diff --git a/ports/atmel-samd/Makefile b/ports/atmel-samd/Makefile
index 041f1d1ad7..a5d1fd7c0e 100644
--- a/ports/atmel-samd/Makefile
+++ b/ports/atmel-samd/Makefile
@@ -252,7 +252,10 @@ ifeq ($(INTERNAL_FLASH_FILESYSTEM),1)
 SRC_C += internal_flash.c
 endif
 ifeq ($(SPI_FLASH_FILESYSTEM),1)
-SRC_C += spi_flash.c
+SRC_C += external_flash/external_flash.c external_flash/spi_flash.c
+endif
+ifeq ($(QSPI_FLASH_FILESYSTEM),1)
+SRC_C += external_flash/external_flash.c external_flash/qspi_flash.c
 endif
 
 SRC_COMMON_HAL = \
diff --git a/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h b/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
index fdb96c06c3..cc09d7f790 100644
--- a/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
@@ -38,7 +38,7 @@
 
 #define SPEAKER_ENABLE_PIN    (&pin_PA30)
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -47,8 +47,8 @@
 
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_S25FL216K.h"
-#include "flash_GD25Q16C.h"
+#include "external_flash/devices/S25FL216K.h"
+#include "external_flash/devices/GD25Q16C.h"
 
 #define CALIBRATE_CRYSTALLESS 1
 
diff --git a/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
index 448c6c52bf..378b0891ad 100644
--- a/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
@@ -31,7 +31,7 @@
 #define MICROPY_PORT_B        ( 0 )
 #define MICROPY_PORT_C        ( 0 )
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -40,5 +40,5 @@
 
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_S25FL216K.h"
-#include "flash_GD25Q16C.h"
+#include "external_flash/devices/S25FL216K.h"
+#include "external_flash/devices/GD25Q16C.h"
diff --git a/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
index 02ce5e1cdc..b5ed682962 100644
--- a/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
@@ -33,7 +33,7 @@
 #define MICROPY_PORT_B        ( 0 )
 #define MICROPY_PORT_C        ( 0 )
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -42,4 +42,4 @@
 
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_S25FL064L.h"
+#include "external_flash/devices/S25FL064L.h"
diff --git a/ports/atmel-samd/boards/itsybitsy_m0/mpconfigboard.h b/ports/atmel-samd/boards/itsybitsy_m0/mpconfigboard.h
index f41059ee4f..15a9922211 100644
--- a/ports/atmel-samd/boards/itsybitsy_m0/mpconfigboard.h
+++ b/ports/atmel-samd/boards/itsybitsy_m0/mpconfigboard.h
@@ -33,7 +33,7 @@
 #define MICROPY_PORT_B        (PORT_PB22 | PORT_PB23 | PORT_PB03 )
 #define MICROPY_PORT_C        (0)
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -41,6 +41,6 @@
 #define CIRCUITPY_INTERNAL_NVM_SIZE 0
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-//#include "flash_S25FL216K.h"
-#include "flash_W25Q80DV.h"
-//#include "flash_GD25Q16C.h"
+//#include "external_flash/devices/S25FL216K.h"
+#include "external_flash/devices/W25Q80DV.h"
+//#include "external_flash/devices/GD25Q16C.h"
diff --git a/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h b/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
index 023beb6883..70e830620d 100644
--- a/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
@@ -34,7 +34,7 @@
 #define MICROPY_PORT_B        (PORT_PB03 | PORT_PB22 | PORT_PB23)
 #define MICROPY_PORT_C        (0)
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -43,5 +43,5 @@
 
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_S25FL216K.h"
-#include "flash_GD25Q16C.h"
+#include "external_flash/devices/S25FL216K.h"
+#include "external_flash/devices/GD25Q16C.h"
diff --git a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
index 1af18ecbc2..b8f14e6253 100644
--- a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
@@ -33,14 +33,14 @@
 #define SPI_FLASH_DIPO              3   // same as MISO pad
 
 // These are pins not to reset.
-#define MICROPY_PORT_A        (PORT_PA27)
-#define MICROPY_PORT_B        (PORT_PB06 | PORT_PB08 | PORT_PB09 | PORT_PB10 | PORT_PB11 | PORT_PB17)
+#define MICROPY_PORT_A        (PORT_PA08 | PORT_PA09 | PORT_PA10 | PORT_PA11 | PORT_PA27)
+#define MICROPY_PORT_B        (PORT_PB10 | PORT_PB11 | PORT_PB17)
 #define MICROPY_PORT_C        (0)
 #define MICROPY_PORT_D        (0)
 
 #define AUTORESET_DELAY_MS 500
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code
@@ -49,5 +49,5 @@
 
 #define BOARD_FLASH_SIZE (FLASH_SIZE - 0x4000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_S25FL216K.h"
-#include "flash_GD25Q16C.h"
+#include "external_flash/devices/S25FL216K.h"
+#include "external_flash/devices/GD25Q16C.h"
diff --git a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.mk b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.mk
index 0f96532396..1d59ed9664 100644
--- a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.mk
+++ b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.mk
@@ -4,7 +4,7 @@ USB_PID = 0x8021
 USB_PRODUCT = "Metro M4 Express"
 USB_MANUFACTURER = "Adafruit Industries LLC"
 
-SPI_FLASH_FILESYSTEM = 1
+QSPI_FLASH_FILESYSTEM = 1
 
 CHIP_VARIANT = SAMD51J19A
 CHIP_FAMILY = samd51
diff --git a/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h b/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
index 2a5792a63b..62bca9a413 100644
--- a/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
+++ b/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
@@ -40,7 +40,7 @@
 
 #define CALIBRATE_CRYSTALLESS 1
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -48,5 +48,4 @@
 #define CIRCUITPY_INTERNAL_NVM_SIZE 0
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-#include "flash_W25Q32BV.h"
-
+#include "external_flash/devices/W25Q32BV.h"
diff --git a/ports/atmel-samd/boards/ugame10/mpconfigboard.h b/ports/atmel-samd/boards/ugame10/mpconfigboard.h
index 16a792f421..d0d9296a40 100644
--- a/ports/atmel-samd/boards/ugame10/mpconfigboard.h
+++ b/ports/atmel-samd/boards/ugame10/mpconfigboard.h
@@ -33,7 +33,7 @@
 
 #define CALIBRATE_CRYSTALLESS 1
 
-#include "spi_flash.h"
+#include "external_flash/external_flash.h"
 
 // If you change this, then make sure to update the linker scripts as well to
 // make sure you don't overwrite code.
@@ -41,5 +41,5 @@
 #define CIRCUITPY_INTERNAL_NVM_SIZE 0
 #define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
 
