diff --git a/cmake/stm32f3.cmake b/cmake/stm32f3.cmake
index 2d0ef50704..5410d45b43 100644
--- a/cmake/stm32f3.cmake
+++ b/cmake/stm32f3.cmake
@@ -19,6 +19,8 @@ main_sources(STM32F3_SRC
     target/system_stm32f30x.c
 
     config/config_streamer_stm32f3.c
+    config/config_streamer_ram.c
+    config/config_streamer_extflash.c
 
     drivers/adc_stm32f30x.c
     drivers/bus_i2c_stm32f30x.c
diff --git a/cmake/stm32f4.cmake b/cmake/stm32f4.cmake
index 47fbe8eab7..64fae1fe2f 100644
--- a/cmake/stm32f4.cmake
+++ b/cmake/stm32f4.cmake
@@ -36,6 +36,8 @@ main_sources(STM32F4_SRC
     target/system_stm32f4xx.c
 
     config/config_streamer_stm32f4.c
+    config/config_streamer_ram.c
+    config/config_streamer_extflash.c
 
     drivers/adc_stm32f4xx.c
     drivers/adc_stm32f4xx.c
diff --git a/cmake/stm32f7.cmake b/cmake/stm32f7.cmake
index 238920bcf8..6aa2a9fd80 100644
--- a/cmake/stm32f7.cmake
+++ b/cmake/stm32f7.cmake
@@ -61,6 +61,8 @@ main_sources(STM32F7_SRC
     target/system_stm32f7xx.c
 
     config/config_streamer_stm32f7.c
+    config/config_streamer_ram.c
+    config/config_streamer_extflash.c
 
     drivers/adc_stm32f7xx.c
     drivers/bus_i2c_hal.c
diff --git a/cmake/stm32h7.cmake b/cmake/stm32h7.cmake
index 758f9dca25..2f232a4600 100644
--- a/cmake/stm32h7.cmake
+++ b/cmake/stm32h7.cmake
@@ -142,6 +142,8 @@ main_sources(STM32H7_SRC
     target/system_stm32h7xx.c
 
     config/config_streamer_stm32h7.c
+    config/config_streamer_ram.c
+    config/config_streamer_extflash.c
 
     drivers/adc_stm32h7xx.c
     drivers/bus_i2c_hal.c
@@ -217,4 +219,4 @@ macro(define_target_stm32h7 subfamily size)
     endfunction()
 endmacro()
 
-define_target_stm32h7(43 i)
\ No newline at end of file
+define_target_stm32h7(43 i)
diff --git a/src/main/build/build_config.h b/src/main/build/build_config.h
index ae4eb1a3a4..2ded047b05 100644
--- a/src/main/build/build_config.h
+++ b/src/main/build/build_config.h
@@ -53,8 +53,10 @@
 
 #ifdef STM32H7
 #define DMA_RAM __attribute__ ((section(".DMA_RAM")))
+#define SLOW_RAM __attribute__ ((section(".SLOW_RAM")))
 #else
 #define DMA_RAM
+#define SLOW_RAM
 #endif
 
 #define STATIC_FASTRAM              static FASTRAM
diff --git a/src/main/config/config_eeprom.c b/src/main/config/config_eeprom.c
index e59c42b700..f64b2bb8a6 100755
--- a/src/main/config/config_eeprom.c
+++ b/src/main/config/config_eeprom.c
@@ -25,12 +25,14 @@
 #include "build/build_config.h"
 
 #include "common/crc.h"
+#include "common/utils.h"
 
 #include "config/config_eeprom.h"
 #include "config/config_streamer.h"
 #include "config/parameter_group.h"
 
 #include "drivers/system.h"
+#include "drivers/flash.h"
 
 #include "fc/config.h"
 
@@ -76,6 +78,31 @@ typedef struct {
     uint32_t word;
 } PG_PACKED packingTest_t;
 
