diff --git a/examples/nxp/rt1060-evk-make-baremetal-builtin/main.c b/examples/nxp/rt1060-evk-make-baremetal-builtin/main.c
index 3fd164e5152..f3a18338085 100644
--- a/examples/nxp/rt1060-evk-make-baremetal-builtin/main.c
+++ b/examples/nxp/rt1060-evk-make-baremetal-builtin/main.c
@@ -22,6 +22,7 @@ void mg_random(void *buf, size_t len) {  // Use on-board RNG
     memcpy((char *) buf + n, &r, n + sizeof(r) > len ? len - n : sizeof(r));
   }
 }
+
 static void timer_fn(void *arg) {
   gpio_toggle(LED);                                      // Blink LED
   struct mg_tcpip_if *ifp = arg;                         // And show
@@ -32,15 +33,42 @@ static void timer_fn(void *arg) {
 }
 
 int main(void) {
-  gpio_output(LED);               // Setup blue LED
+  gpio_output(LED);               // Setup green LED
   uart_init(UART_DEBUG, 115200);  // Initialise debug printf
   ethernet_init();                // Initialise ethernet pins
+
+  #ifdef MQTT_DASHBOARD
+    // User can customise the MQTT url, device ID or the root topic below
+  #define DEVICE_ID "RT1060"
+    g_url = MQTT_SERVER_URL;
+    g_device_id = DEVICE_ID;
+    g_root_topic = DEFAULT_ROOT_TOPIC;
+  #endif
+
   MG_INFO(("Starting, CPU freq %g MHz", (double) SystemCoreClock / 1000000));
 
   struct mg_mgr mgr;        // Initialise
   mg_mgr_init(&mgr);        // Mongoose event manager
   mg_log_set(MG_LL_DEBUG);  // Set log level
 
+  //mg_ota_boot();  // Call bootloader: continue to load, or boot another FW
+
+#if MG_OTA == MG_OTA_FLASH
+  // Demonstrate the use of mg_flash_{load/save} functions for keeping device
+  // configuration data on flash. Increment boot count on every boot.
+  struct deviceconfig {
+    uint32_t boot_count;
+    char some_other_data[40];
+  };
+  uint32_t key = 0x12345678;    // A unique key, one per data type
+  struct deviceconfig dc = {};  // Initialise to some default values
+  mg_flash_load(NULL, key, &dc, sizeof(dc));  // Load from flash
+  dc.boot_count++;                            // Increment boot count
+  mg_flash_save(NULL, key, &dc, sizeof(dc));  // And save back
+  MG_INFO(("Boot count: %u", dc.boot_count));
+#endif
+
+  // Initialise Mongoose network stack
   // Initialise Mongoose network stack
   struct mg_tcpip_driver_imxrt_data driver_data = {.mdc_cr = 24, .phy_addr = 2};
   struct mg_tcpip_if mif = {.mac = GENERATE_LOCALLY_ADMINISTERED_MAC(),
@@ -65,6 +93,6 @@ int main(void) {
   for (;;) {
     mg_mgr_poll(&mgr, 0);
   }
-
   return 0;
 }
+
diff --git a/examples/nxp/rt1060-evk-make-baremetal-builtin/mongoose_custom.h b/examples/nxp/rt1060-evk-make-baremetal-builtin/mongoose_custom.h
index 450587c69a2..b7584012abe 100644
--- a/examples/nxp/rt1060-evk-make-baremetal-builtin/mongoose_custom.h
+++ b/examples/nxp/rt1060-evk-make-baremetal-builtin/mongoose_custom.h
@@ -2,6 +2,8 @@
 
 // See https://mongoose.ws/documentation/#build-options