-//#include "flash_W25Q32BV.h"
-#include "flash_S25FL216K.h"
+//#include "external_flash/devices/W25Q32BV.h"
+#include "external_flash/devices/S25FL216K.h"
diff --git a/ports/atmel-samd/external_flash/common_commands.h b/ports/atmel-samd/external_flash/common_commands.h
new file mode 100644
index 0000000000..fc05e70de7
--- /dev/null
+++ b/ports/atmel-samd/external_flash/common_commands.h
@@ -0,0 +1,41 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_COMMON_COMMANDS_H
+#define MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_COMMON_COMMANDS_H
+
+#define CMD_READ_JEDEC_ID 0x9f
+#define CMD_READ_DATA 0x03
+#define CMD_SECTOR_ERASE 0x20
+// #define CMD_SECTOR_ERASE CMD_READ_JEDEC_ID
+#define CMD_DISABLE_WRITE 0x04
+#define CMD_ENABLE_WRITE 0x06
+#define CMD_PAGE_PROGRAM 0x02
+// #define CMD_PAGE_PROGRAM CMD_READ_JEDEC_ID
+#define CMD_READ_STATUS 0x05
+#define CMD_WRITE_STATUS_BYTE1 0x01
+#define CMD_QUAD_READ 0x6b
+
+#endif  // MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_COMMON_COMMANDS_H
diff --git a/ports/atmel-samd/boards/flash_AT25DF081A.h b/ports/atmel-samd/external_flash/devices/AT25DF081A.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_AT25DF081A.h
rename to ports/atmel-samd/external_flash/devices/AT25DF081A.h
diff --git a/ports/atmel-samd/boards/flash_GD25Q16C.h b/ports/atmel-samd/external_flash/devices/GD25Q16C.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_GD25Q16C.h
rename to ports/atmel-samd/external_flash/devices/GD25Q16C.h
diff --git a/ports/atmel-samd/boards/flash_S25FL064L.h b/ports/atmel-samd/external_flash/devices/S25FL064L.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_S25FL064L.h
rename to ports/atmel-samd/external_flash/devices/S25FL064L.h
diff --git a/ports/atmel-samd/external_flash/devices/S25FL116K.h b/ports/atmel-samd/external_flash/devices/S25FL116K.h
new file mode 100644
index 0000000000..4928bd04e2
--- /dev/null
+++ b/ports/atmel-samd/external_flash/devices/S25FL116K.h
@@ -0,0 +1,54 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_ATMEL_SAMD_BOARD_FLASH_S25FL116K_H
+#define MICROPY_INCLUDED_ATMEL_SAMD_BOARD_FLASH_S25FL116K_H
+
+// Settings for the Cypress (was Spansion) S25FL116K 2MiB SPI flash.
+// Datasheet: http://www.cypress.com/file/196886/download
+
+// The total flash size in bytes.
+#define SPI_FLASH_TOTAL_SIZE  (1 << 21) // 2 MiB
+
+// The size of the smallest erase unit thats erased with command 0x20.
+#define SPI_FLASH_ERASE_SIZE  (1 << 12) // 4 KiB
+
+// The size of a page that is programmed with page program command 0x02.
+#define SPI_FLASH_PAGE_SIZE   (256)     // 256 bytes
+
+// These are the first three response bytes to the JEDEC ID command 0x9f that is
+// used to confirm we're talking to the flash we expect.
+#ifndef SPI_FLASH_JEDEC_MANUFACTURER
+#define SPI_FLASH_JEDEC_MANUFACTURER 0x01
+#define SPI_FLASH_SECTOR_PROTECTION false
+#else
+#define SPI_FLASH_JEDEC_MANUFACTURER_2 0x01
+#define SPI_FLASH_SECTOR_PROTECTION_2 false
+#endif
+#define SPI_FLASH_JEDEC_MEMORY_TYPE  0x40
+#define SPI_FLASH_JEDEC_CAPACITY     0x15
+
+#endif  // MICROPY_INCLUDED_ATMEL_SAMD_BOARD_FLASH_S25FL216K_H
diff --git a/ports/atmel-samd/boards/flash_S25FL216K.h b/ports/atmel-samd/external_flash/devices/S25FL216K.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_S25FL216K.h
rename to ports/atmel-samd/external_flash/devices/S25FL216K.h
diff --git a/ports/atmel-samd/boards/flash_W25Q32BV.h b/ports/atmel-samd/external_flash/devices/W25Q32BV.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_W25Q32BV.h
rename to ports/atmel-samd/external_flash/devices/W25Q32BV.h
diff --git a/ports/atmel-samd/boards/flash_W25Q80DV.h b/ports/atmel-samd/external_flash/devices/W25Q80DV.h
similarity index 100%
rename from ports/atmel-samd/boards/flash_W25Q80DV.h
rename to ports/atmel-samd/external_flash/devices/W25Q80DV.h
diff --git a/ports/atmel-samd/spi_flash.c b/ports/atmel-samd/external_flash/external_flash.c
similarity index 66%
rename from ports/atmel-samd/spi_flash.c
rename to ports/atmel-samd/external_flash/external_flash.c
index 55a00dcba3..d3a2b4bae6 100644
--- a/ports/atmel-samd/spi_flash.c
+++ b/ports/atmel-samd/external_flash/external_flash.c
@@ -23,11 +23,13 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#include "spi_flash.h"
+#include "external_flash.h"
 
 #include <stdint.h>
 #include <string.h>
 
+#include "external_flash/spi_flash_api.h"
+#include "external_flash/common_commands.h"
 #include "extmod/vfs.h"
 #include "extmod/vfs_fat.h"
 #include "py/misc.h"
@@ -46,17 +48,6 @@
 
 #define NO_SECTOR_LOADED 0xFFFFFFFF
 
-#define CMD_READ_JEDEC_ID 0x9f
-#define CMD_READ_DATA 0x03
-#define CMD_SECTOR_ERASE 0x20
-// #define CMD_SECTOR_ERASE CMD_READ_JEDEC_ID
-#define CMD_DISABLE_WRITE 0x04
-#define CMD_ENABLE_WRITE 0x06
-#define CMD_PAGE_PROGRAM 0x02
-// #define CMD_PAGE_PROGRAM CMD_READ_JEDEC_ID
-#define CMD_READ_STATUS 0x05
-#define CMD_WRITE_STATUS_BYTE1 0x01
-
 static bool spi_flash_is_initialised = false;
 
 struct spi_m_sync_descriptor spi_flash_desc;
@@ -71,46 +62,20 @@ static uint32_t dirty_mask;
 // Address of the scratch flash sector.
 #define SCRATCH_SECTOR (SPI_FLASH_TOTAL_SIZE - SPI_FLASH_ERASE_SIZE)
 