+#if defined(CONFIG_IN_EXTERNAL_FLASH)
+bool loadEEPROMFromExternalFlash(void)
+{
+    const flashPartition_t *flashPartition = flashPartitionFindByType(FLASH_PARTITION_TYPE_CONFIG);
+    const flashGeometry_t *flashGeometry = flashGetGeometry();
+
+    uint32_t flashStartAddress = flashPartition->startSector * flashGeometry->sectorSize;
+
+    uint32_t totalBytesRead = 0;
+    int bytesRead = 0;
+
+    bool success = false;
+
+    do {
+        bytesRead = flashReadBytes(flashStartAddress + totalBytesRead, &eepromData[totalBytesRead], EEPROM_SIZE - totalBytesRead);
+        if (bytesRead > 0) {
+            totalBytesRead += bytesRead;
+            success = (totalBytesRead == EEPROM_SIZE);
+        }
+    } while (!success && bytesRead > 0);
+
+    return success;
+}
+#endif /* defined(CONFIG_IN_EXTERNAL_FLASH) */
+
 void initEEPROM(void)
 {
     // Verify that this architecture packs as expected.
@@ -86,6 +113,14 @@ void initEEPROM(void)
     BUILD_BUG_ON(sizeof(configHeader_t) != 1);
     BUILD_BUG_ON(sizeof(configFooter_t) != 2);
     BUILD_BUG_ON(sizeof(configRecord_t) != 6);
+
+#if defined(CONFIG_IN_EXTERNAL_FLASH)
+    bool eepromLoaded = loadEEPROMFromExternalFlash();
+    if (!eepromLoaded) {
+        // Flash read failed - just die now
+        failureMode(FAILURE_FLASH_READ_FAILED);
+    }
+#endif
 }
 
 static uint16_t updateCRC(uint16_t crc, const void *data, uint32_t length)
@@ -217,7 +252,9 @@ static bool writeSettingsToEEPROM(void)
         .format = EEPROM_CONF_VERSION,
     };
 
-    config_streamer_write(&streamer, (uint8_t *)&header, sizeof(header));
+    if (config_streamer_write(&streamer, (uint8_t *)&header, sizeof(header)) < 0) {
+        return false;
+    }
     uint16_t crc = updateCRC(0, (uint8_t *)&header, sizeof(header));
     PG_FOREACH(reg) {
         const uint16_t regSize = pgSize(reg);
@@ -231,9 +268,13 @@ static bool writeSettingsToEEPROM(void)
         if (pgIsSystem(reg)) {
             // write the only instance
             record.flags |= CR_CLASSICATION_SYSTEM;
-            config_streamer_write(&streamer, (uint8_t *)&record, sizeof(record));
+            if (config_streamer_write(&streamer, (uint8_t *)&record, sizeof(record)) < 0) {
+                return false;
+            }
             crc = updateCRC(crc, (uint8_t *)&record, sizeof(record));
-            config_streamer_write(&streamer, reg->address, regSize);
+            if (config_streamer_write(&streamer, reg->address, regSize) < 0) {
+                return false;
+            }
             crc = updateCRC(crc, reg->address, regSize);
         } else {
             // write one instance for each profile
@@ -241,10 +282,14 @@ static bool writeSettingsToEEPROM(void)
                 record.flags = 0;
 
                 record.flags |= ((profileIndex + 1) & CR_CLASSIFICATION_MASK);
-                config_streamer_write(&streamer, (uint8_t *)&record, sizeof(record));
+                if (config_streamer_write(&streamer, (uint8_t *)&record, sizeof(record)) < 0) {
+                    return false;
+                }
                 crc = updateCRC(crc, (uint8_t *)&record, sizeof(record));
                 const uint8_t *address = reg->address + (regSize * profileIndex);
-                config_streamer_write(&streamer, address, regSize);
+                if (config_streamer_write(&streamer, address, regSize) < 0) {
+                    return false;
+                }
                 crc = updateCRC(crc, address, regSize);
             }
         }
@@ -254,13 +299,19 @@ static bool writeSettingsToEEPROM(void)
         .terminator = 0,
     };
 