 #define MG_ARCH MG_ARCH_NEWLIB
+#define MG_OTA MG_OTA_EXTERNAL_FLASH
+#define MG_DEVICE MG_DEVICE_RT1060_QUAD_NOR
 
 #define MG_ENABLE_TCPIP 1
 #define MG_ENABLE_DRIVER_IMXRT 1
diff --git a/examples/nxp/rt1060-evk-make-baremetal-builtin/net.c b/examples/nxp/rt1060-evk-make-baremetal-builtin/net.c
index fe0e6f06e7b..39be7659aca 120000
--- a/examples/nxp/rt1060-evk-make-baremetal-builtin/net.c
+++ b/examples/nxp/rt1060-evk-make-baremetal-builtin/net.c
@@ -1 +1 @@
-../../device-dashboard/net.c
\ No newline at end of file
+../../mqtt-dashboard/device/net.c
\ No newline at end of file
diff --git a/examples/nxp/rt1060-evk-make-baremetal-builtin/net.h b/examples/nxp/rt1060-evk-make-baremetal-builtin/net.h
index 9de896ef4e3..cb6bd99fed3 120000
--- a/examples/nxp/rt1060-evk-make-baremetal-builtin/net.h
+++ b/examples/nxp/rt1060-evk-make-baremetal-builtin/net.h
@@ -1 +1 @@
-../../device-dashboard/net.h
\ No newline at end of file
+../../mqtt-dashboard/device/net.h
\ No newline at end of file
diff --git a/mongoose.c b/mongoose.c
index 9be9e5a1103..c1b04e671c4 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -323,6 +323,201 @@ bool mg_flash_load(void *sector, uint32_t key, void *buf, size_t len) {
 }
 #endif
 
+#ifdef MG_ENABLE_LINES
+#line 1 "src/device_rt1060_quad_nor.c"
+#endif
+
+
+
+#if MG_DEVICE == MG_DEVICE_RT1060_QUAD_NOR
+
+typedef struct {
+  char memCfg[448];
+  uint32_t pageSize;
+  uint32_t sectorSize;
+  uint32_t ipCmdSerialClkFreq;
+  char reserved[55];
+} flexspi_nor_config_t;
+
+typedef struct _serial_nor_config_option
+{
+  union
+  {
+    struct
+    {
+      uint32_t max_freq : 4; //!< Maximum supported Frequency
+      uint32_t misc_mode : 4; //!< miscellaneous mode
+      uint32_t quad_mode_setting : 4; //!< Quad mode setting
+      uint32_t cmd_pads : 4; //!< Command pads
+      uint32_t query_pads : 4; //!< SFDP read pads
+      uint32_t device_type : 4; //!< Device type
+      uint32_t option_size : 4; //!< Option size, in terms of uint32_t, size = (option_size + 1) * 4
+      uint32_t tag : 4; //!< Tag, must be 0x0E
+    } B;
+      uint32_t U;
+      } option0;
+  union
+  {
+    struct
+    {
+      uint32_t dummy_cycles : 8; //!< Dummy cycles before read
+      uint32_t reserved0 : 8; //!< Reserved for future use
+      uint32_t pinmux_group : 4; //!< The pinmux group selection
+      uint32_t reserved1 : 8; //!< Reserved for future use
+      uint32_t flash_connection : 4; //!< Flash connection option: 0 - Single Flash connected to port A
+    } B;
+      uint32_t U;
+      } option1;
+} serial_nor_config_option_t;
+
+typedef int status_t;
+
+typedef enum _FlexSPIOperationType
+{
+ kFlexSpiOperation_Command, //!< FlexSPI operation: Only command, both TX and
+ //! RX buffer are ignored.
+ kFlexSpiOperation_Config, //!< FlexSPI operation: Configure device mode, the
+ //! TX FIFO size is fixed in LUT.
