diff --git a/stmhal/main.c b/stmhal/main.c
index c674574575..ae4ff5141c 100644
--- a/stmhal/main.c
+++ b/stmhal/main.c
@@ -548,9 +548,8 @@ soft_reset:
     printf("PYB: sync filesystems\n");
     storage_flush();
 
-    timer_deinit();
-
     printf("PYB: soft reboot\n");
+    timer_deinit();
 
     first_soft_reset = false;
     goto soft_reset;
diff --git a/stmhal/timer.c b/stmhal/timer.c
index 8634c46bf2..73842e4b1d 100644
--- a/stmhal/timer.c
+++ b/stmhal/timer.c
@@ -107,6 +107,9 @@ static uint32_t tim3_counter = 0;
 STATIC pyb_timer_obj_t *pyb_timer_obj_all[14];
 #define PYB_TIMER_OBJ_ALL_NUM MP_ARRAY_SIZE(pyb_timer_obj_all)
 
+STATIC mp_obj_t pyb_timer_deinit(mp_obj_t self_in);
+STATIC mp_obj_t pyb_timer_callback(mp_obj_t self_in, mp_obj_t callback);
+
 void timer_init0(void) {
     tim3_counter = 0;
     for (uint i = 0; i < PYB_TIMER_OBJ_ALL_NUM; i++) {
@@ -114,6 +117,16 @@ void timer_init0(void) {
     }
 }
 
+// unregister all interrupt sources
+void timer_deinit(void) {
+    for (uint i = 0; i < PYB_TIMER_OBJ_ALL_NUM; i++) {
+        pyb_timer_obj_t *tim = pyb_timer_obj_all[i];
+        if (tim != NULL) {
+            pyb_timer_deinit(tim);
+        }
+    }
+}
+
 // TIM3 is set-up for the USB CDC interface
 void timer_tim3_init(void) {
     // set up the timer for USBD CDC
@@ -366,8 +379,6 @@ STATIC mp_obj_t pyb_timer_init(uint n_args, const mp_obj_t *args, mp_map_t *kw_a
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_timer_init_obj, 1, pyb_timer_init);
 
-STATIC mp_obj_t pyb_timer_callback(mp_obj_t self_in, mp_obj_t callback);
-
 /// \method deinit()
 /// Deinitialises the timer.
 ///
@@ -471,16 +482,6 @@ const mp_obj_type_t pyb_timer_type = {
     .locals_dict = (mp_obj_t)&pyb_timer_locals_dict,
 };
 
-// Unregister all interrupt sources
-void timer_deinit(void) {
-    for (uint i = 0; i < PYB_TIMER_OBJ_ALL_NUM; i++) {
-        pyb_timer_obj_t *tim = pyb_timer_obj_all[i];
-        if (tim != NULL) {
-            pyb_timer_deinit(tim);
-        }
-    }
-}
-
 void timer_irq_handler(uint tim_id) {
     if (tim_id - 1 < PYB_TIMER_OBJ_ALL_NUM) {
         // get the timer object