Set the Update Generation bit in order to reset counters, in particular the prescaler's, before starting the timer. Since it is set when Update Reset Source is set high no interrupt will be generated.

Author: osannolik

src/timer.rs

@@ -172,7 +172,11 @@ macro_rules! timers {
                         }
                     );
 
+                    // Load prescaler value and reset its counter.
+                    // Setting URS makes sure no interrupt is generated.
                     self.tim.cr1.modify(|_, w| w.urs().set_bit());
+                    self.tim.egr.write(|w| w.ug().set_bit());
+
                     self.tim.cr1.modify(|_, w| w.cen().set_bit());
                 }