+ kFlexSpiOperation_Write, //!< FlexSPI operation: Write, only TX buffer is
+ //! effective
+ kFlexSpiOperation_Read, //!< FlexSPI operation: Read, only Rx Buffer is
+ kFlexSpiOperation_End = kFlexSpiOperation_Read,
+} flexspi_operation_t; 
+
+typedef struct _FlexSpiXfer
+{
+ flexspi_operation_t operation; //!< FlexSPI operation
+ uint32_t baseAddress; //!< FlexSPI operation base address
+ uint32_t seqId; //!< Sequence Id
+ uint32_t seqNum; //!< Sequence Number
+ bool isParallelModeEnable; //!< Is a parallel transfer
+ uint32_t *txBuffer; //!< Tx buffer
+ uint32_t txSize; //!< Tx size in bytes
+ uint32_t *rxBuffer; //!< Rx buffer
+ uint32_t rxSize; //!< Rx size in bytes
+} flexspi_xfer_t;
+
+typedef struct
+{
+ uint32_t version;
+ status_t (*init)(uint32_t instance, flexspi_nor_config_t *config);
+ status_t (*program)(uint32_t instance, flexspi_nor_config_t *config, uint32_t
+dst_addr, const uint32_t *src);
+ status_t (*erase_all)(uint32_t instance, flexspi_nor_config_t *config);
+ status_t (*erase)(uint32_t instance, flexspi_nor_config_t *config, uint32_t start,
+uint32_t lengthInBytes);
+ status_t (*read)(
+ uint32_t instance, flexspi_nor_config_t *config, uint32_t *dst, uint32_t addr,
+uint32_t lengthInBytes);
+ void (*clear_cache)(uint32_t instance);
+ status_t (*xfer)(uint32_t instance, flexspi_xfer_t *xfer);
+ status_t (*update_lut)(uint32_t instance, uint32_t seqIndex, const uint32_t
+*lutBase, uint32_t seqNumber);
+ status_t (*get_config)(uint32_t instance, flexspi_nor_config_t *config,
+serial_nor_config_option_t *option);
+} flexspi_nor_driver_interface_t;
+
+typedef struct
+{
+ const uint32_t version; //!< Bootloader version number
+ const char *copyright; //!< Bootloader Copyright
+ void (*runBootloader)(void *arg); //!< Function to start the bootloader executing
+ const uint32_t *reserved0; //!< Reserved
+ const flexspi_nor_driver_interface_t *flexSpiNorDriver; //!< FlexSPI NOR Flash API
+ const uint32_t *reserved1[2]; //!< Reserved
+ /*const rtwdog_driver_interface_t *rtwdogDriver;
+ const wdog_driver_interface_t *wdogDriver;
+ const uint32_t *reserved2;*/
+} bootloader_api_entry_t;
+
+#define bootloader (*(bootloader_api_entry_t**)(0x0020001c))
+#define flexspi_nor (*(flexspi_nor_driver_interface_t**) ((char*) bootloader + 4*sizeof(uint32_t)))
+
+static flexspi_nor_config_t s_config;
+static serial_nor_config_option_t s_option;
+static uint32_t s_instance;
+
+void *mg_flash_start(void) {
+  return (void *) 0x0;
+}
+size_t mg_flash_size(void) {
+  return 256 * 1024; // 256k
+}
+size_t mg_flash_sector_size(void) {
+  return 4 * 1024;  // 4k
+}
+size_t mg_flash_write_align(void) {
+  return 256;
+}
+int mg_flash_bank(void) {
+  return 0;
+}
+
+static bool flash_page_start(volatile uint32_t *dst) {
+  char *base = (char *) mg_flash_start(), *end = base + mg_flash_size();
+  volatile char *p = (char *) dst;
+  return p >= base && p < end && ((p - base) % mg_flash_sector_size()) == 0;
+}
+
+uint32_t mg_flash_init() {
+  uint32_t status = 0;
+  s_option.option0.U = 0xc0000008;
+  status = flexspi_nor->get_config(s_instance, &s_config, &s_option);
+  if (status != 0) {
