add pico_multi_booter code

Code/pico_multi_booter/sd_boot/config.h

@@ -0,0 +1,45 @@
+#ifndef CONFIG_H
+#define CONFIG_H
+
+// GPIOs for SPI interface (SD card)
+#define SD_SPI0         0
+#define SD_SCLK_PIN     18
+#define SD_MOSI_PIN     19
+#define SD_MISO_PIN     16
+#define SD_CS_PIN       17
+#define SD_DET_PIN 22
+
+#define LCD_SPI1    1
+#define LCD_SCK_PIN 10
+#define LCD_MOSI_PIN 11
+#define LCD_MISO_PIN 12
+#define LCD_CS_PIN 13
+#define LCD_DC_PIN 14
+#define LCD_RST_PIN 15
+
+// GPIOs for audio output
+#define AUDIO_LEFT     28
+#define AUDIO_RIGHT    27
+
+// GPIOs for buttons
+#define NEXT_BUTTON    2
+#define PART_BUTTON    3
+
+// Pico-internal GPIOs
+#define PICO_PS        23
+#define LED_PIN        25
+
+
+
+// PicoCalc SD Firmware Loader 
+// SD_BOOT_FLASH_OFFSET is the offset in flash memory where the bootloader starts
+// According to the applink.map ,with combined PicoMite, here is 920k
+// This offset is used to ensure that the bootloader does not get overwritten
+// when loading a new application from the SD card
+#define SD_BOOT_FLASH_OFFSET         (940 * 1024)
+
+// Maximum size of the application that can be loaded
+// This ensures we don't overwrite the bootloader itself
+#define MAX_APP_SIZE                 (PICO_FLASH_SIZE_BYTES - SD_BOOT_FLASH_OFFSET)
+
+#endif // CONFIG_H