-// Enable the flash over SPI.
-static void flash_enable(void) {
-    gpio_set_pin_level(SPI_FLASH_CS_PIN, false);
-}
-
-// Disable the flash over SPI.
-static void flash_disable(void) {
-    gpio_set_pin_level(SPI_FLASH_CS_PIN, true);
-}
-
 // Wait until both the write enable and write in progress bits have cleared.
 static bool wait_for_flash_ready(void) {
-    uint8_t read_status_request[2] = {CMD_READ_STATUS, 0x00};
-    uint8_t read_status_response[2] = {0x00, 0x00};
-    struct spi_xfer read_status_xfer = {read_status_request, read_status_response, 2};
-    int32_t status;
+    uint8_t read_status_response[1] = {0x00};
+    bool ok = true;
     // Both the write enable and write in progress bits should be low.
     do {
-        flash_enable();
-        status = spi_m_sync_transfer(&spi_flash_desc, &read_status_xfer);
-        flash_disable();
-    } while (status >= 0 && (read_status_response[1] & 0x3) != 0);
-    return status >= 0;         // status is number of chars read or a negative error code.
+        ok = spi_flash_read_command(CMD_READ_STATUS, read_status_response, 1);
+    } while (ok && (read_status_response[0] & 0x3) != 0);
+    return ok;
 }
 
 // Turn on the write enable bit so we can program and erase the flash.
 static bool write_enable(void) {
-    flash_enable();
-    uint8_t enable_write_request[1] = {CMD_ENABLE_WRITE};
-    struct spi_xfer enable_write_xfer = {enable_write_request, 0, 1};
-    int32_t status = spi_m_sync_transfer(&spi_flash_desc, &enable_write_xfer);
-    flash_disable();
-    return status >= 0;         // status is number of chars read or a negative error code.
-}
-
-// Pack the low 24 bits of the address into a uint8_t array.
-static void address_to_bytes(uint32_t address, uint8_t* bytes) {
-    bytes[0] = (address >> 16) & 0xff;
-    bytes[1] = (address >> 8) & 0xff;
-    bytes[2] = address & 0xff;
+    return spi_flash_command(CMD_ENABLE_WRITE);
 }
 
 // Read data_length's worth of bytes starting at address into data.
@@ -121,19 +86,7 @@ static bool read_flash(uint32_t address, uint8_t* data, uint32_t data_length) {
     if (!wait_for_flash_ready()) {
         return false;
     }
-    // We can read as much as we want sequentially.
-    uint8_t read_data_request[4] = {CMD_READ_DATA, 0x00, 0x00, 0x00};
-    struct spi_xfer read_data_xfer = {read_data_request, 0, 4};
-    // Write the SPI flash read address into the bytes following the command byte.
-    address_to_bytes(address, read_data_request + 1);
-    flash_enable();
-    int32_t status = spi_m_sync_transfer(&spi_flash_desc, &read_data_xfer);
-    struct spi_xfer read_data_buffer_xfer = {0, data, data_length};
-    if (status >= 0) {
-        status = spi_m_sync_transfer(&spi_flash_desc, &read_data_buffer_xfer);
-    }
-    flash_disable();
-    return status >= 0;
+    return spi_flash_read_data(address, data, data_length);
 }
 
 // Writes data_length's worth of bytes starting at address from data. Assumes
@@ -162,29 +115,9 @@ static bool write_flash(uint32_t address, const uint8_t* data, uint32_t data_len
         if (!wait_for_flash_ready() || !write_enable()) {
             return false;
         }
-        int32_t status;
 
-        #ifdef SPI_FLASH_SECTOR_PROTECTION
-        // Print out the protection status.
-        // uint8_t protect_check[5] = {0x3C, 0x00, 0x00, 0x00, 0x00};
-        // address_to_bytes(address + bytes_written, protect_check + 1);
-        // flash_enable();
-        // status = spi_write_buffer_wait(&spi_flash_desc, protect_check, 5);
-        // flash_disable();
-        #endif
-
-        flash_enable();
-        uint8_t page_program_request[4] = {CMD_PAGE_PROGRAM, 0x00, 0x00, 0x00};
-        // Write the SPI flash write address into the bytes following the command byte.
-        address_to_bytes(address + bytes_written, page_program_request + 1);
-        struct spi_xfer page_program_xfer = {page_program_request, 0, 4};
-        status = spi_m_sync_transfer(&spi_flash_desc, &page_program_xfer);
-        if (status >= 0) {
-            struct spi_xfer write_data_buffer_xfer = {(uint8_t*) data + bytes_written, 0, SPI_FLASH_PAGE_SIZE};
-            status = spi_m_sync_transfer(&spi_flash_desc, &write_data_buffer_xfer);
-        }
-        flash_disable();
-        if (status < 0) {
+        if (!spi_flash_write_data(address + bytes_written, (uint8_t*) data + bytes_written,
+                                  SPI_FLASH_PAGE_SIZE)) {
             return false;
         }
     }
@@ -228,13 +161,8 @@ static bool erase_sector(uint32_t sector_address) {
         return false;
     }
 
-    uint8_t erase_request[4] = {CMD_SECTOR_ERASE, 0x00, 0x00, 0x00};
-    address_to_bytes(sector_address, erase_request + 1);
-    struct spi_xfer erase_xfer = {erase_request, 0, 4};
-    flash_enable();
-    int32_t status = spi_m_sync_transfer(&spi_flash_desc, &erase_xfer);
-    flash_disable();
-    return status >= 0;
+    spi_flash_sector_command(CMD_SECTOR_ERASE, sector_address);
+    return true;
 }
 
 // Sector is really 24 bits.
@@ -252,45 +180,12 @@ static bool copy_block(uint32_t src_address, uint32_t dest_address) {
     return true;
 }
 
-void spi_flash_init(void) {
+void external_flash_init(void) {
     if (spi_flash_is_initialised) {
         return;
     }
 