+    MG_DEBUG(("Failed to get flexspi configuration"));
+    return status;
+  }
+
+  status = flexspi_nor->init(s_instance, &s_config);
+  return status;
+}
+
+bool mg_flash_erase(void *addr) {
+  bool ok = false;
+  if (flash_page_start(addr) == false) {
+    MG_ERROR(("%p is not on a sector boundary", addr));
+  } else {
+    uint32_t status = flexspi_nor->erase(s_instance, &s_config, (uint32_t) addr, mg_flash_sector_size());
+    if (status == 0) ok = true; 
+  }
+  if (ok) {
+    MG_DEBUG(("Successfully erased sector starting at %p", addr));
+  } else {
+    MG_DEBUG(("Failed to erase sector starting at %p", addr));
+  }
+  return ok;
+}
+
+bool mg_flash_swap_bank() {
+  return false;
+}
+
+bool mg_flash_write(void *addr, const void *buf, size_t len) {
+  if ((len % mg_flash_write_align()) != 0) {
+    MG_ERROR(("%lu is not aligned to %lu", len, mg_flash_write_align()));
+    return false;
+  }
+  uint32_t *dst = (uint32_t *) addr;
+  uint32_t *src = (uint32_t *) buf;
+  uint32_t *end = (uint32_t *) ((char *) buf + len);
+  bool ok = true;
+  while (ok && src < end) {
+    if (flash_page_start(dst) && mg_flash_erase(dst) == false) break;
+    uint32_t status = flexspi_nor->program(s_instance, &s_config, (uint32_t) dst, src);
+    src = (uint32_t *) ((char *) src + mg_flash_write_align());
+    dst = (uint32_t *) ((char *) dst + mg_flash_write_align());
+    if (status != 0) ok = false;
+  }
+  MG_DEBUG(("Flash write %lu bytes @ %p: %s.", len, dst,
+            ok ? "ok" : "fail"));
+  return ok;
+}
+
+void mg_device_reset(void) {
+  *(volatile unsigned long *) 0xe000ed0c = 0x5fa0004;
+}
+#endif
+
 #ifdef MG_ENABLE_LINES
 #line 1 "src/device_stm32h5.c"
 #endif
@@ -5700,6 +5895,107 @@ MG_IRAM void mg_ota_boot(void) {
     mg_device_reset();
   }
 }
+
+#elif MG_OTA == MG_OTA_EXTERNAL_FLASH
+
+static char *s_addr;      // Current address to write to
+static size_t s_size;     // Firmware size to flash. In-progress indicator
+static uint32_t s_crc32;  // Firmware checksum
+
+struct mg_otadata {
+  uint32_t crc32, size, timestamp, status;
+};
+
+bool mg_ota_begin(size_t new_firmware_size) {
+  bool ok = false;
+  if (s_size) {
+    MG_ERROR(("OTA already in progress. Call mg_ota_end()"));
+  } else {
+    if (new_firmware_size > mg_flash_size()) {
+      MG_ERROR(("Firmware exceeds flash size"));
+      return false;
+    }
+    s_size = new_firmware_size;
+    uint32_t flash_init_status = mg_flash_init();
+    if (flash_init_status) {
+      MG_ERROR(("Error initialising the flash structure"));
+      return false;
+    } else {
+      ok = true;
+    }
+  }
+  return ok;
+}
+
+bool mg_ota_write(const void *buf, size_t len) {
+  bool ok = false;
+  if (s_size == 0) {
+    MG_ERROR(("OTA is not started, call mg_ota_begin()"));
+  } else {
+    size_t align = mg_flash_write_align();
+    size_t len_aligned_down = MG_ROUND_DOWN(len, align);
+    if (len_aligned_down) ok = mg_flash_write(s_addr, buf, len_aligned_down);
+    if (len_aligned_down < len) {
+      size_t left = len - len_aligned_down;
+      char tmp[align];
+      memset(tmp, 0xff, sizeof(tmp));
+      memcpy(tmp, (char *) buf + len_aligned_down, left);
