diff --git a/libraries/technology/xaui/tech_xaui.vhd b/libraries/technology/xaui/tech_xaui.vhd
index 38eab5416bf40891e84f1956305628ca43e07ae1..4f0b80e066bf13c4dc2ac737acaedead6673dbd7 100644
--- a/libraries/technology/xaui/tech_xaui.vhd
+++ b/libraries/technology/xaui/tech_xaui.vhd
@@ -52,9 +52,11 @@ ENTITY tech_xaui IS
 
     a_rx_channelaligned     : OUT STD_LOGIC_VECTOR(g_nof_xaui-1 DOWNTO 0);
 
+    -- XGMII interface
     xgmii_tx_dc             : IN  t_xgmii_dc_arr(g_nof_xaui-1 DOWNTO 0);
     xgmii_rx_dc             : OUT t_xgmii_dc_arr(g_nof_xaui-1 DOWNTO 0);
 
+    -- Serial I/O
     xaui_rx                 : IN  t_xaui_arr(g_nof_xaui-1 DOWNTO 0);
     xaui_tx                 : OUT t_xaui_arr(g_nof_xaui-1 DOWNTO 0);