-    samd_peripherals_sercom_clock_init(SPI_FLASH_SERCOM, SPI_FLASH_SERCOM_INDEX);
-
-    // Set up with defaults, then change.
-    spi_m_sync_init(&spi_flash_desc, SPI_FLASH_SERCOM);
-
-    hri_sercomspi_write_CTRLA_DOPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DOPO);
-    hri_sercomspi_write_CTRLA_DIPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DIPO);
-
-    gpio_set_pin_direction(SPI_FLASH_SCK_PIN, GPIO_DIRECTION_OUT);
-    gpio_set_pin_pull_mode(SPI_FLASH_SCK_PIN, GPIO_PULL_OFF);
-    gpio_set_pin_function(SPI_FLASH_SCK_PIN, SPI_FLASH_SCK_PIN_FUNCTION);
-
-    gpio_set_pin_direction(SPI_FLASH_MOSI_PIN, GPIO_DIRECTION_OUT);
-    gpio_set_pin_pull_mode(SPI_FLASH_MOSI_PIN, GPIO_PULL_OFF);
-    gpio_set_pin_function(SPI_FLASH_MOSI_PIN, SPI_FLASH_MOSI_PIN_FUNCTION);
-
-    gpio_set_pin_direction(SPI_FLASH_MISO_PIN, GPIO_DIRECTION_IN);
-    gpio_set_pin_pull_mode(SPI_FLASH_MISO_PIN, GPIO_PULL_OFF);
-    gpio_set_pin_function(SPI_FLASH_MISO_PIN, SPI_FLASH_MISO_PIN_FUNCTION);
-
-    hri_sercomspi_write_CTRLA_DOPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DOPO);
-    hri_sercomspi_write_CTRLA_DIPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DIPO);
-
-    spi_m_sync_set_baudrate(&spi_flash_desc, samd_peripherals_spi_baudrate_to_baud_reg_value(SPI_FLASH_BAUDRATE));
-
-    gpio_set_pin_direction(SPI_FLASH_CS_PIN, GPIO_DIRECTION_OUT);
-    // There's already a pull-up on the board.
-    gpio_set_pin_pull_mode(SPI_FLASH_CS_PIN, GPIO_PULL_OFF);
-    gpio_set_pin_function(SPI_FLASH_CS_PIN, GPIO_PIN_FUNCTION_OFF);
-
-    // Set CS high (disabled).
-    flash_disable();
-
-    spi_m_sync_enable(&spi_flash_desc);
+    spi_flash_init();
 
     // Activity LED for flash writes.
 #ifdef MICROPY_HW_LED_MSC
@@ -300,20 +195,17 @@ void spi_flash_init(void) {
     gpio_set_pin_level(MICROPY_HW_LED_MSC, false);
 #endif
 
-    uint8_t jedec_id_request[4] = {CMD_READ_JEDEC_ID, 0x00, 0x00, 0x00};
-    uint8_t jedec_id_response[4] = {0x00, 0x00, 0x00, 0x00};
-    struct spi_xfer jedec_id_xfer = { jedec_id_request, jedec_id_response, 4 };
-    flash_enable();
-    spi_m_sync_transfer(&spi_flash_desc, &jedec_id_xfer);
-    flash_disable();
-    uint8_t manufacturer = jedec_id_response[1];
-    if ((jedec_id_response[1] == SPI_FLASH_JEDEC_MANUFACTURER
+    uint8_t jedec_id_response[3] = {0x00, 0x00, 0x00};
+    spi_flash_read_command(CMD_READ_JEDEC_ID, jedec_id_response, 3);
+
+    uint8_t manufacturer = jedec_id_response[0];
+    if ((jedec_id_response[0] == SPI_FLASH_JEDEC_MANUFACTURER
 #ifdef SPI_FLASH_JEDEC_MANUFACTURER_2
-         || jedec_id_response[1] == SPI_FLASH_JEDEC_MANUFACTURER_2
+         || jedec_id_response[0] == SPI_FLASH_JEDEC_MANUFACTURER_2
 #endif
          ) &&
-        jedec_id_response[2] == SPI_FLASH_JEDEC_MEMORY_TYPE &&
-        jedec_id_response[3] == SPI_FLASH_JEDEC_CAPACITY) {
+        jedec_id_response[1] == SPI_FLASH_JEDEC_MEMORY_TYPE &&
+        jedec_id_response[2] == SPI_FLASH_JEDEC_CAPACITY) {
         spi_flash_is_initialised = true;
     } else {
         // Unknown flash chip!
@@ -329,19 +221,12 @@ void spi_flash_init(void) {
         write_enable();
 
         // Turn off sector protection
-        uint8_t disable_protect_request[2] = {CMD_WRITE_STATUS_BYTE1, 0x00};
-        struct spi_xfer disable_protect_xfer = { disable_protect_request, 0, 4 };
-        flash_enable();
-        spi_m_sync_transfer(&spi_flash_desc, &disable_protect_xfer);
-        flash_disable();
+        uint8_t data[1] = {0x00};
+        spi_flash_write_command(CMD_WRITE_STATUS_BYTE1, data, 1);
     }
 
     // Turn off writes in case this is a microcontroller only reset.
-    uint8_t disable_write_request[1] = {CMD_DISABLE_WRITE};
-    struct spi_xfer disable_write_xfer = { disable_write_request, 0, 1 };
-    flash_enable();
-    spi_m_sync_transfer(&spi_flash_desc, &disable_write_xfer);
-    flash_disable();
+    spi_flash_command(CMD_DISABLE_WRITE);
 
     wait_for_flash_ready();
 
@@ -353,12 +238,12 @@ void spi_flash_init(void) {
 }
 
 // The size of each individual block.
-uint32_t spi_flash_get_block_size(void) {
+uint32_t external_flash_get_block_size(void) {
     return FILESYSTEM_BLOCK_SIZE;
 }
 
 // The total number of available blocks.
-uint32_t spi_flash_get_block_count(void) {
+uint32_t external_flash_get_block_count(void) {
     // We subtract one erase sector size because we may use it as a staging area
     // for writes.
     return SPI_FLASH_PART1_START_BLOCK + (SPI_FLASH_TOTAL_SIZE - SPI_FLASH_ERASE_SIZE) / FILESYSTEM_BLOCK_SIZE;
@@ -510,12 +395,12 @@ static void spi_flash_flush_keep_cache(bool keep_cache) {
 
 // External flash function used. If called externally we assume we won't need
 // the cache after.
-void spi_flash_flush(void) {
+void external_flash_flush(void) {
     spi_flash_flush_keep_cache(false);
 }
 
 void flash_flush(void) {
-    spi_flash_flush();
+    external_flash_flush();
 }
 
 // Builds a partition entry for the MBR.
@@ -557,7 +442,7 @@ static void build_partition(uint8_t *buf, int boot, int type,
 }
 
 static int32_t convert_block_to_flash_addr(uint32_t block) {
-    if (SPI_FLASH_PART1_START_BLOCK <= block && block < spi_flash_get_block_count()) {
+    if (SPI_FLASH_PART1_START_BLOCK <= block && block < external_flash_get_block_count()) {
         // a block in partition 1
         block -= SPI_FLASH_PART1_START_BLOCK;
         return block * FILESYSTEM_BLOCK_SIZE;
@@ -566,7 +451,7 @@ static int32_t convert_block_to_flash_addr(uint32_t block) {
     return -1;
 }
 
