diff --git a/sources/decoding/FullToAxis.vhd b/sources/decoding/FullToAxis.vhd
index 168fcc1263b8a8d6b8cae9d42ef2896ed7a7f0b6..cae26a510300ed22174b48ad50bbfd89b2f3dd32 100644
--- a/sources/decoding/FullToAxis.vhd
+++ b/sources/decoding/FullToAxis.vhd
@@ -145,7 +145,7 @@ begin
       sop_found <= '0';
     elsif LinkAligned_240 = '1' then
       if FMdin(32) = '1' then
-        if FMdin(7 downto 0) = Kchar_sop and s_axis_tready = '1' then
+        if FMdin(31 downto 0) = (x"000000"&Kchar_sop) and s_axis_tready = '1' then
           sop_found <= '1';
         end if;
       end if;