diff --git a/ports/stm32/Makefile b/ports/stm32/Makefile
index 31597e88a5..153ea44626 100644
--- a/ports/stm32/Makefile
+++ b/ports/stm32/Makefile
@@ -92,6 +92,7 @@ CFLAGS += -fsingle-precision-constant -Wdouble-promotion
 endif
 
 LDFLAGS = -nostdlib -L $(LD_DIR) $(addprefix -T,$(LD_FILES)) -Map=$(@:.elf=.map) --cref
+LDFLAGS += --defsym=_estack_reserve=8
 LIBS = $(shell $(CC) $(CFLAGS) -print-libgcc-file-name)
 
 # Remove uncalled code from the final image.
diff --git a/ports/stm32/boards/PYBD_SF2/f722_qspi.ld b/ports/stm32/boards/PYBD_SF2/f722_qspi.ld
index e9d6fa3c39..b6d3e08e30 100644
--- a/ports/stm32/boards/PYBD_SF2/f722_qspi.ld
+++ b/ports/stm32/boards/PYBD_SF2/f722_qspi.ld
@@ -31,7 +31,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K;
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/PYBD_SF6/f767.ld b/ports/stm32/boards/PYBD_SF6/f767.ld
index 2a474fba07..1dd4c11ed9 100644
--- a/ports/stm32/boards/PYBD_SF6/f767.ld
+++ b/ports/stm32/boards/PYBD_SF6/f767.ld
@@ -30,7 +30,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 24K;
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/STM32F769DISC/f769_qspi.ld b/ports/stm32/boards/STM32F769DISC/f769_qspi.ld
index 362fab3305..9a0bd56fb3 100644
--- a/ports/stm32/boards/STM32F769DISC/f769_qspi.ld
+++ b/ports/stm32/boards/STM32F769DISC/f769_qspi.ld
@@ -29,7 +29,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 32K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f091xc.ld b/ports/stm32/boards/stm32f091xc.ld
index 5e1e9e7bd3..5bcc4c7275 100644
--- a/ports/stm32/boards/stm32f091xc.ld
+++ b/ports/stm32/boards/stm32f091xc.ld
@@ -16,7 +16,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 6K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f401xd.ld b/ports/stm32/boards/stm32f401xd.ld
index 50cb3c571b..f4146abc6d 100644
--- a/ports/stm32/boards/stm32f401xd.ld
+++ b/ports/stm32/boards/stm32f401xd.ld
@@ -18,7 +18,7 @@ _minimum_heap_size = 16K; /* tunable */
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K;
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f401xe.ld b/ports/stm32/boards/stm32f401xe.ld
index 78e0dc1cba..e7bd8edfed 100644
--- a/ports/stm32/boards/stm32f401xe.ld
+++ b/ports/stm32/boards/stm32f401xe.ld
@@ -18,7 +18,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f405.ld b/ports/stm32/boards/stm32f405.ld
index 13133e8c6d..b6f5d30578 100644
--- a/ports/stm32/boards/stm32f405.ld
+++ b/ports/stm32/boards/stm32f405.ld
@@ -19,7 +19,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f411.ld b/ports/stm32/boards/stm32f411.ld
index 8ae5f6929c..50633118eb 100644
--- a/ports/stm32/boards/stm32f411.ld
+++ b/ports/stm32/boards/stm32f411.ld
@@ -18,7 +18,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f413xg.ld b/ports/stm32/boards/stm32f413xg.ld
index c2719b834f..96d6dc5fb0 100644
--- a/ports/stm32/boards/stm32f413xg.ld
+++ b/ports/stm32/boards/stm32f413xg.ld
@@ -21,7 +21,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f413xh.ld b/ports/stm32/boards/stm32f413xh.ld
