diff --git a/rtic-monotonics/src/rp2040.rs b/rtic-monotonics/src/rp2040.rs
index b04376cc1740..a05dbf1b6fe4 100644
--- a/rtic-monotonics/src/rp2040.rs
+++ b/rtic-monotonics/src/rp2040.rs
@@ -50,7 +50,7 @@ impl TimerBackend {
     /// **Do not use this function directly.**
     ///
     /// Use the prelude macros instead.
-    pub fn _start(timer: TIMER, resets: &RESETS) {
+    pub fn _start(timer: TIMER, resets: &mut RESETS) {
         resets.reset().modify(|_, w| w.timer().clear_bit());
         while resets.reset_done().read().timer().bit_is_clear() {}
         timer.inte().modify(|_, w| w.alarm_0().bit(true));
diff --git a/rtic-monotonics/src/rp235x.rs b/rtic-monotonics/src/rp235x.rs
index 7624d1d9fcd1..ee8f6063a6b6 100644
--- a/rtic-monotonics/src/rp235x.rs
+++ b/rtic-monotonics/src/rp235x.rs
@@ -52,7 +52,7 @@ impl TimerBackend {
     /// **Do not use this function directly.**
     ///
     /// Use the prelude macros instead.
-    pub fn _start(timer: TIMER0, resets: &RESETS) {
+    pub fn _start(timer: TIMER0, resets: &mut RESETS) {
         resets.reset().modify(|_, w| w.timer0().clear_bit());
         while resets.reset_done().read().timer0().bit_is_clear() {}
         timer.inte().modify(|_, w| w.alarm_0().bit(true));