diff --git a/fpga/Principal.vhd b/fpga/Principal.vhd
index 35b0a5d..4895b42 100644
--- a/fpga/Principal.vhd
+++ b/fpga/Principal.vhd
@@ -21,9 +21,11 @@ entity Principal is
              FRONTECHO: in std_logic;
              BACKTRIGGER: out std_logic;
              BACKECHO: in std_logic;
+             ENAREF: out std_logic;
              ENA: out std_logic;
              IN1ENC: out std_logic;
              IN2: out std_logic;
+             ENBREF: out std_logic;
              ENB: out std_logic;
              IN3END: out std_logic;
              IN4: out std_logic
@@ -225,6 +227,7 @@ begin
                             data => enAd,
                             pulse => ENA
                         );
+    ENAREF <= '1';
 
     in1enCp : PWM port map (
                                clk => pwmClk,
@@ -238,6 +241,7 @@ begin
                             data => enBd,
                             pulse => ENB
                         );
+    ENBREF <= '1';
 
     in3enDp : PWM port map (
                                clk => pwmClk,
diff --git a/fpga/principal.ucf b/fpga/principal.ucf
index 1bf99d3..0f02f8a 100644
--- a/fpga/principal.ucf
+++ b/fpga/principal.ucf
@@ -38,24 +38,28 @@ NET "BACKTRIGGER" LOC = "P72" | IOSTANDARD = LVTTL ;
 NET "BACKECHO" LOC = "P73" | IOSTANDARD = LVTTL ;
 
 # IO<20>
-NET "ENA" LOC = "P5" | IOSTANDARD = LVTTL ;
+NET "ENAREF" LOC = "P5" | IOSTANDARD = LVTTL ;
 
 # IO<21>
-NET "IN1ENC" LOC = "P4" | IOSTANDARD = LVTTL ;
+NET "ENA" LOC = "P4" | IOSTANDARD = LVTTL ;
 
 # IO<22>
-NET "IN2" LOC = "P6" | IOSTANDARD = LVTTL ;
+NET "IN1ENC" LOC = "P6" | IOSTANDARD = LVTTL ;
 
 # IO<23>
-NET "ENB" LOC = "P98" | IOSTANDARD = LVTTL ;
+NET "IN2" LOC = "P98" | IOSTANDARD = LVTTL ;
 
 # IO<24>
-NET "IN3END" LOC = "P94" | IOSTANDARD = LVTTL ;
+NET "ENBREF" LOC = "P94" | IOSTANDARD = LVTTL ;
 
 # IO<25>
-NET "IN4" LOC = "P93" | IOSTANDARD = LVTTL ;
+NET "ENB" LOC = "P93" | IOSTANDARD = LVTTL ;
+
+# IO<26>
+NET "IN3END" LOC = "P90" | IOSTANDARD = LVTTL ;
+
+# IO<27>
+NET "IN4" LOC = "P89" | IOSTANDARD = LVTTL ;
 
-# NET "IO<26>" LOC = "P90" | IOSTANDARD = LVTTL ;
-# NET "IO<27>" LOC = "P89" | IOSTANDARD = LVTTL ;
 # NET "IO<28>" LOC = "P88" | IOSTANDARD = LVTTL ;
 # NET "IO<29>" LOC = "P86" | IOSTANDARD = LVTTL ;