+      ok = mg_flash_write(s_addr + len_aligned_down, tmp, sizeof(tmp));
+    }
+    s_crc32 = mg_crc32(s_crc32, (char *) buf, len);  // Update CRC
+    MG_DEBUG(("%#x %p %lu -> %d", s_addr, buf, len, ok));
+    s_addr += len;
+  }
+  return ok;
+}
+
+bool mg_ota_end(void) {
+  bool ok = true;
+  size_t size = (size_t) s_addr;
+  uint32_t crc32 = mg_crc32(0, (char *) 0x60000000, size);
+  MG_DEBUG(("CRC: %x/%x, size: %lu/%lu, status: %s", s_crc32, crc32, s_size,
+              size, s_crc32 == crc32 ? "ok" : "fail"));
+  s_addr = 0;
+  s_size = 0;
+  MG_INFO(("Finishing OTA: %s", ok ? "ok" : "fail"));
+  return ok;
+}
+
+static struct mg_otadata mg_otadata(int fw) {
+  (void) fw;
+  struct mg_otadata od = {};
+  return od;
+}
+
+int mg_ota_status(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.status;
+}
+
+uint32_t mg_ota_crc32(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.crc32;
+}
+
+uint32_t mg_ota_timestamp(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.timestamp;
+}
+
+size_t mg_ota_size(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.size;
+}
+
+MG_IRAM bool mg_ota_commit(void) {
+  return false;
+}
+
+bool mg_ota_rollback(void) {
+  MG_DEBUG(("Rolling firmware not supported yet"));
+  return false;
+}
+
 #endif
 
 #ifdef MG_ENABLE_LINES
@@ -9309,7 +9605,7 @@ void ETH_IRQHandler(void) {
     }
   }
 #ifdef __riscv
-  ETH->DMASR = ~0;   // TODO: do more fine-grained flag cleanup
+  ETH->DMASR = ~0;  // TODO: do more fine-grained flag cleanup
 #else
   ETH->DMASR = MG_BIT(7);  // Clear possible RBUS while processing
 #endif
diff --git a/mongoose.h b/mongoose.h
index c4464188606..4fe84e416c0 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -1692,6 +1692,7 @@ void mg_rpc_list(struct mg_rpc_req *r);
 
 #define MG_OTA_NONE 0      // No OTA support
 #define MG_OTA_FLASH 1     // OTA via an internal flash
+#define MG_OTA_EXTERNAL_FLASH 2 // OTA via an external flash
 #define MG_OTA_CUSTOM 100  // Custom implementation
 
 #ifndef MG_OTA
@@ -1735,6 +1736,7 @@ MG_IRAM void mg_ota_boot(void);  // Bootloader function
 #define MG_DEVICE_NONE 0      // Dummy system
 #define MG_DEVICE_STM32H5 1   // STM32 H5
 #define MG_DEVICE_STM32H7 2   // STM32 H7
+#define MG_DEVICE_RT1060_QUAD_NOR 3 // IMXRT1060 QUAD SPI NOR FLASH
 #define MG_DEVICE_CUSTOM 100  // Custom implementation
 
 #ifndef MG_DEVICE
diff --git a/src/device.h b/src/device.h
index 99b1064bd81..8c3ccc6337f 100644
--- a/src/device.h
+++ b/src/device.h
@@ -8,6 +8,7 @@
 #define MG_DEVICE_NONE 0      // Dummy system
 #define MG_DEVICE_STM32H5 1   // STM32 H5
 #define MG_DEVICE_STM32H7 2   // STM32 H7
+#define MG_DEVICE_RT1060_QUAD_NOR 3 // IMXRT1060 QUAD SPI NOR FLASH
 #define MG_DEVICE_CUSTOM 100  // Custom implementation
 
 #ifndef MG_DEVICE
diff --git a/src/device_rt1060_quad_nor.c b/src/device_rt1060_quad_nor.c
new file mode 100644
index 00000000000..8218b7c9eac
--- /dev/null
+++ b/src/device_rt1060_quad_nor.c
@@ -0,0 +1,191 @@
+#include "device.h"
+#include "log.h"
+
+#if MG_DEVICE == MG_DEVICE_RT1060_QUAD_NOR
+
+typedef struct {
+  char memCfg[448];
+  uint32_t pageSize;
+  uint32_t sectorSize;