-    config_streamer_write(&streamer, (uint8_t *)&footer, sizeof(footer));
+    if (config_streamer_write(&streamer, (uint8_t *)&footer, sizeof(footer)) < 0) {
+        return false;
+    }
     crc = updateCRC(crc, (uint8_t *)&footer, sizeof(footer));
 
     // append checksum now
-    config_streamer_write(&streamer, (uint8_t *)&crc, sizeof(crc));
+    if (config_streamer_write(&streamer, (uint8_t *)&crc, sizeof(crc)) < 0) {
+        return false;
+    }
 
-    config_streamer_flush(&streamer);
+    if (config_streamer_flush(&streamer) < 0) {
+        return false;
+    }
 
     bool success = config_streamer_finish(&streamer) == 0;
 
@@ -274,6 +325,10 @@ void writeConfigToEEPROM(void)
     for (int attempt = 0; attempt < 3 && !success; attempt++) {
         if (writeSettingsToEEPROM()) {
             success = true;
+#ifdef CONFIG_IN_EXTERNAL_FLASH
+            // copy it back from flash to the in-memory buffer.
+            success = loadEEPROMFromExternalFlash();
+#endif
         }
     }
 
diff --git a/src/main/config/config_streamer.c b/src/main/config/config_streamer.c
index c09bac00dd..6a598cc9e4 100644
--- a/src/main/config/config_streamer.c
+++ b/src/main/config/config_streamer.c
@@ -19,6 +19,11 @@
 #include "platform.h"
 #include "drivers/system.h"
 #include "config/config_streamer.h"
+#include "build/build_config.h"
+
+#if !defined(CONFIG_IN_FLASH)
+SLOW_RAM uint8_t eepromData[EEPROM_SIZE];
+#endif
 
 // Helper functions
 extern void config_streamer_impl_unlock(void);
@@ -35,6 +40,7 @@ void config_streamer_start(config_streamer_t *c, uintptr_t base, int size)
     // base must start at FLASH_PAGE_SIZE boundary when using embedded flash.
     c->address = base;
     c->size = size;
+    c->end = base + size;
     if (!c->unlocked) {
         config_streamer_impl_unlock();
         c->unlocked = true;
@@ -44,6 +50,11 @@ void config_streamer_start(config_streamer_t *c, uintptr_t base, int size)
 
 int config_streamer_write(config_streamer_t *c, const uint8_t *p, uint32_t size)
 {
+    if ((c->address + size) > c->end) {
+        // trying to write past end of streamer
+        return -1;
+    }
+
     for (const uint8_t *pat = p; pat != (uint8_t*)p + size; pat++) {
         c->buffer.b[c->at++] = *pat;
 
@@ -63,6 +74,9 @@ int config_streamer_status(config_streamer_t *c)
 int config_streamer_flush(config_streamer_t *c)
 {
     if (c->at != 0) {
+        if ((c->address + c->at) > c->end) {
+            return -1;
+        }
         memset(c->buffer.b + c->at, 0, sizeof(c->buffer) - c->at);
         c->err = config_streamer_impl_write_word(c, &c->buffer.w);
         c->at = 0;
diff --git a/src/main/config/config_streamer.h b/src/main/config/config_streamer.h
index 952c811efe..87b688406f 100644
--- a/src/main/config/config_streamer.h
+++ b/src/main/config/config_streamer.h
@@ -20,10 +20,15 @@
 #include <stdint.h>
 #include <stdbool.h>
 
+#include "drivers/flash_m25p16.h"
+
 // Streams data out to the EEPROM, padding to the write size as
 // needed, and updating the checksum as it goes.
 
