StackRduino
diff --git a/‎stm/main.c‎
Lines changed: 14 additions & 8 deletions b/‎stm/main.c‎
Lines changed: 14 additions & 8 deletions
diff --git a/‎stm/sdcard.c‎
Lines changed: 6 additions & 0 deletions b/‎stm/sdcard.c‎
Lines changed: 6 additions & 0 deletions
diff --git a/‎stm/sdcard.h‎
Lines changed: 1 addition & 0 deletions b/‎stm/sdcard.h‎
Lines changed: 1 addition & 0 deletions
@@ -10,6 +10,7 @@
 #include <stm32f4xx_rtc.h>
 #include <stm32f4xx_usart.h>
 #include <stm32f4xx_rng.h>
+#include <usbd_storage_msd.h>
 #include <stm_misc.h>
 #include "std.h"
 
@@ -815,14 +816,6 @@ int main(void) {
         flash_error(4);
     }
 
-#ifdef USE_HOST_MODE
-    // USB host
-    pyb_usb_host_init();
-#elif defined(USE_DEVICE_MODE)
-    // USB device
-    pyb_usb_dev_init();
-#endif
-
     if (first_soft_reset) {
 #if MICROPY_HW_HAS_MMA7660
         // MMA: init and reset address to zero
@@ -839,10 +832,23 @@ int main(void) {
         FRESULT res = f_mount(&fatfs1, "1:", 1);
         if (res != FR_OK) {
             printf("[SD] could not mount SD card\n");
+        } else {
+            if (first_soft_reset) {
+                // use SD card as medium for the USB MSD
+                usbd_storage_select_medium(USBD_STORAGE_MEDIUM_SDCARD);
+            }
         }
     }
 #endif
 
+#ifdef USE_HOST_MODE
+    // USB host
+    pyb_usb_host_init();
+#elif defined(USE_DEVICE_MODE)
+    // USB device
+    pyb_usb_dev_init();
+#endif
+
     // run main script
     {
         vstr_t *vstr = vstr_new();
 
@@ -95,6 +95,12 @@ void sdcard_power_off(void) {
     SD_DeInit();
 }
 
+uint64_t sdcard_get_capacity_in_bytes(void) {
+    SD_CardInfo SDCardInfo;
+    SD_GetCardInfo(&SDCardInfo);
+    return SDCardInfo.CardCapacity;
+}
+
 bool sdcard_read_block(uint8_t *dest, uint32_t block_num) {
     // TODO return error if not powered on
 
 
@@ -5,6 +5,7 @@ void sdcard_init(void);
 bool sdcard_is_present(void);
 bool sdcard_power_on(void);
 void sdcard_power_off(void);
+uint64_t sdcard_get_capacity_in_bytes(void);
 bool sdcard_read_block(uint8_t *dest, uint32_t block_num);
 bool sdcard_write_block(const uint8_t *src, uint32_t block_num);