+  uint32_t ipCmdSerialClkFreq;
+  char reserved[55];
+} flexspi_nor_config_t;
+
+typedef struct _serial_nor_config_option
+{
+  union
+  {
+    struct
+    {
+      uint32_t max_freq : 4; //!< Maximum supported Frequency
+      uint32_t misc_mode : 4; //!< miscellaneous mode
+      uint32_t quad_mode_setting : 4; //!< Quad mode setting
+      uint32_t cmd_pads : 4; //!< Command pads
+      uint32_t query_pads : 4; //!< SFDP read pads
+      uint32_t device_type : 4; //!< Device type
+      uint32_t option_size : 4; //!< Option size, in terms of uint32_t, size = (option_size + 1) * 4
+      uint32_t tag : 4; //!< Tag, must be 0x0E
+    } B;
+      uint32_t U;
+      } option0;
+  union
+  {
+    struct
+    {
+      uint32_t dummy_cycles : 8; //!< Dummy cycles before read
+      uint32_t reserved0 : 8; //!< Reserved for future use
+      uint32_t pinmux_group : 4; //!< The pinmux group selection
+      uint32_t reserved1 : 8; //!< Reserved for future use
+      uint32_t flash_connection : 4; //!< Flash connection option: 0 - Single Flash connected to port A
+    } B;
+      uint32_t U;
+      } option1;
+} serial_nor_config_option_t;
+
+typedef int status_t;
+
+typedef enum _FlexSPIOperationType
+{
+ kFlexSpiOperation_Command, //!< FlexSPI operation: Only command, both TX and
+ //! RX buffer are ignored.
+ kFlexSpiOperation_Config, //!< FlexSPI operation: Configure device mode, the
+ //! TX FIFO size is fixed in LUT.
+ kFlexSpiOperation_Write, //!< FlexSPI operation: Write, only TX buffer is
+ //! effective
+ kFlexSpiOperation_Read, //!< FlexSPI operation: Read, only Rx Buffer is
+ kFlexSpiOperation_End = kFlexSpiOperation_Read,
+} flexspi_operation_t; 
+
+typedef struct _FlexSpiXfer
+{
+ flexspi_operation_t operation; //!< FlexSPI operation
+ uint32_t baseAddress; //!< FlexSPI operation base address
+ uint32_t seqId; //!< Sequence Id
+ uint32_t seqNum; //!< Sequence Number
+ bool isParallelModeEnable; //!< Is a parallel transfer
+ uint32_t *txBuffer; //!< Tx buffer
+ uint32_t txSize; //!< Tx size in bytes
+ uint32_t *rxBuffer; //!< Rx buffer
+ uint32_t rxSize; //!< Rx size in bytes
+} flexspi_xfer_t;
+
+typedef struct
+{
+ uint32_t version;
+ status_t (*init)(uint32_t instance, flexspi_nor_config_t *config);
+ status_t (*program)(uint32_t instance, flexspi_nor_config_t *config, uint32_t
+dst_addr, const uint32_t *src);
+ status_t (*erase_all)(uint32_t instance, flexspi_nor_config_t *config);
+ status_t (*erase)(uint32_t instance, flexspi_nor_config_t *config, uint32_t start,
+uint32_t lengthInBytes);
+ status_t (*read)(
+ uint32_t instance, flexspi_nor_config_t *config, uint32_t *dst, uint32_t addr,
+uint32_t lengthInBytes);
+ void (*clear_cache)(uint32_t instance);
+ status_t (*xfer)(uint32_t instance, flexspi_xfer_t *xfer);
+ status_t (*update_lut)(uint32_t instance, uint32_t seqIndex, const uint32_t
+*lutBase, uint32_t seqNumber);
+ status_t (*get_config)(uint32_t instance, flexspi_nor_config_t *config,
+serial_nor_config_option_t *option);
+} flexspi_nor_driver_interface_t;
+
+typedef struct
+{
+ const uint32_t version; //!< Bootloader version number
+ const char *copyright; //!< Bootloader Copyright