-#if defined(STM32H7)
+#ifdef CONFIG_IN_EXTERNAL_FLASH
+#define CONFIG_STREAMER_BUFFER_SIZE M25P16_PAGESIZE // Must match flash device page size
+typedef uint32_t config_streamer_buffer_align_type_t;
+#elif defined(STM32H7)
 #define CONFIG_STREAMER_BUFFER_SIZE 32  // Flash word = 256-bits
 typedef uint64_t config_streamer_buffer_align_type_t;
 #else
@@ -33,6 +38,7 @@ typedef uint32_t config_streamer_buffer_align_type_t;
 
 typedef struct config_streamer_s {
     uintptr_t address;
+    uintptr_t end;
     int size;
     union {
         uint8_t b[CONFIG_STREAMER_BUFFER_SIZE];
diff --git a/src/main/config/config_streamer_extflash.c b/src/main/config/config_streamer_extflash.c
new file mode 100644
index 0000000000..cb576ccc26
--- /dev/null
+++ b/src/main/config/config_streamer_extflash.c
@@ -0,0 +1,77 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include "platform.h"
+#include "drivers/system.h"
+#include "drivers/flash.h"
+#include "config/config_streamer.h"
+
+#if defined(CONFIG_IN_EXTERNAL_FLASH)
+
+static bool streamerLocked = true;
+
+void config_streamer_impl_unlock(void)
+{
+    const flashGeometry_t *flashGeometry = flashGetGeometry();
+    if (flashGeometry->pageSize == CONFIG_STREAMER_BUFFER_SIZE) {
+        // streamer needs to buffer exactly one flash page
+        streamerLocked = false;
+    }
+}
+
+void config_streamer_impl_lock(void)
+{
+    streamerLocked = true;
+}
+
+int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer_align_type_t *buffer)
+{
+    if (streamerLocked) {
+        return -1;
+    }
+
+    uint32_t dataOffset = (uint32_t)(c->address - (uintptr_t)&eepromData[0]);
+
+    const flashPartition_t *flashPartition = flashPartitionFindByType(FLASH_PARTITION_TYPE_CONFIG);
+    const flashGeometry_t *flashGeometry = flashGetGeometry();
+
+    uint32_t flashStartAddress = flashPartition->startSector * flashGeometry->sectorSize;
+    uint32_t flashOverflowAddress = ((flashPartition->endSector + 1) * flashGeometry->sectorSize); // +1 to sector for inclusive
+
+    uint32_t flashAddress = flashStartAddress + dataOffset;
+    if (flashAddress + CONFIG_STREAMER_BUFFER_SIZE > flashOverflowAddress) {
+        return -2; // address is past end of partition
+    }
+
+    uint32_t flashSectorSize = flashGeometry->sectorSize;
+
+    if (flashAddress % flashSectorSize == 0) {
+        flashEraseSector(flashAddress);
+    }
+
+    if (flashPageProgram(flashAddress, (uint8_t *)buffer, CONFIG_STREAMER_BUFFER_SIZE) == flashAddress) {
+        // returned same address: programming failed
+        return -3;
+    }
+
+    c->address += CONFIG_STREAMER_BUFFER_SIZE;
+
+    return 0;
+}
+
+#endif
diff --git a/src/main/config/config_streamer_ram.c b/src/main/config/config_streamer_ram.c
new file mode 100644
index 0000000000..9a7e8578ab
--- /dev/null
+++ b/src/main/config/config_streamer_ram.c
@@ -0,0 +1,61 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include "platform.h"
+#include "drivers/system.h"
+#include "config/config_streamer.h"
+
+#if defined(CONFIG_IN_RAM)
+
+static bool streamerLocked = true;
+
+void config_streamer_impl_unlock(void)
+{
+    streamerLocked = false;
+}
+
+void config_streamer_impl_lock(void)
+{
+    streamerLocked = true;
+}
+
+int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer_align_type_t *buffer)
+{
+    if (streamerLocked) {
+        return -1;
+    }
+
+    if (c->address == (uintptr_t)&eepromData[0]) {
+        memset(eepromData, 0, sizeof(eepromData));
+    }
+
+    config_streamer_buffer_align_type_t *destAddr = (config_streamer_buffer_align_type_t *)c->address;
+    config_streamer_buffer_align_type_t *srcAddr = buffer;
+
+    uint8_t nRows = CONFIG_STREAMER_BUFFER_SIZE / sizeof(config_streamer_buffer_align_type_t);
+
+    do {
+        *destAddr++ = *srcAddr++;
+    } while(--nRows != 0);
+
+    c->address += CONFIG_STREAMER_BUFFER_SIZE;
+
+    return 0;
+}
+
+#endif
diff --git a/src/main/config/config_streamer_stm32f3.c b/src/main/config/config_streamer_stm32f3.c
index 41c49d22b6..f56f86e7a9 100644
--- a/src/main/config/config_streamer_stm32f3.c
+++ b/src/main/config/config_streamer_stm32f3.c
@@ -20,7 +20,7 @@
 #include "drivers/system.h"
 #include "config/config_streamer.h"
 
