diff --git a/libraries/io/eth/src/vhdl/eth.vhd b/libraries/io/eth/src/vhdl/eth.vhd
index ee621ca7c0cb8753ab13f59dcde0643c25d5d1a2..06cc638d061c851aaf9dd7a312418f4018bdb766 100644
--- a/libraries/io/eth/src/vhdl/eth.vhd
+++ b/libraries/io/eth/src/vhdl/eth.vhd
@@ -635,7 +635,7 @@ BEGIN
   GENERIC MAP (
     g_technology   => g_technology,
     g_ETH_PHY      => g_ETH_PHY,
-    g_sim          => TRUE,
+    g_sim          => g_sim,
     g_sim_level    => g_sim_level,
     g_sim_tx       => TRUE,
     g_sim_rx       => sel_a_b(g_sim_level=1, FALSE, TRUE) -- TX only when using fast behavioural model