+ void (*runBootloader)(void *arg); //!< Function to start the bootloader executing
+ const uint32_t *reserved0; //!< Reserved
+ const flexspi_nor_driver_interface_t *flexSpiNorDriver; //!< FlexSPI NOR Flash API
+ const uint32_t *reserved1[2]; //!< Reserved
+ /*const rtwdog_driver_interface_t *rtwdogDriver;
+ const wdog_driver_interface_t *wdogDriver;
+ const uint32_t *reserved2;*/
+} bootloader_api_entry_t;
+
+#define bootloader (*(bootloader_api_entry_t**)(0x0020001c))
+#define flexspi_nor (*(flexspi_nor_driver_interface_t**) ((char*) bootloader + 4*sizeof(uint32_t)))
+
+static flexspi_nor_config_t s_config;
+static serial_nor_config_option_t s_option;
+static uint32_t s_instance;
+
+void *mg_flash_start(void) {
+  return (void *) 0x0;
+}
+size_t mg_flash_size(void) {
+  return 256 * 1024; // 256k
+}
+size_t mg_flash_sector_size(void) {
+  return 4 * 1024;  // 4k
+}
+size_t mg_flash_write_align(void) {
+  return 256;
+}
+int mg_flash_bank(void) {
+  return 0;
+}
+
+static bool flash_page_start(volatile uint32_t *dst) {
+  char *base = (char *) mg_flash_start(), *end = base + mg_flash_size();
+  volatile char *p = (char *) dst;
+  return p >= base && p < end && ((p - base) % mg_flash_sector_size()) == 0;
+}
+
+uint32_t mg_flash_init() {
+  uint32_t status = 0;
+  s_option.option0.U = 0xc0000008;
+  status = flexspi_nor->get_config(s_instance, &s_config, &s_option);
+  if (status != 0) {
+    MG_DEBUG(("Failed to get flexspi configuration"));
+    return status;
+  }
+
+  status = flexspi_nor->init(s_instance, &s_config);
+  return status;
+}
+
+bool mg_flash_erase(void *addr) {
+  bool ok = false;
+  if (flash_page_start(addr) == false) {
+    MG_ERROR(("%p is not on a sector boundary", addr));
+  } else {
+    uint32_t status = flexspi_nor->erase(s_instance, &s_config, (uint32_t) addr, mg_flash_sector_size());
+    if (status == 0) ok = true; 
+  }
+  if (ok) {
+    MG_DEBUG(("Successfully erased sector starting at %p", addr));
+  } else {
+    MG_DEBUG(("Failed to erase sector starting at %p", addr));
+  }
+  return ok;
+}
+
+bool mg_flash_swap_bank() {
+  return false;
+}
+
+bool mg_flash_write(void *addr, const void *buf, size_t len) {
+  if ((len % mg_flash_write_align()) != 0) {
+    MG_ERROR(("%lu is not aligned to %lu", len, mg_flash_write_align()));
+    return false;
+  }
+  uint32_t *dst = (uint32_t *) addr;
+  uint32_t *src = (uint32_t *) buf;
+  uint32_t *end = (uint32_t *) ((char *) buf + len);
+  bool ok = true;
+  while (ok && src < end) {
+    if (flash_page_start(dst) && mg_flash_erase(dst) == false) break;
+    uint32_t status = flexspi_nor->program(s_instance, &s_config, (uint32_t) dst, src);
+    src = (uint32_t *) ((char *) src + mg_flash_write_align());
+    dst = (uint32_t *) ((char *) dst + mg_flash_write_align());
+    if (status != 0) ok = false;
+  }
+  MG_DEBUG(("Flash write %lu bytes @ %p: %s.", len, dst,
+            ok ? "ok" : "fail"));
+  return ok;
+}
+
+void mg_device_reset(void) {
+  *(volatile unsigned long *) 0xe000ed0c = 0x5fa0004;
+}
+#endif
diff --git a/src/ota.h b/src/ota.h
index 7eae2a496a0..5cadd9e6b25 100644
--- a/src/ota.h
