--- a/targets/OSX/plc_OSX_main.c	Thu Nov 10 18:10:42 2022 +0800
+++ b/targets/OSX/plc_OSX_main.c	Thu Nov 10 23:21:22 2022 +0800
@@ -55,7 +55,7 @@
         dispatch_suspend(PLC_timer);
     } else {
         dispatch_time_t start;
-        start = dispatch_time(DISPATCH_TIME_NOW, next);
+        start = dispatch_walltime(NULL, next);
         dispatch_source_set_timer(PLC_timer, start, period, 0);
         dispatch_resume(PLC_timer);
     }