-bool spi_flash_read_block(uint8_t *dest, uint32_t block) {
+bool external_flash_read_block(uint8_t *dest, uint32_t block) {
     if (block == 0) {
         // Fake the MBR so we can decide on our own partition table
         for (int i = 0; i < 446; i++) {
@@ -575,7 +460,7 @@ bool spi_flash_read_block(uint8_t *dest, uint32_t block) {
 
         build_partition(dest + 446, 0, 0x01 /* FAT12 */,
                         SPI_FLASH_PART1_START_BLOCK,
-                        spi_flash_get_block_count() - SPI_FLASH_PART1_START_BLOCK);
+                        external_flash_get_block_count() - SPI_FLASH_PART1_START_BLOCK);
         build_partition(dest + 462, 0, 0, 0, 0);
         build_partition(dest + 478, 0, 0, 0, 0);
         build_partition(dest + 494, 0, 0, 0, 0);
@@ -618,7 +503,7 @@ bool spi_flash_read_block(uint8_t *dest, uint32_t block) {
     }
 }
 
-bool spi_flash_write_block(const uint8_t *data, uint32_t block) {
+bool external_flash_write_block(const uint8_t *data, uint32_t block) {
     if (block < SPI_FLASH_PART1_START_BLOCK) {
         // Fake writing below the flash partition.
         return true;
@@ -670,18 +555,18 @@ bool spi_flash_write_block(const uint8_t *data, uint32_t block) {
     }
 }
 
-mp_uint_t spi_flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_blocks) {
+mp_uint_t external_flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_blocks) {
     for (size_t i = 0; i < num_blocks; i++) {
-        if (!spi_flash_read_block(dest + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) {
+        if (!external_flash_read_block(dest + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) {
             return 1; // error
         }
     }
     return 0; // success
 }
 
-mp_uint_t spi_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks) {
+mp_uint_t external_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks) {
     for (size_t i = 0; i < num_blocks; i++) {
-        if (!spi_flash_write_block(src + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) {
+        if (!external_flash_write_block(src + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) {
             return 1; // error
         }
     }
@@ -694,58 +579,58 @@ mp_uint_t spi_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_
 // Expose the flash as an object with the block protocol.
 
 // there is a singleton Flash object
-STATIC const mp_obj_base_t spi_flash_obj = {&spi_flash_type};
+STATIC const mp_obj_base_t external_flash_obj = {&external_flash_type};
 
-STATIC mp_obj_t spi_flash_obj_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+STATIC mp_obj_t external_flash_obj_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
     // check arguments
     mp_arg_check_num(n_args, n_kw, 0, 0, false);
 
     // return singleton object
-    return (mp_obj_t)&spi_flash_obj;
+    return (mp_obj_t)&external_flash_obj;
 }
 
-STATIC mp_obj_t spi_flash_obj_readblocks(mp_obj_t self, mp_obj_t block_num, mp_obj_t buf) {
+STATIC mp_obj_t external_flash_obj_readblocks(mp_obj_t self, mp_obj_t block_num, mp_obj_t buf) {
     mp_buffer_info_t bufinfo;
     mp_get_buffer_raise(buf, &bufinfo, MP_BUFFER_WRITE);
-    mp_uint_t ret = spi_flash_read_blocks(bufinfo.buf, mp_obj_get_int(block_num), bufinfo.len / FILESYSTEM_BLOCK_SIZE);
+    mp_uint_t ret = external_flash_read_blocks(bufinfo.buf, mp_obj_get_int(block_num), bufinfo.len / FILESYSTEM_BLOCK_SIZE);
     return MP_OBJ_NEW_SMALL_INT(ret);
 }
-STATIC MP_DEFINE_CONST_FUN_OBJ_3(spi_flash_obj_readblocks_obj, spi_flash_obj_readblocks);
+STATIC MP_DEFINE_CONST_FUN_OBJ_3(external_flash_obj_readblocks_obj, external_flash_obj_readblocks);
 
-STATIC mp_obj_t spi_flash_obj_writeblocks(mp_obj_t self, mp_obj_t block_num, mp_obj_t buf) {
+STATIC mp_obj_t external_flash_obj_writeblocks(mp_obj_t self, mp_obj_t block_num, mp_obj_t buf) {
     mp_buffer_info_t bufinfo;
     mp_get_buffer_raise(buf, &bufinfo, MP_BUFFER_READ);
-    mp_uint_t ret = spi_flash_write_blocks(bufinfo.buf, mp_obj_get_int(block_num), bufinfo.len / FILESYSTEM_BLOCK_SIZE);
+    mp_uint_t ret = external_flash_write_blocks(bufinfo.buf, mp_obj_get_int(block_num), bufinfo.len / FILESYSTEM_BLOCK_SIZE);
     return MP_OBJ_NEW_SMALL_INT(ret);
 }
-STATIC MP_DEFINE_CONST_FUN_OBJ_3(spi_flash_obj_writeblocks_obj, spi_flash_obj_writeblocks);
+STATIC MP_DEFINE_CONST_FUN_OBJ_3(external_flash_obj_writeblocks_obj, external_flash_obj_writeblocks);
 
-STATIC mp_obj_t spi_flash_obj_ioctl(mp_obj_t self, mp_obj_t cmd_in, mp_obj_t arg_in) {
+STATIC mp_obj_t external_flash_obj_ioctl(mp_obj_t self, mp_obj_t cmd_in, mp_obj_t arg_in) {
     mp_int_t cmd = mp_obj_get_int(cmd_in);
     switch (cmd) {
-        case BP_IOCTL_INIT: spi_flash_init(); return MP_OBJ_NEW_SMALL_INT(0);
-        case BP_IOCTL_DEINIT: spi_flash_flush(); return MP_OBJ_NEW_SMALL_INT(0); // TODO properly
-        case BP_IOCTL_SYNC: spi_flash_flush(); return MP_OBJ_NEW_SMALL_INT(0);
-        case BP_IOCTL_SEC_COUNT: return MP_OBJ_NEW_SMALL_INT(spi_flash_get_block_count());
-        case BP_IOCTL_SEC_SIZE: return MP_OBJ_NEW_SMALL_INT(spi_flash_get_block_size());
+        case BP_IOCTL_INIT: external_flash_init(); return MP_OBJ_NEW_SMALL_INT(0);
+        case BP_IOCTL_DEINIT: external_flash_flush(); return MP_OBJ_NEW_SMALL_INT(0); // TODO properly
+        case BP_IOCTL_SYNC: external_flash_flush(); return MP_OBJ_NEW_SMALL_INT(0);
+        case BP_IOCTL_SEC_COUNT: return MP_OBJ_NEW_SMALL_INT(external_flash_get_block_count());
+        case BP_IOCTL_SEC_SIZE: return MP_OBJ_NEW_SMALL_INT(external_flash_get_block_size());
         default: return mp_const_none;
     }
 }
-STATIC MP_DEFINE_CONST_FUN_OBJ_3(spi_flash_obj_ioctl_obj, spi_flash_obj_ioctl);
+STATIC MP_DEFINE_CONST_FUN_OBJ_3(external_flash_obj_ioctl_obj, external_flash_obj_ioctl);
 