index 017dbbac17..0b28730de5 100644
--- a/ports/stm32/boards/stm32f413xh.ld
+++ b/ports/stm32/boards/stm32f413xh.ld
@@ -21,7 +21,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f429.ld b/ports/stm32/boards/stm32f429.ld
index 35d0736eef..beeaa4df21 100644
--- a/ports/stm32/boards/stm32f429.ld
+++ b/ports/stm32/boards/stm32f429.ld
@@ -19,7 +19,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f439.ld b/ports/stm32/boards/stm32f439.ld
index 2b51c3a371..e847646b35 100644
--- a/ports/stm32/boards/stm32f439.ld
+++ b/ports/stm32/boards/stm32f439.ld
@@ -20,7 +20,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f722.ld b/ports/stm32/boards/stm32f722.ld
index 8986c68d52..ab41f0ea90 100644
--- a/ports/stm32/boards/stm32f722.ld
+++ b/ports/stm32/boards/stm32f722.ld
@@ -17,7 +17,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 32K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f746.ld b/ports/stm32/boards/stm32f746.ld
index 330dd97141..0f1de26964 100644
--- a/ports/stm32/boards/stm32f746.ld
+++ b/ports/stm32/boards/stm32f746.ld
@@ -19,7 +19,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f767.ld b/ports/stm32/boards/stm32f767.ld
index 47e992c2dd..9410b9fa6b 100644
--- a/ports/stm32/boards/stm32f767.ld
+++ b/ports/stm32/boards/stm32f767.ld
@@ -20,7 +20,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 32K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32f769.ld b/ports/stm32/boards/stm32f769.ld
index 41bb321a37..ebc6d033d9 100644
--- a/ports/stm32/boards/stm32f769.ld
+++ b/ports/stm32/boards/stm32f769.ld
@@ -19,7 +19,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 32K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32h743.ld b/ports/stm32/boards/stm32h743.ld
index 0f1c2b777e..69738ab8b9 100644
--- a/ports/stm32/boards/stm32h743.ld
+++ b/ports/stm32/boards/stm32h743.ld
@@ -19,7 +19,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32l432.ld b/ports/stm32/boards/stm32l432.ld
index 40515e75b3..5558b13c89 100644
--- a/ports/stm32/boards/stm32l432.ld
+++ b/ports/stm32/boards/stm32l432.ld
@@ -17,7 +17,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 6K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32l476xe.ld b/ports/stm32/boards/stm32l476xe.ld
index 330ec96e67..e4bcda1f16 100644
--- a/ports/stm32/boards/stm32l476xe.ld
+++ b/ports/stm32/boards/stm32l476xe.ld
@@ -20,7 +20,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32l476xg.ld b/ports/stm32/boards/stm32l476xg.ld
index 7983fb39a1..9fe83c74a4 100644
--- a/ports/stm32/boards/stm32l476xg.ld
+++ b/ports/stm32/boards/stm32l476xg.ld
@@ -20,7 +20,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM);
+_estack = ORIGIN(RAM) + LENGTH(RAM) - _estack_reserve;
 _sstack = _estack - 16K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/boards/stm32l496xg.ld b/ports/stm32/boards/stm32l496xg.ld
index e1ceb50707..c339903422 100644
--- a/ports/stm32/boards/stm32l496xg.ld
+++ b/ports/stm32/boards/stm32l496xg.ld
@@ -20,7 +20,7 @@ _minimum_heap_size = 16K;
 