+++ b/src/ota.h
@@ -7,6 +7,7 @@
 
 #define MG_OTA_NONE 0      // No OTA support
 #define MG_OTA_FLASH 1     // OTA via an internal flash
+#define MG_OTA_EXTERNAL_FLASH 2 // OTA via an external flash
 #define MG_OTA_CUSTOM 100  // Custom implementation
 
 #ifndef MG_OTA
diff --git a/src/ota_flash.c b/src/ota_flash.c
index d5fe87b05b5..4084e41f707 100644
--- a/src/ota_flash.c
+++ b/src/ota_flash.c
@@ -192,4 +192,105 @@ MG_IRAM void mg_ota_boot(void) {
     mg_device_reset();
   }
 }
+
+#elif MG_OTA == MG_OTA_EXTERNAL_FLASH
+
+static char *s_addr;      // Current address to write to
+static size_t s_size;     // Firmware size to flash. In-progress indicator
+static uint32_t s_crc32;  // Firmware checksum
+
+struct mg_otadata {
+  uint32_t crc32, size, timestamp, status;
+};
+
+bool mg_ota_begin(size_t new_firmware_size) {
+  bool ok = false;
+  if (s_size) {
+    MG_ERROR(("OTA already in progress. Call mg_ota_end()"));
+  } else {
+    if (new_firmware_size > mg_flash_size()) {
+      MG_ERROR(("Firmware exceeds flash size"));
+      return false;
+    }
+    s_size = new_firmware_size;
+    uint32_t flash_init_status = mg_flash_init();
+    if (flash_init_status) {
+      MG_ERROR(("Error initialising the flash structure"));
+      return false;
+    } else {
+      ok = true;
+    }
+  }
+  return ok;
+}
+
+bool mg_ota_write(const void *buf, size_t len) {
+  bool ok = false;
+  if (s_size == 0) {
+    MG_ERROR(("OTA is not started, call mg_ota_begin()"));
+  } else {
+    size_t align = mg_flash_write_align();
+    size_t len_aligned_down = MG_ROUND_DOWN(len, align);
+    if (len_aligned_down) ok = mg_flash_write(s_addr, buf, len_aligned_down);
+    if (len_aligned_down < len) {
+      size_t left = len - len_aligned_down;
+      char tmp[align];
+      memset(tmp, 0xff, sizeof(tmp));
+      memcpy(tmp, (char *) buf + len_aligned_down, left);
+      ok = mg_flash_write(s_addr + len_aligned_down, tmp, sizeof(tmp));
+    }
+    s_crc32 = mg_crc32(s_crc32, (char *) buf, len);  // Update CRC
+    MG_DEBUG(("%#x %p %lu -> %d", s_addr, buf, len, ok));
+    s_addr += len;
+  }
+  return ok;
+}
+
+bool mg_ota_end(void) {
+  bool ok = true;
+  size_t size = (size_t) s_addr;
+  uint32_t crc32 = mg_crc32(0, (char *) 0x60000000, size);
+  MG_DEBUG(("CRC: %x/%x, size: %lu/%lu, status: %s", s_crc32, crc32, s_size,
+              size, s_crc32 == crc32 ? "ok" : "fail"));
+  s_addr = 0;
+  s_size = 0;
+  MG_INFO(("Finishing OTA: %s", ok ? "ok" : "fail"));
+  return ok;
+}
+
+static struct mg_otadata mg_otadata(int fw) {
+  (void) fw;
+  struct mg_otadata od = {};
+  return od;
+}
+
+int mg_ota_status(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.status;
+}
+
+uint32_t mg_ota_crc32(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.crc32;
+}
+
+uint32_t mg_ota_timestamp(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.timestamp;
+}
+
+size_t mg_ota_size(int fw) {
+  struct mg_otadata od = mg_otadata(fw);
+  return od.size;
+}
+
+MG_IRAM bool mg_ota_commit(void) {
+  return false;
+}
+
+bool mg_ota_rollback(void) {
+  MG_DEBUG(("Rolling firmware not supported yet"));
+  return false;
+}
+
 #endif