-#if defined(STM32F3)
+#if defined(STM32F3) && !defined(CONFIG_IN_RAM) && !defined(CONFIG_IN_EXTERNAL_FLASH)
 
 #define FLASH_PAGE_SIZE     0x800
 
@@ -57,4 +57,4 @@ int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer
     return 0;
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/main/config/config_streamer_stm32f4.c b/src/main/config/config_streamer_stm32f4.c
index dcd7b5feab..4f48831bc8 100644
--- a/src/main/config/config_streamer_stm32f4.c
+++ b/src/main/config/config_streamer_stm32f4.c
@@ -20,7 +20,7 @@
 #include "drivers/system.h"
 #include "config/config_streamer.h"
 
-#if defined(STM32F4)
+#if defined(STM32F4) && !defined(CONFIG_IN_RAM) && !defined(CONFIG_IN_EXTERNAL_FLASH)
 
 /*
 Sector 0    0x08000000 - 0x08003FFF 16 Kbytes
@@ -103,4 +103,4 @@ int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer
     return 0;
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/main/config/config_streamer_stm32f7.c b/src/main/config/config_streamer_stm32f7.c
index afcedc7ba0..61b148fce5 100644
--- a/src/main/config/config_streamer_stm32f7.c
+++ b/src/main/config/config_streamer_stm32f7.c
@@ -20,7 +20,7 @@
 #include "drivers/system.h"
 #include "config/config_streamer.h"
 
-#if defined(STM32F7)
+#if defined(STM32F7) && !defined(CONFIG_IN_RAM) && !defined(CONFIG_IN_EXTERNAL_FLASH)
 
 #if defined(STM32F745xx) || defined(STM32F746xx) || defined(STM32F765xx)
 /*
@@ -138,4 +138,4 @@ int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer
     return 0;    
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/main/config/config_streamer_stm32h7.c b/src/main/config/config_streamer_stm32h7.c
index ee23ada22c..baa41ea92b 100644
--- a/src/main/config/config_streamer_stm32h7.c
+++ b/src/main/config/config_streamer_stm32h7.c
@@ -20,7 +20,7 @@
 #include "drivers/system.h"
 #include "config/config_streamer.h"
 
-#if defined(STM32H7)
+#if defined(STM32H7) && !defined(CONFIG_IN_RAM) && !defined(CONFIG_IN_EXTERNAL_FLASH)
 
 #if defined(STM32H743xx)
 /* Sectors 0-7 of 128K each */
@@ -96,4 +96,4 @@ int config_streamer_impl_write_word(config_streamer_t *c, config_streamer_buffer
     return 0;
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/main/drivers/flash.c b/src/main/drivers/flash.c
index f65c1fd497..647ac675a0 100644
--- a/src/main/drivers/flash.c
+++ b/src/main/drivers/flash.c
@@ -196,7 +196,15 @@ static void flashConfigurePartitions(void)
 #endif
 
 #if defined(CONFIG_IN_EXTERNAL_FLASH)
-    createPartition(FLASH_PARTITION_TYPE_CONFIG, EEPROM_SIZE, &endSector);
+    uint32_t configSize = EEPROM_SIZE;
+    flashSector_t configSectors = (configSize / flashGeometry->sectorSize);
+
+    if (configSize % flashGeometry->sectorSize > 0) {
+        configSectors++; // needs a portion of a sector.
+    }
+    configSize = configSectors * flashGeometry->sectorSize;
+
+    createPartition(FLASH_PARTITION_TYPE_CONFIG, configSize, &endSector);
 #endif
 
