diff --git a/Core/Src/rtc.c b/Core/Src/rtc.c
index a75fe36..b4073f9 100644
--- a/Core/Src/rtc.c
+++ b/Core/Src/rtc.c
@@ -46,7 +46,7 @@ void MX_RTC_Init(void)
   hrtc.Instance = RTC;
   hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
   hrtc.Init.AsynchPrediv = 127;
-  hrtc.Init.SynchPrediv = 255;
+  hrtc.Init.SynchPrediv = 249;
   hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
   hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
   hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;