-STATIC const mp_rom_map_elem_t spi_flash_obj_locals_dict_table[] = {
-    { MP_ROM_QSTR(MP_QSTR_readblocks), MP_ROM_PTR(&spi_flash_obj_readblocks_obj) },
-    { MP_ROM_QSTR(MP_QSTR_writeblocks), MP_ROM_PTR(&spi_flash_obj_writeblocks_obj) },
-    { MP_ROM_QSTR(MP_QSTR_ioctl), MP_ROM_PTR(&spi_flash_obj_ioctl_obj) },
+STATIC const mp_rom_map_elem_t external_flash_obj_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_readblocks), MP_ROM_PTR(&external_flash_obj_readblocks_obj) },
+    { MP_ROM_QSTR(MP_QSTR_writeblocks), MP_ROM_PTR(&external_flash_obj_writeblocks_obj) },
+    { MP_ROM_QSTR(MP_QSTR_ioctl), MP_ROM_PTR(&external_flash_obj_ioctl_obj) },
 };
 
-STATIC MP_DEFINE_CONST_DICT(spi_flash_obj_locals_dict, spi_flash_obj_locals_dict_table);
+STATIC MP_DEFINE_CONST_DICT(external_flash_obj_locals_dict, external_flash_obj_locals_dict_table);
 
-const mp_obj_type_t spi_flash_type = {
+const mp_obj_type_t external_flash_type = {
     { &mp_type_type },
     .name = MP_QSTR_SPIFlash,
-    .make_new = spi_flash_obj_make_new,
-    .locals_dict = (mp_obj_t)&spi_flash_obj_locals_dict,
+    .make_new = external_flash_obj_make_new,
+    .locals_dict = (mp_obj_t)&external_flash_obj_locals_dict,
 };
 
 void flash_init_vfs(fs_user_mount_t *vfs) {
@@ -753,12 +638,12 @@ void flash_init_vfs(fs_user_mount_t *vfs) {
     vfs->flags |= FSUSER_NATIVE | FSUSER_HAVE_IOCTL;
     vfs->fatfs.drv = vfs;
     vfs->fatfs.part = 1; // flash filesystem lives on first partition
-    vfs->readblocks[0] = (mp_obj_t)&spi_flash_obj_readblocks_obj;
-    vfs->readblocks[1] = (mp_obj_t)&spi_flash_obj;
-    vfs->readblocks[2] = (mp_obj_t)spi_flash_read_blocks; // native version
-    vfs->writeblocks[0] = (mp_obj_t)&spi_flash_obj_writeblocks_obj;
-    vfs->writeblocks[1] = (mp_obj_t)&spi_flash_obj;
-    vfs->writeblocks[2] = (mp_obj_t)spi_flash_write_blocks; // native version
-    vfs->u.ioctl[0] = (mp_obj_t)&spi_flash_obj_ioctl_obj;
-    vfs->u.ioctl[1] = (mp_obj_t)&spi_flash_obj;
+    vfs->readblocks[0] = (mp_obj_t)&external_flash_obj_readblocks_obj;
+    vfs->readblocks[1] = (mp_obj_t)&external_flash_obj;
+    vfs->readblocks[2] = (mp_obj_t)external_flash_read_blocks; // native version
+    vfs->writeblocks[0] = (mp_obj_t)&external_flash_obj_writeblocks_obj;
+    vfs->writeblocks[1] = (mp_obj_t)&external_flash_obj;
+    vfs->writeblocks[2] = (mp_obj_t)external_flash_write_blocks; // native version
+    vfs->u.ioctl[0] = (mp_obj_t)&external_flash_obj_ioctl_obj;
+    vfs->u.ioctl[1] = (mp_obj_t)&external_flash_obj;
 }
diff --git a/ports/atmel-samd/spi_flash.h b/ports/atmel-samd/external_flash/external_flash.h
similarity index 69%
rename from ports/atmel-samd/spi_flash.h
rename to ports/atmel-samd/external_flash/external_flash.h
index e4bf8a5224..5a43b10c84 100644
--- a/ports/atmel-samd/spi_flash.h
+++ b/ports/atmel-samd/external_flash/external_flash.h
@@ -23,8 +23,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#ifndef MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H
-#define MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H
+#ifndef MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_H
+#define MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_H
 
 #include <stdbool.h>
 
@@ -40,21 +40,21 @@
 #define SPI_FLASH_SYSTICK_MASK    (0x1ff) // 512ms
 #define SPI_FLASH_IDLE_TICK(tick) (((tick) & SPI_FLASH_SYSTICK_MASK) == 2)
 
-void spi_flash_init(void);
-uint32_t spi_flash_get_block_size(void);
-uint32_t spi_flash_get_block_count(void);
-void spi_flash_irq_handler(void);
-void spi_flash_flush(void);
-bool spi_flash_read_block(uint8_t *dest, uint32_t block);
-bool spi_flash_write_block(const uint8_t *src, uint32_t block);
+void external_flash_init(void);
+uint32_t external_flash_get_block_size(void);
+uint32_t external_flash_get_block_count(void);
+void external_flash_irq_handler(void);
+void external_flash_flush(void);
+bool external_flash_read_block(uint8_t *dest, uint32_t block);
+bool external_flash_write_block(const uint8_t *src, uint32_t block);
 
 // these return 0 on success, non-zero on error
-mp_uint_t spi_flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_blocks);
-mp_uint_t spi_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks);
+mp_uint_t external_flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_blocks);
+mp_uint_t external_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks);
 
-extern const struct _mp_obj_type_t spi_flash_type;
+extern const struct _mp_obj_type_t external_flash_type;
 
 struct _fs_user_mount_t;
 void flash_init_vfs(struct _fs_user_mount_t *vfs);
 