 #ifdef USE_FLASHFS
diff --git a/src/main/drivers/flash_m25p16.c b/src/main/drivers/flash_m25p16.c
index c2529b436b..ea22ffddde 100644
--- a/src/main/drivers/flash_m25p16.c
+++ b/src/main/drivers/flash_m25p16.c
@@ -68,6 +68,7 @@ static flashGeometry_t geometry = {.pageSize = M25P16_PAGESIZE};
 
 static busDevice_t * busDev = NULL;
 static bool isLargeFlash = false;
+static uint32_t timeoutAt = 0;
 
 /*
  * Whether we've performed an action that could have made the device busy for writes.
@@ -114,15 +115,30 @@ bool m25p16_isReady(void)
     return !couldBeBusy;
 }
 
+static void m25p16_setTimeout(uint32_t timeoutMillis)
+{
+    uint32_t now = millis();
+    timeoutAt = now + timeoutMillis;
+}
+
 bool m25p16_waitForReady(uint32_t timeoutMillis)
 {
-    uint32_t time = millis();
+    uint32_t timeoutAtUse;
+    if (timeoutMillis == 0) {
+        timeoutAtUse = timeoutAt;
+    }
+    else {
+        timeoutAtUse = millis() + timeoutMillis;
+    }
+
     while (!m25p16_isReady()) {
-        if (timeoutMillis && (millis() - time > timeoutMillis)) {
+        uint32_t now = millis();
+        if (now >= timeoutAtUse) {
             return false;
         }
     }
 
+    timeoutAt = 0;
     return true;
 }
 
@@ -216,10 +232,6 @@ static bool m25p16_readIdentification(void)
  */
 bool m25p16_init(int flashNumToUse)
 {
-    if (busDev) {
-        return true;
-    }
-
     busDev = busDeviceInit(BUSTYPE_SPI, DEVHW_M25P16, flashNumToUse, OWNER_FLASH);
     if (busDev == NULL) {
         return false;
@@ -252,20 +264,28 @@ void m25p16_eraseSector(uint32_t address)
 
     m25p16_setCommandAddress(&out[1], address, isLargeFlash);
 
-    m25p16_waitForReady(SECTOR_ERASE_TIMEOUT_MILLIS);
+    if (!m25p16_waitForReady(0)) {
+        return;
+    }
 
     m25p16_writeEnable();
 
     busTransfer(busDev, NULL, out, isLargeFlash ? 5 : 4);
+
+    m25p16_setTimeout(SECTOR_ERASE_TIMEOUT_MILLIS);
 }
 
 void m25p16_eraseCompletely(void)
 {
-    m25p16_waitForReady(BULK_ERASE_TIMEOUT_MILLIS);
+    if (!m25p16_waitForReady(0)) {
+        return;
+    }
 
     m25p16_writeEnable();
 
     m25p16_performOneByteCommand(M25P16_INSTRUCTION_BULK_ERASE);
+
+    m25p16_setTimeout(BULK_ERASE_TIMEOUT_MILLIS);
 }
 
 /**
@@ -294,12 +314,17 @@ uint32_t m25p16_pageProgram(uint32_t address, const uint8_t *data, int length)
 
     m25p16_setCommandAddress(&command[1], address, isLargeFlash);
 
-    m25p16_waitForReady(DEFAULT_TIMEOUT_MILLIS);
+    if (!m25p16_waitForReady(0)) {
+        // return same address to indicate timeout
+        return address;
+    }
 
     m25p16_writeEnable();
 
     busTransferMultiple(busDev, txn, 2);
 
+    m25p16_setTimeout(DEFAULT_TIMEOUT_MILLIS);
+
     return address + length;
 }
 
@@ -322,7 +347,7 @@ int m25p16_readBytes(uint32_t address, uint8_t *buffer, int length)
 
     m25p16_setCommandAddress(&command[1], address, isLargeFlash);
 
