diff --git a/lib/emac/src/piso.vhd b/lib/emac/src/piso.vhd
index 966e769..7e5344f 100644
--- a/lib/emac/src/piso.vhd
+++ b/lib/emac/src/piso.vhd
@@ -62,7 +62,7 @@ begin
 end process;
 
 proc_fsm:
-process(state, din_vld, pre_fin)
+process(state, din_vld, shift_en, pre_fin)
 begin
 	state_next		<= state;
 	shift_reg_we	<= '0';
@@ -78,10 +78,12 @@ begin
 
 	when shift =>
 		if pre_fin = '1' then
-			din_re	<= din_vld;
 			if din_vld = '1' then
-				shift_reg_we	<= '1';
-				state_next		<= shift;
+				if shift_en = '1' then
+					din_re			<= '1';
+					shift_reg_we	<= '1';
+					state_next		<= shift;
+				end if;
 			else
 				state_next	<= idle;
 			end if;