diff --git a/Core/Src/main.c b/Core/Src/main.c
index 1d2cf4f..69c046c 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -91,6 +91,8 @@ int _write(int file, char *ptr, int len)
 
 void uart_debug_print(const char *fmt, ...)
 {
+  if (huart1.gState == HAL_UART_STATE_RESET) return;
+
   char buf[128];
   va_list args;