-    if (!m25p16_waitForReady(DEFAULT_TIMEOUT_MILLIS)) {
+    if (!m25p16_waitForReady(0)) {
         return 0;
     }
 
diff --git a/src/main/drivers/system.h b/src/main/drivers/system.h
index 2f2184613b..10c0a1e717 100644
--- a/src/main/drivers/system.h
+++ b/src/main/drivers/system.h
@@ -30,7 +30,8 @@ typedef enum {
     FAILURE_ACC_INCOMPATIBLE,
     FAILURE_INVALID_EEPROM_CONTENTS,
     FAILURE_FLASH_WRITE_FAILED,
-    FAILURE_GYRO_INIT_FAILED
+    FAILURE_GYRO_INIT_FAILED,
+    FAILURE_FLASH_READ_FAILED,
 } failureMode_e;
 
 // failure
diff --git a/src/main/fc/fc_init.c b/src/main/fc/fc_init.c
index 1250872995..a53d1088bc 100644
--- a/src/main/fc/fc_init.c
+++ b/src/main/fc/fc_init.c
@@ -217,6 +217,13 @@ void init(void)
     detectBrushedESC();
 #endif
 
+#ifdef CONFIG_IN_EXTERNAL_FLASH
+    // Reset config to defaults. Note: Default flash config must be functional for config in external flash to work.
+    pgResetAll(0);
+
+    flashDeviceInitialized = flashInit();
+#endif
+
     initEEPROM();
     ensureEEPROMContainsValidData();
     readEEPROM();
@@ -360,6 +367,11 @@ void init(void)
     // Initialize buses
     busInit();
 
+#ifdef CONFIG_IN_EXTERNAL_FLASH
+    // busInit re-configures the SPI pins. Init flash again so it is ready to write settings
+    flashDeviceInitialized = flashInit();
+#endif
+
 #ifdef USE_HARDWARE_REVISION_DETECTION
     updateHardwareRevision();
 #endif
diff --git a/src/main/fc/firmware_update_common.h b/src/main/fc/firmware_update_common.h
index 27fd8799e2..ce396875ad 100644
--- a/src/main/fc/firmware_update_common.h
+++ b/src/main/fc/firmware_update_common.h
@@ -39,8 +39,11 @@
 #define AVAILABLE_FIRMWARE_SPACE (FLASH_END - FIRMWARE_START_ADDRESS)
 
 extern uint8_t __firmware_start; // set via linker
+
+#if defined(CONFIG_IN_FLASH)
 extern uint8_t __config_start;
 extern uint8_t __config_end;
+#endif
 
 typedef struct {
     uint32_t magic;
diff --git a/src/main/target/common_post.h b/src/main/target/common_post.h
index 1fd40fcb44..0ca2ff4c9a 100644
--- a/src/main/target/common_post.h
+++ b/src/main/target/common_post.h
@@ -88,3 +88,18 @@ extern uint8_t __config_end;
 #define FILE_COMPILE_NORMAL
 #define FILE_COMPILE_FOR_SPEED
 #endif
+
+#if defined(CONFIG_IN_RAM) || defined(CONFIG_IN_EXTERNAL_FLASH)
+#ifndef EEPROM_SIZE
+#define EEPROM_SIZE     8192
+#endif
+extern uint8_t eepromData[EEPROM_SIZE];
+#define __config_start (*eepromData)
+#define __config_end (*ARRAYEND(eepromData))
+#else
+#ifndef CONFIG_IN_FLASH
+#define CONFIG_IN_FLASH
+#endif
+extern uint8_t __config_start;   // configured via linker script when building binaries.
+extern uint8_t __config_end;
+#endif
diff --git a/src/main/target/link/stm32_flash_h743xi.ld b/src/main/target/link/stm32_flash_h743xi.ld
index c338241bc7..7f3d857f5a 100644
--- a/src/main/target/link/stm32_flash_h743xi.ld
+++ b/src/main/target/link/stm32_flash_h743xi.ld
@@ -56,5 +56,6 @@ MEMORY
 
 REGION_ALIAS("STACKRAM", DTCM_RAM)
 REGION_ALIAS("FASTRAM",  DTCM_RAM)
+REGION_ALIAS("SLOWRAM",  D2_RAM)
 
 INCLUDE "stm32_flash_h7_split.ld"
\ No newline at end of file