_public/SfmlWindow.hpp

@@ -0,0 +1,41 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#ifndef SFMLWINDOW_HPP
+#define SFMLWINDOW_HPP
+
+#include "Surface.hpp"
+#include "Window.hpp"
+
+#include <SFML/Graphics.hpp>
+
+class SfmlSurface : public Surface<SfmlSurface, BwPixel>, public StandardEventQueue<SfmlSurface> {
+public:
+    using PixelType = BwPixel;
+
+    SfmlSurface(EventLoop* loop);
+
+    ~SfmlSurface(); // override;
+
+    void draw_pixel_impl(unsigned x, unsigned y, const BwPixel& pixel);
+
+    unsigned get_width_impl() const;
+
+    unsigned get_height_impl() const;
+
+    template<typename T>
+    EventHandlingResult handle(const T& event) {
+        return _window->handle(event);
+    }
+
+    EventHandlingResult handle(SurfaceResizeEvent event);
+
+    sf::RenderWindow _sf_window;
+
+    sf::Image   _image;
+    sf::Texture _texture;
+    sf::Sprite  _sprite;
+};
+
+#endif // SFMLWINDOW_HPP

Firmware/sdk/sfml-port/src/SfmlWindow.cpp

@@ -0,0 +1,37 @@
+//
+// Created by Stepan Usatiuk on 26.07.2025.
+//
+
+#include "SfmlWindow.hpp"
+
+void SfmlSurface::draw_pixel_impl(unsigned x, unsigned y, const BwPixel& pixel) {
+    _image.setPixel({x, y}, pixel.on ? sf::Color::Black : sf::Color::White);
+}
+
+unsigned SfmlSurface::get_width_impl() const { return _image.getSize().x; }
+
+unsigned SfmlSurface::get_height_impl() const { return _image.getSize().y; }
+
+EventHandlingResult SfmlSurface::handle(SurfaceResizeEvent event) {
+    _sf_window.clear();
+    _image.resize({event.width, event.height});
+    _texture.resize({event.width, event.height});
+    _texture.update(_image);
+    _sprite = sf::Sprite(_texture);
+    sf::FloatRect view({0, 0}, {static_cast<float>(event.width), static_cast<float>(event.height)});
+    _sf_window.setView(sf::View(view));
+    return _window->handle(event);
+}
+
+SfmlSurface::SfmlSurface(EventLoop* loop) :
+    Surface<SfmlSurface, BwPixel>(),
+    EventQueue<SfmlSurface, KeyboardEvent, SurfaceEvent, SurfaceResizeEvent>(loop, this),
+    _sf_window(sf::VideoMode({640, 480}), "Test"), _image({640, 480}, sf::Color::White), _texture(_image),
+    _sprite(_texture) {
+    _sf_window.setFramerateLimit(60);
+    _sf_window.clear();
+    _sf_window.draw(_sprite);
+    _sf_window.display();
+}
+
+SfmlSurface::~SfmlSurface() {}

Firmware/sdk/sfml-port/src/main.cpp

@@ -0,0 +1,75 @@
+#include <SFML/Graphics.hpp>
+#include <barrier>
+#include <latch>
+
+#include <optional>
+#include <thread>
+
+#include "GridWindow.hpp"
+#include "SfmlWindow.hpp"
+#include "TextWindow.hpp"
+
+int main() {
+    EventLoop   loop;
+    std::latch barrier{1};
+
+    SfmlSurface* surface_ptr;
+    int         i = 0;
+    std::thread loop_thread{[&] {
+        SfmlSurface surface(&loop);
+        surface_ptr = &surface;
+
+        barrier.count_down();
+
+        surface.set_window<GridWindow<SfmlSurface, 2, 2>>();
+
+        GridWindow<SfmlSurface, 2, 2>* window =
+                static_cast<GridWindow<SfmlSurface, 2, 2>*>(surface.get_window());
+        window->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(0, 0, &loop, "hello");
+        window->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(0, 1, &loop, "hello1");
+        window->set_window<GridWindow<SubSurface<SfmlSurface>, 2, 2>>(1, 0);
+        GridWindow<SubSurface<SfmlSurface>, 2, 2>* window2 =
+                static_cast<GridWindow<SubSurface<SfmlSurface>, 2, 2>*>(
+                        window->get_subsurface(1, 0).get_window());
+        window->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(1, 1, &loop, "hello3");
+
+        window2->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(
+                0, 0, &loop, "hello2");
+        window2->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(
+                0, 1, &loop, "hello4");
+        window2->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(
+                1, 0, &loop, "hello5");
+        window2->set_window<TextWindow<SubSurface<SfmlSurface>, std::string>>(
+                1, 1, &loop, "hello6");
+        loop.run([&] {
+            surface._sf_window.clear();
+            surface._texture.update(surface._image);
+            surface._sf_window.draw(surface._sprite);
+            surface._sf_window.display();
+            static_cast<TextWindow<SubSurface<SfmlSurface>, std::string>*>(
+                    window->get_subsurface(0, 0).get_window())
+                    ->push(TextUpdateEvent<std::string>{std::string("Hello, SFML!") + std::to_string(i++)});
+        });
+    }};
+
+    barrier.wait();
+
+    while (surface_ptr->_sf_window.isOpen()) {
+        while (const std::optional event = surface_ptr->_sf_window.pollEvent()) {
+            if (event->is<sf::Event::Closed>()) {
+                surface_ptr->_sf_window.close();
+                loop.push(LoopQuitEvent{});
+            }
+            if (event->is<sf::Event::Resized>()) {
+                auto newSize = event->getIf<sf::Event::Resized>()->size;
+                surface_ptr->push(SurfaceResizeEvent{newSize.x, newSize.y});
+            }
+            if (event->is<sf::Event::KeyPressed>()) {
+                auto key = event->getIf<sf::Event::KeyPressed>();
+                surface_ptr->push(KeyboardEvent{static_cast<Key>(key->code)});
+            }
+        }
+    }
+
+    loop_thread.join();
+}