raspikeyer/settings.cpp

#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;
}