diff --git a/df_datalink_sp/src/systembus/systembus.c b/df_datalink_sp/src/systembus/systembus.c
index 38c5397..30af524 100644
--- a/df_datalink_sp/src/systembus/systembus.c
+++ b/df_datalink_sp/src/systembus/systembus.c
@@ -367,11 +367,13 @@ int32_t SystemBus_HandleCmd(SYSBUS *instPtr)
 		}
 		else 
 		{
-			// FIXME: 
+			// FIXME: to confirm
 			// Halt linklayer
 			Linklayer_Halt(linkInstPtr);
 			DBG_ERROR("Unexpected config command 0x%02X:0x%02X", 
 				WD_MODE_CMD, data[WD_MODE_CMD]);
+			Status = EPARAM;
+			break;
 		}
 
 		if(data[WD_EN_CMD] == EN_CMD_ON_HIGH_POWER)