 /* Define the stack.  The stack is full descending so begins just above last byte
    of RAM.  Note that EABI requires the stack to be 8-byte aligned for a call. */
-_estack = ORIGIN(RAM) + LENGTH(RAM) + LENGTH(SRAM2);
+_estack = ORIGIN(RAM) + LENGTH(RAM) + LENGTH(SRAM2) - _estack_reserve;
 _sstack = _estack - 206K; /* tunable */
 
 /* RAM extents for the garbage collector */
diff --git a/ports/stm32/main.c b/ports/stm32/main.c
index 523034e097..2dcc09ae7a 100644
--- a/ports/stm32/main.c
+++ b/ports/stm32/main.c
@@ -45,6 +45,7 @@
 
 #include "systick.h"
 #include "pendsv.h"
+#include "powerctrl.h"
 #include "pybthread.h"
 #include "gccollect.h"
 #include "factoryreset.h"
@@ -368,6 +369,9 @@ STATIC uint update_reset_mode(uint reset_mode) {
 #endif
 
 void stm32_main(uint32_t reset_mode) {
+    // Check if bootloader should be entered instead of main application
+    powerctrl_check_enter_bootloader();
+
     // Enable caches and prefetch buffers
 
     #if defined(STM32F4)
diff --git a/ports/stm32/modmachine.c b/ports/stm32/modmachine.c
index cf615ea6aa..a4ee47470b 100644
--- a/ports/stm32/modmachine.c
+++ b/ports/stm32/modmachine.c
@@ -237,7 +237,7 @@ MP_DEFINE_CONST_FUN_OBJ_0(machine_unique_id_obj, machine_unique_id);
 
 // Resets the pyboard in a manner similar to pushing the external RESET button.
 STATIC mp_obj_t machine_reset(void) {
-    NVIC_SystemReset();
+    powerctrl_mcu_reset();
     return mp_const_none;
 }
 MP_DEFINE_CONST_FUN_OBJ_0(machine_reset_obj, machine_reset);
@@ -248,15 +248,6 @@ STATIC mp_obj_t machine_soft_reset(void) {
 }
 MP_DEFINE_CONST_FUN_OBJ_0(machine_soft_reset_obj, machine_soft_reset);
 
-__attribute__((naked)) void branch_to_bootloader(uint32_t r0, uint32_t addr) {
-    __asm volatile (
-        "ldr r2, [r1, #0]\n"    // get address of stack pointer
-        "msr msp, r2\n"         // get stack pointer
-        "ldr r2, [r1, #4]\n"    // get address of destination
-        "bx r2\n"               // branch to bootloader
-    );
-}
-
 // Activate the bootloader without BOOT* pins.
 STATIC NORETURN mp_obj_t machine_bootloader(size_t n_args, const mp_obj_t *args) {
     #if MICROPY_HW_ENABLE_USB
@@ -266,24 +257,10 @@ STATIC NORETURN mp_obj_t machine_bootloader(size_t n_args, const mp_obj_t *args)
     storage_flush();
     #endif
 
-    #if __DCACHE_PRESENT == 1
-    // Flush and disable caches before turning off peripherals (eg SDRAM)
-    SCB_DisableICache();
-    SCB_DisableDCache();
-    #endif
-
-    HAL_RCC_DeInit();
-    HAL_DeInit();
-
-    #if (__MPU_PRESENT == 1)
-    // MPU must be disabled for bootloader to function correctly
-    HAL_MPU_Disable();
-    #endif
-
     #if MICROPY_HW_USES_BOOTLOADER
     if (n_args == 0 || !mp_obj_is_true(args[0])) {
         // By default, with no args given, we enter the custom bootloader (mboot)
-        branch_to_bootloader(0x70ad0000, 0x08000000);
+        powerctrl_enter_bootloader(0x70ad0000, 0x08000000);
     }
 
     if (n_args == 1 && mp_obj_is_str_or_bytes(args[0])) {
@@ -292,15 +269,14 @@ STATIC NORETURN mp_obj_t machine_bootloader(size_t n_args, const mp_obj_t *args)
         const char *data = mp_obj_str_get_data(args[0], &len);
         void *mboot_region = (void*)*((volatile uint32_t*)0x08000000);
         memmove(mboot_region, data, len);
-        branch_to_bootloader(0x70ad0080, 0x08000000);
+        powerctrl_enter_bootloader(0x70ad0080, 0x08000000);
     }
     #endif
 
     #if defined(STM32F7) || defined(STM32H7)
-    branch_to_bootloader(0, 0x1ff00000);
+    powerctrl_enter_bootloader(0, 0x1ff00000);
     #else
-    __HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
-    branch_to_bootloader(0, 0x00000000);
+    powerctrl_enter_bootloader(0, 0x00000000);
     #endif
 
     while (1);
diff --git a/ports/stm32/powerctrl.c b/ports/stm32/powerctrl.c
index c3792be3ed..2ad2426005 100644
--- a/ports/stm32/powerctrl.c
+++ b/ports/stm32/powerctrl.c
@@ -30,6 +30,60 @@
 #include "rtc.h"
 #include "genhdr/pllfreqtable.h"
 
