diff --git a/src/sdc/scr1_core_top.sdc b/src/sdc/scr1_core_top.sdc
index 3cb2139..1689b65 100644
--- a/src/sdc/scr1_core_top.sdc
+++ b/src/sdc/scr1_core_top.sdc
@@ -28,7 +28,6 @@ set OUTPUT_DELAY_TCK      [expr $TCK_PERIOD/4.0]
 #clk->100MHz 
 create_clock -name "clk" -period $CLK_PERIOD -waveform "0 [expr $CLK_PERIOD/2.0]" [get_ports "clk"]
 
-#set_clock_groups -asynchronous -group {"clk"} -group {"tapc_tck"} -group {"rtc_clk"} 
 
 set MINRISE 0
 set MAXRISE 1.0