code reorganized

src/CMakeLists.txt

@@ -0,0 +1,4 @@
+target_sources(pico_keyer PRIVATE
+    pico_keyer.cpp
+    settings.cpp
+)

src/pico_keyer.cpp

@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <pico/stdlib.h>
+
+#include "settings.h"
+
+namespace
+{
+    const uint LED_PIN = PICO_DEFAULT_LED_PIN;
+}
+
+int main()
+{
+    stdio_init_all();
+    sleep_ms(1000);
+    gpio_init(LED_PIN);
+    gpio_set_dir(LED_PIN, GPIO_OUT);
+    gpio_put(LED_PIN, 0);
+
+    Settings settings{read_settings()};
+
+    printf("Iambic mode (loaded): %d\n", static_cast<int>(settings.mode));
+    printf("WPM         (loaded): %d\n", settings.wpm);
+
+    while (true)
+    {
+        sleep_ms(1000);
+    }
+
+    return 0;
+}

src/settings.cpp

@@ -0,0 +1,71 @@
+#include <cstring>
+
+#include <pico/stdlib.h>
+
+#include "settings.h"
+
+namespace
+{
+    constexpr const uint32_t FLASH_TARGET_OFFSET = PICO_FLASH_SIZE_BYTES - FLASH_SECTOR_SIZE;
+    const uint8_t *flash_target_contents = (const uint8_t *)(XIP_BASE + FLASH_TARGET_OFFSET);
+    const uint LED_PIN = PICO_DEFAULT_LED_PIN;
+}
+
+void flash_store_callback(void *settings)
+{
+    int writeSize = (sizeof(struct Settings) / FLASH_PAGE_SIZE) + 1;
+
+    flash_range_erase(FLASH_TARGET_OFFSET, FLASH_SECTOR_SIZE);
+    flash_range_program(FLASH_TARGET_OFFSET, (uint8_t *)settings, FLASH_PAGE_SIZE);
+}
+
+void store_settings(Settings &settings)
+{
+    uint8_t *settingsAsBytes = (uint8_t *)&settings;
+
+    int result = flash_safe_execute(flash_store_callback, settingsAsBytes, 1000);
+    if (result == PICO_OK)
+    {
+        gpio_put(LED_PIN, 1);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 1);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 1);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+    }
+}
+
+Settings read_settings()
+{
+    Settings settings;
+
+    memcpy(&settings, flash_target_contents, sizeof(struct Settings));
+
+    if (settings.magic_number != MAGIC_NUMBER)
+    {
+        settings = Settings();
+
+        gpio_put(LED_PIN, 1);
+        sleep_ms(1000);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 1);
+        sleep_ms(1000);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+        gpio_put(LED_PIN, 1);
+        sleep_ms(1000);
+        gpio_put(LED_PIN, 0);
+        sleep_ms(250);
+
+        store_settings(settings);
+    }
+
+    return settings;
+}

src/settings.h

@@ -0,0 +1,26 @@
+#ifndef SETTINGS_H
+#define SETTINGS_H
+
+#include <pico/flash.h>
+
+const uint16_t MAGIC_NUMBER = 2;
+
+enum class Mode : uint8_t
+{
+    IAMBIC_A = 0,
+    IAMBIC_B,
+    // ULTIMATE
+};
+
+struct Settings
+{
+    uint16_t magic_number{MAGIC_NUMBER};   // Bytes:  2
+    Mode mode{Mode::IAMBIC_B};             // Bytes:  1
+    uint8_t wpm{20};                       // Bytes:  1
+    uint8_t dummy[FLASH_PAGE_SIZE - 4]{0}; // Sum  :  4
+};
+
+void store_settings(Settings &settings);
+Settings read_settings();
+
+#endif