adding inital example

Author: hathach

examples/MassStorage/msc_esp32_file_browser/.none.test.only

@@ -0,0 +1,169 @@
+/*********************************************************************
+ Adafruit invests time and resources providing this open source code,
+ please support Adafruit and open-source hardware by purchasing
+ products from Adafruit!
+
+ MIT license, check LICENSE for more information
+ Copyright (c) 2019 Ha Thach for Adafruit Industries
+ All text above, and the splash screen below must be included in
+ any redistribution
+*********************************************************************/
+
+/* This example demo how to expose on-board external Flash as USB Mass Storage.
+ * Following library is required
+ *   - Adafruit_SPIFlash https://github.com/adafruit/Adafruit_SPIFlash
+ *   - SdFat https://github.com/adafruit/SdFat
+ *
+ * Note: Adafruit fork of SdFat enabled ENABLE_EXTENDED_TRANSFER_CLASS and FAT12_SUPPORT
+ * in SdFatConfig.h, which is needed to run SdFat on external flash. You can use original
+ * SdFat library and manually change those macros
+ */
+
+#include "SPI.h"
+#include "SdFat.h"
+#include "Adafruit_SPIFlash.h"
+#include "Adafruit_TinyUSB.h"
+
+// ESP32 use same flash device that store code.
+// Therefore there is no need to specify the SPI and SS
+Adafruit_FlashTransport_ESP32 flashTransport;
+Adafruit_SPIFlash flash(&flashTransport);
+
+// file system object from SdFat
+FatFileSystem fatfs;
+
+FatFile root;
+FatFile file;
+
+// USB Mass Storage object
+Adafruit_USBD_MSC usb_msc;
+
+// Check if flash is formatted
+bool formatted;
+
+// Set to true when PC write to flash
+bool changed;
+
+// the setup function runs once when you press reset or power the board
+void setup()
+{
+  pinMode(LED_BUILTIN, OUTPUT);
+  Serial.begin(115200);
+
+  flash.begin();
+
+  // Set disk vendor id, product id and revision with string up to 8, 16, 4 characters respectively
+  usb_msc.setID("Adafruit", "External Flash", "1.0");
+
+  // Set callback
+  usb_msc.setReadWriteCallback(msc_read_cb, msc_write_cb, msc_flush_cb);
+
+  // Set disk size, block size should be 512 regardless of spi flash page size
+  usb_msc.setCapacity(flash.size()/512, 512);
+
+  // MSC is ready for read/write
+  usb_msc.setUnitReady(true);
+
+  usb_msc.begin();
+
+  // Init file system on the flash
+  formatted = fatfs.begin(&flash);
+
+//  while ( !Serial ) delay(10);   // wait for native usb
+  if ( !formatted )
+  {
+    Serial.println("Failed to init files system, flash may not be formatted");
+  }
+
+  Serial.println("Adafruit TinyUSB Mass Storage External Flash example");
+  Serial.print("JEDEC ID: 0x"); Serial.println(flash.getJEDECID(), HEX);
+  Serial.print("Flash size: "); Serial.print(flash.size() / 1024); Serial.println(" KB");
+
+  changed = true; // to print contents initially
+}
+
+void loop()
+{
+  if ( changed )
+  {
+    changed = false;
+
+    // check if host formatted disk
+    if (!formatted)
+    {
+      formatted = fatfs.begin(&flash);
+    }
+
+    // skip if still not formatted
+    if (!formatted) return;
+
+    Serial.println("Opening root");
+
+    if ( !root.open("/") )
+    {
+      Serial.println("open root failed");
+      return;
+    }
+
+    Serial.println("Flash contents:");
+
+    // Open next file in root.
+    // Warning, openNext starts at the current directory position
+    // so a rewind of the directory may be required.
+    while ( file.openNext(&root, O_RDONLY) )
+    {
+      file.printFileSize(&Serial);
+      Serial.write(' ');
+      file.printName(&Serial);
+      if ( file.isDir() )
+      {
+        // Indicate a directory.
+        Serial.write('/');
+      }
+      Serial.println();
+      file.close();
+    }
+
+    root.close();
+
+    Serial.println();
+    delay(1000);
+  }
+}
+
+// Callback invoked when received READ10 command.
+// Copy disk's data to buffer (up to bufsize) and 
+// return number of copied bytes (must be multiple of block size) 
+int32_t msc_read_cb (uint32_t lba, void* buffer, uint32_t bufsize)
+{
+  // Note: SPIFLash Bock API: readBlocks/writeBlocks/syncBlocks
+  // already include 4K sector caching internally. We don't need to cache it, yahhhh!!
+  return flash.readBlocks(lba, (uint8_t*) buffer, bufsize/512) ? bufsize : -1;
+}
+
+// Callback invoked when received WRITE10 command.
+// Process data in buffer to disk's storage and 
+// return number of written bytes (must be multiple of block size)
+int32_t msc_write_cb (uint32_t lba, uint8_t* buffer, uint32_t bufsize)
+{
+  digitalWrite(LED_BUILTIN, HIGH);
+
+  // Note: SPIFLash Bock API: readBlocks/writeBlocks/syncBlocks
+  // already include 4K sector caching internally. We don't need to cache it, yahhhh!!
+  return flash.writeBlocks(lba, buffer, bufsize/512) ? bufsize : -1;
+}
+
+// Callback invoked when WRITE10 command is completed (status received and accepted by host).
+// used to flush any pending cache.
+void msc_flush_cb (void)
+{
+  // sync with flash
+  flash.syncBlocks();
+
+  // clear file system's cache to force refresh
+  fatfs.cacheClear();
+
+  changed = true;
+
+  digitalWrite(LED_BUILTIN, LOW);
+}