diff --git a/src/abfall.cpp b/src/abfall.cpp
index 002ee9a..e481c45 100644
--- a/src/abfall.cpp
+++ b/src/abfall.cpp
@@ -71,7 +71,7 @@ int main() {
 #endif
 
     while (true) {
-        auto timestamp = time_us_64() + 60000000ull;
+        auto timestamp = time_us_64() + 60'000'000ull;
 
         rtc_get_datetime(&dt);