+#if defined(STM32H7)
+#define RCC_SR          RSR
+#define RCC_SR_SFTRSTF  RCC_RSR_SFTRSTF
+#define RCC_SR_RMVF     RCC_RSR_RMVF
+#else
+#define RCC_SR          CSR
+#define RCC_SR_SFTRSTF  RCC_CSR_SFTRSTF
+#define RCC_SR_RMVF     RCC_CSR_RMVF
+#endif
+
+// Location in RAM of bootloader state (just after the top of the stack)
+extern uint32_t _estack[];
+#define BL_STATE ((uint32_t*)&_estack)
+
+NORETURN void powerctrl_mcu_reset(void) {
+    BL_STATE[1] = 1; // invalidate bootloader address
+    #if __DCACHE_PRESENT == 1
+    SCB_CleanDCache();
+    #endif
+    NVIC_SystemReset();
+}
+
+NORETURN void powerctrl_enter_bootloader(uint32_t r0, uint32_t bl_addr) {
+    BL_STATE[0] = r0;
+    BL_STATE[1] = bl_addr;
+    #if __DCACHE_PRESENT == 1
+    SCB_CleanDCache();
+    #endif
+    NVIC_SystemReset();
+}
+
+static __attribute__((naked)) void branch_to_bootloader(uint32_t r0, uint32_t bl_addr) {
+    __asm volatile (
+        "ldr r2, [r1, #0]\n"    // get address of stack pointer
+        "msr msp, r2\n"         // get stack pointer
+        "ldr r2, [r1, #4]\n"    // get address of destination
+        "bx r2\n"               // branch to bootloader
+    );
+}
+
+void powerctrl_check_enter_bootloader(void) {
+    uint32_t bl_addr = BL_STATE[1];
+    BL_STATE[1] = 1; // invalidate bootloader address
+    if ((bl_addr & 0xfff) == 0 && (RCC->RCC_SR & RCC_SR_SFTRSTF)) {
+        // Reset by NVIC_SystemReset with bootloader data set -> branch to bootloader
+        RCC->RCC_SR = RCC_SR_RMVF;
+        #if defined(STM32F0) || defined(STM32F4) || defined(STM32L4)
+        __HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
+        #endif
+        uint32_t r0 = BL_STATE[0];
+        branch_to_bootloader(r0, bl_addr);
+    }
+}
+
 #if !defined(STM32F0)
 
 // Assumes that PLL is used as the SYSCLK source
diff --git a/ports/stm32/powerctrl.h b/ports/stm32/powerctrl.h
index b26cab391c..6eb0342287 100644
--- a/ports/stm32/powerctrl.h
+++ b/ports/stm32/powerctrl.h
@@ -28,6 +28,10 @@
 
 #include <stdint.h>
 
+NORETURN void powerctrl_mcu_reset(void);
+NORETURN void powerctrl_enter_bootloader(uint32_t r0, uint32_t bl_addr);
+void powerctrl_check_enter_bootloader(void);
+
 int powerctrl_rcc_clock_config_pll(RCC_ClkInitTypeDef *rcc_init, uint32_t sysclk_mhz, bool need_pllsai);
 int powerctrl_set_sysclk(uint32_t sysclk, uint32_t ahb, uint32_t apb1, uint32_t apb2);
 void powerctrl_enter_stop_mode(void);
diff --git a/ports/stm32/stm32_it.c b/ports/stm32/stm32_it.c
index 0c5263e053..a3740d59cd 100644
--- a/ports/stm32/stm32_it.c
+++ b/ports/stm32/stm32_it.c
@@ -72,6 +72,7 @@
 #include "stm32_it.h"
 #include "pendsv.h"
 #include "irq.h"
+#include "powerctrl.h"
 #include "pybthread.h"
 #include "gccollect.h"
 #include "extint.h"
@@ -144,7 +145,7 @@ int pyb_hard_fault_debug = 0;
 
 void HardFault_C_Handler(ExceptionRegisters_t *regs) {
     if (!pyb_hard_fault_debug) {
-        NVIC_SystemReset();
+        powerctrl_mcu_reset();
     }
 
     #if MICROPY_HW_ENABLE_USB