-#endif  // MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H
+#endif  // MICROPY_INCLUDED_ATMEL_SAMD_EXTERNAL_FLASH_H
diff --git a/ports/atmel-samd/external_flash/qspi_flash.c b/ports/atmel-samd/external_flash/qspi_flash.c
new file mode 100644
index 0000000000..d9dc3bf01e
--- /dev/null
+++ b/ports/atmel-samd/external_flash/qspi_flash.c
@@ -0,0 +1,196 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016, 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "spi_flash_api.h"
+
+#include <stdint.h>
+#include <string.h>
+
+#include "external_flash/common_commands.h"
+
+#include "atmel_start_pins.h"
+#include "hal_gpio.h"
+
+bool spi_flash_command(uint8_t command) {
+    QSPI->INSTRCTRL.bit.INSTR = command;
+
+    QSPI->INSTRFRAME.reg = QSPI_INSTRFRAME_WIDTH_SINGLE_BIT_SPI |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_READ |
+                           QSPI_INSTRFRAME_INSTREN;
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+bool spi_flash_read_command(uint8_t command, uint8_t* response, uint32_t length) {
+    QSPI->INSTRCTRL.bit.INSTR = command;
+
+    QSPI->INSTRFRAME.reg = QSPI_INSTRFRAME_WIDTH_SINGLE_BIT_SPI |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_READ |
+                           QSPI_INSTRFRAME_INSTREN |
+                           QSPI_INSTRFRAME_DATAEN;
+
+    memcpy(response, (uint8_t *) QSPI_AHB, length);
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+bool spi_flash_write_command(uint8_t command, uint8_t* data, uint32_t length) {
+    QSPI->INSTRCTRL.bit.INSTR = command;
+
+    QSPI->INSTRFRAME.reg = QSPI_INSTRFRAME_WIDTH_SINGLE_BIT_SPI |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_WRITE |
+                           QSPI_INSTRFRAME_INSTREN;
+
+    if (data != NULL) {
+        QSPI->INSTRFRAME.bit.DATAEN = true;
+
+        memcpy((uint8_t *) QSPI_AHB, data, length);
+    }
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+bool spi_flash_sector_command(uint8_t command, uint32_t address) {
+    QSPI->INSTRCTRL.bit.INSTR = command;
+    QSPI->INSTRADDR.bit.ADDR = address;
+
+    QSPI->INSTRFRAME.reg = QSPI_INSTRFRAME_WIDTH_SINGLE_BIT_SPI |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_WRITE |
+                           QSPI_INSTRFRAME_INSTREN |
+                           QSPI_INSTRFRAME_ADDREN;
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+bool spi_flash_write_data(uint32_t address, uint8_t* data, uint32_t length) {
+    QSPI->INSTRCTRL.bit.INSTR = CMD_PAGE_PROGRAM;
+    uint32_t mode = QSPI_INSTRFRAME_WIDTH_SINGLE_BIT_SPI;
+
+    QSPI->INSTRFRAME.reg = mode |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_WRITEMEMORY |
+                           QSPI_INSTRFRAME_INSTREN |
+                           QSPI_INSTRFRAME_ADDREN |
+                           QSPI_INSTRFRAME_DATAEN;
+
+    memcpy(((uint8_t *) QSPI_AHB) + address, data, length);
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+bool spi_flash_read_data(uint32_t address, uint8_t* data, uint32_t length) {
+    QSPI->INSTRCTRL.bit.INSTR = CMD_QUAD_READ;
+    uint32_t mode = QSPI_INSTRFRAME_WIDTH_QUAD_OUTPUT;
+
+    QSPI->INSTRFRAME.reg = mode |
+                           QSPI_INSTRFRAME_ADDRLEN_24BITS |
+                           QSPI_INSTRFRAME_TFRTYPE_READMEMORY |
+                           QSPI_INSTRFRAME_INSTREN |
+                           QSPI_INSTRFRAME_ADDREN |
+                           QSPI_INSTRFRAME_DATAEN |
+                           QSPI_INSTRFRAME_DUMMYLEN(8);
+
+    memcpy(data, ((uint8_t *) QSPI_AHB) + address, length);
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_ENABLE | QSPI_CTRLA_LASTXFER;
+
+    while( !QSPI->INTFLAG.bit.INSTREND );
+
+    QSPI->INTFLAG.reg = QSPI_INTFLAG_INSTREND;
+
+    return true;
+}
+
+
+void spi_flash_init(void) {
+    MCLK->APBCMASK.bit.QSPI_ = true;
+    MCLK->AHBMASK.bit.QSPI_ = true;
+    MCLK->AHBMASK.bit.QSPI_2X_ = false; // Only true if we are doing DDR.
+
+    QSPI->CTRLA.reg = QSPI_CTRLA_SWRST;
+    // We don't need to wait because we're running as fast as the CPU.
+
+    QSPI->BAUD.bit.BAUD = 10;
+    QSPI->CTRLB.reg = QSPI_CTRLB_MODE_MEMORY |
+                      QSPI_CTRLB_DATALEN_8BITS |
+                      QSPI_CTRLB_CSMODE_LASTXFER;
+
+    QSPI->CTRLA.bit.ENABLE = 1;
+
+    // The QSPI is only connected to one set of pins in the SAMD51 so we can hard code it.
+    uint32_t pins[6] = {PIN_PA08, PIN_PA09, PIN_PA10, PIN_PA11, PIN_PB10, PIN_PB11};
+    for (uint8_t i = 0; i < 6; i++) {
+        gpio_set_pin_direction(pins[i], GPIO_DIRECTION_IN);
+        gpio_set_pin_pull_mode(pins[i], GPIO_PULL_OFF);
+        gpio_set_pin_function(pins[i], GPIO_PIN_FUNCTION_H);
+    }
+
+    // Verify that QSPI mode is enabled.
+    uint8_t status;
+    spi_flash_read_command(0x35, &status, 1);
+
+    if ((status & 0x2) == 0) {
+        uint8_t full_status[3] = { 0, status | 0x2, 0x70};
+        spi_flash_command(CMD_ENABLE_WRITE);
+        spi_flash_write_command(0x01, full_status, 3);
+    }
+
+    asm("nop");
+}
diff --git a/ports/atmel-samd/external_flash/spi_flash.c b/ports/atmel-samd/external_flash/spi_flash.c
new file mode 100644
index 0000000000..4b63132eea
--- /dev/null
+++ b/ports/atmel-samd/external_flash/spi_flash.c
@@ -0,0 +1,139 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016, 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "spi_flash_api.h"
+
+#include <stdint.h>
+#include <string.h>
+
+#include "external_flash/common_commands.h"
+#include "peripherals.h"
+
+#include "hal_gpio.h"
+#include "hal_spi_m_sync.h"
+
+struct spi_m_sync_descriptor spi_flash_desc;
+
+// Enable the flash over SPI.
+static void flash_enable(void) {
+    gpio_set_pin_level(SPI_FLASH_CS_PIN, false);
+}
+
+// Disable the flash over SPI.
+static void flash_disable(void) {
+    gpio_set_pin_level(SPI_FLASH_CS_PIN, true);
+}
+
+static bool transfer(uint8_t* command, uint32_t command_length, uint8_t* data_in, uint8_t* data_out, uint32_t data_length) {
+    struct spi_xfer xfer = { command, NULL, command_length };
+    flash_enable();
+    int32_t status = spi_m_sync_transfer(&spi_flash_desc, &xfer);
+    if (status >= 0 && !(data_in == NULL && data_out == NULL)) {
+        struct spi_xfer data_xfer = {data_in, data_out, data_length};
+        status = spi_m_sync_transfer(&spi_flash_desc, &data_xfer);
+    }
+    flash_disable();
+    return status >= 0;
+}
+
+static bool transfer_command(uint8_t command, uint8_t* data_in, uint8_t* data_out, uint32_t data_length) {
+    return transfer(&command, 1, data_in, data_out, data_length);
+}
+
+bool spi_flash_command(uint8_t command) {
+    return transfer_command(command, NULL, NULL, 0);
+}
+
+bool spi_flash_read_command(uint8_t command, uint8_t* data, uint32_t data_length) {
+    return transfer_command(command, NULL, data, data_length);
+}
+
+bool spi_flash_write_command(uint8_t command, uint8_t* data, uint32_t data_length) {
+    return transfer_command(command, data, NULL, data_length);
+}
+
+// Pack the low 24 bits of the address into a uint8_t array.
+static void address_to_bytes(uint32_t address, uint8_t* bytes) {
+    bytes[0] = (address >> 16) & 0xff;
+    bytes[1] = (address >> 8) & 0xff;
+    bytes[2] = address & 0xff;
+}
+
+bool spi_flash_sector_command(uint8_t command, uint32_t address) {
+    uint8_t request[4] = {command, 0x00, 0x00, 0x00};
+    address_to_bytes(address, request + 1);
+    return transfer(request, 4, NULL, NULL, 0);
+}
+
+bool spi_flash_write_data(uint32_t address, uint8_t* data, uint32_t data_length) {
+    uint8_t request[4] = {CMD_PAGE_PROGRAM, 0x00, 0x00, 0x00};
+    // Write the SPI flash write address into the bytes following the command byte.
+    address_to_bytes(address, request + 1);
+    return transfer(request, 4, data, NULL, data_length);
+}
+
+bool spi_flash_read_data(uint32_t address, uint8_t* data, uint32_t data_length) {
+    uint8_t request[4] = {CMD_READ_DATA, 0x00, 0x00, 0x00};
+    // Write the SPI flash write address into the bytes following the command byte.
+    address_to_bytes(address, request + 1);
+    return transfer(request, 4, NULL, data, data_length);
+}
+
+void spi_flash_init(void) {
+    samd_peripherals_sercom_clock_init(SPI_FLASH_SERCOM, SPI_FLASH_SERCOM_INDEX);
+
+    // Set up with defaults, then change.
+    spi_m_sync_init(&spi_flash_desc, SPI_FLASH_SERCOM);
+
+    hri_sercomspi_write_CTRLA_DOPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DOPO);
+    hri_sercomspi_write_CTRLA_DIPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DIPO);
+
+    gpio_set_pin_direction(SPI_FLASH_SCK_PIN, GPIO_DIRECTION_OUT);
+    gpio_set_pin_pull_mode(SPI_FLASH_SCK_PIN, GPIO_PULL_OFF);
+    gpio_set_pin_function(SPI_FLASH_SCK_PIN, SPI_FLASH_SCK_PIN_FUNCTION);
+
+    gpio_set_pin_direction(SPI_FLASH_MOSI_PIN, GPIO_DIRECTION_OUT);
+    gpio_set_pin_pull_mode(SPI_FLASH_MOSI_PIN, GPIO_PULL_OFF);
+    gpio_set_pin_function(SPI_FLASH_MOSI_PIN, SPI_FLASH_MOSI_PIN_FUNCTION);
+
+    gpio_set_pin_direction(SPI_FLASH_MISO_PIN, GPIO_DIRECTION_IN);
+    gpio_set_pin_pull_mode(SPI_FLASH_MISO_PIN, GPIO_PULL_OFF);
+    gpio_set_pin_function(SPI_FLASH_MISO_PIN, SPI_FLASH_MISO_PIN_FUNCTION);
+
+    hri_sercomspi_write_CTRLA_DOPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DOPO);
+    hri_sercomspi_write_CTRLA_DIPO_bf(SPI_FLASH_SERCOM, SPI_FLASH_DIPO);
+
+    spi_m_sync_set_baudrate(&spi_flash_desc, samd_peripherals_spi_baudrate_to_baud_reg_value(SPI_FLASH_BAUDRATE));
+
+    gpio_set_pin_direction(SPI_FLASH_CS_PIN, GPIO_DIRECTION_OUT);
+    // There's already a pull-up on the board.
+    gpio_set_pin_pull_mode(SPI_FLASH_CS_PIN, GPIO_PULL_OFF);
+    gpio_set_pin_function(SPI_FLASH_CS_PIN, GPIO_PIN_FUNCTION_OFF);
+
+    // Set CS high (disabled).
+    flash_disable();
+
+    spi_m_sync_enable(&spi_flash_desc);
+}
diff --git a/ports/atmel-samd/external_flash/spi_flash_api.h b/ports/atmel-samd/external_flash/spi_flash_api.h
new file mode 100644
index 0000000000..b858ff0ea0
--- /dev/null
+++ b/ports/atmel-samd/external_flash/spi_flash_api.h
@@ -0,0 +1,42 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H
+#define MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+// This API is implemented for both normal SPI peripherals and QSPI peripherals.
+
+bool spi_flash_command(uint8_t command);
+bool spi_flash_read_command(uint8_t command, uint8_t* response, uint32_t length);
+bool spi_flash_write_command(uint8_t command, uint8_t* data, uint32_t length);
+bool spi_flash_sector_command(uint8_t command, uint32_t address);
+bool spi_flash_write_data(uint32_t address, uint8_t* data, uint32_t data_length);
+bool spi_flash_read_data(uint32_t address, uint8_t* data, uint32_t data_length);
+void spi_flash_init(void);
+
+#endif  // MICROPY_INCLUDED_ATMEL_SAMD_SPI_FLASH_H