diff --git a/conf/modules/baro_ets.xml b/conf/modules/baro_ets.xml
index 9a8003de05..161637c126 100644
--- a/conf/modules/baro_ets.xml
+++ b/conf/modules/baro_ets.xml
@@ -11,11 +11,10 @@
   </header>
   <init fun="baro_ets_init()"/>
   <periodic fun="baro_ets_read_periodic()" freq="10."/>
-  <event fun="BaroEtsEvent()"/>
+  <event fun="baro_ets_event()"/>
 
   <makefile>
-    <file name="baro_ets.c"/> 
+    <file name="baro_ets.c"/>
   </makefile>
 
 </module>
-
diff --git a/sw/airborne/modules/sensors/baro_ets.c b/sw/airborne/modules/sensors/baro_ets.c
index 0d3064b11e..328b1e71f2 100644
--- a/sw/airborne/modules/sensors/baro_ets.c
+++ b/sw/airborne/modules/sensors/baro_ets.c
@@ -81,62 +81,65 @@ void baro_ets_init( void ) {
   baro_ets_cnt = BARO_ETS_OFFSET_NBSAMPLES_INIT + BARO_ETS_OFFSET_NBSAMPLES_AVRG;
   baro_ets_r = BARO_ETS_R;
   baro_ets_sigma2 = BARO_ETS_SIGMA2;
+
+  baro_ets_i2c_trans.status = I2CTransDone;
 }
 
 void baro_ets_read_periodic( void ) {
   // Initiate next read
 #ifndef SITL
-  I2CReceive(i2c0, baro_ets_i2c_trans, BARO_ETS_ADDR, 2);
+  if (baro_ets_i2c_trans.status == I2CTransDone)
+    I2CReceive(i2c0, baro_ets_i2c_trans, BARO_ETS_ADDR, 2);
 #else // SITL
   baro_ets_adc = 0;
   baro_ets_altitude = gps_alt / 100.0;
   baro_ets_valid = TRUE;
   EstimatorSetAlt(baro_ets_altitude);
 #endif
-}      
-        
-void baro_ets_read_event( void ) {
-  // Get raw altimeter from buffer
-  baro_ets_adc = ((uint16_t)(baro_ets_i2c_trans.buf[1]) << 8) | (uint16_t)(baro_ets_i2c_trans.buf[0]);
-  // Check if this is valid altimeter
-  if (baro_ets_adc == 0)
-    baro_ets_valid = FALSE;
-  else
-    baro_ets_valid = TRUE;
-
-  // Continue only if a new altimeter value was received  
-  if (baro_ets_valid) {
-    // Calculate offset average if not done already
-    if (!baro_ets_offset_init) {
-      --baro_ets_cnt;
-      // Check if averaging completed
-      if (baro_ets_cnt == 0) {
-        // Calculate average
-        baro_ets_offset = (uint16_t)(baro_ets_offset_tmp / BARO_ETS_OFFSET_NBSAMPLES_AVRG);
-        // Limit offset
-        if (baro_ets_offset < BARO_ETS_OFFSET_MIN)
-          baro_ets_offset = BARO_ETS_OFFSET_MIN;
-        if (baro_ets_offset > BARO_ETS_OFFSET_MAX)
-          baro_ets_offset = BARO_ETS_OFFSET_MAX;
-        baro_ets_offset_init = TRUE;
-      }
-      // Check if averaging needs to continue
-      else if (baro_ets_cnt <= BARO_ETS_OFFSET_NBSAMPLES_AVRG)
-        baro_ets_offset_tmp += baro_ets_adc;
-    }    
-    // Convert raw to m/s
-    if (baro_ets_offset_init)
-      baro_ets_altitude = BARO_ETS_SCALE * (float)(baro_ets_offset-baro_ets_adc);
-    else
-      baro_ets_altitude = 0.0;
-    // New value available
-    EstimatorSetAlt(baro_ets_altitude);
-  } else {
-    baro_ets_altitude = 0.0;
-  }
-
-  // Transaction has been read
-  baro_ets_i2c_trans.status = I2CTransDone;
-
 }
 
+void baro_ets_event( void ) {
+  if (baro_ets_i2c_trans.status == I2CTransSuccess) {
+    // Get raw altimeter from buffer
+    baro_ets_adc = ((uint16_t)(baro_ets_i2c_trans.buf[1]) << 8) | (uint16_t)(baro_ets_i2c_trans.buf[0]);
+    // Check if this is valid altimeter
+    if (baro_ets_adc == 0)
+      baro_ets_valid = FALSE;
+    else
+      baro_ets_valid = TRUE;
+
+    // Continue only if a new altimeter value was received
+    if (baro_ets_valid) {
+      // Calculate offset average if not done already
+      if (!baro_ets_offset_init) {
+        --baro_ets_cnt;
+        // Check if averaging completed
+        if (baro_ets_cnt == 0) {
+          // Calculate average
+          baro_ets_offset = (uint16_t)(baro_ets_offset_tmp / BARO_ETS_OFFSET_NBSAMPLES_AVRG);
+          // Limit offset
+          if (baro_ets_offset < BARO_ETS_OFFSET_MIN)
+            baro_ets_offset = BARO_ETS_OFFSET_MIN;
+          if (baro_ets_offset > BARO_ETS_OFFSET_MAX)
+            baro_ets_offset = BARO_ETS_OFFSET_MAX;
+          baro_ets_offset_init = TRUE;
+        }
+        // Check if averaging needs to continue
+        else if (baro_ets_cnt <= BARO_ETS_OFFSET_NBSAMPLES_AVRG)
+          baro_ets_offset_tmp += baro_ets_adc;
+      }
+      // Convert raw to m/s
+      if (baro_ets_offset_init)
+        baro_ets_altitude = BARO_ETS_SCALE * (float)(baro_ets_offset-baro_ets_adc);
+      else
+        baro_ets_altitude = 0.0;
+      // New value available
+      EstimatorSetAlt(baro_ets_altitude);
+    } else {
+      baro_ets_altitude = 0.0;
+    }
+
+    // Transaction has been read
+    baro_ets_i2c_trans.status = I2CTransDone;
+  }
+}
diff --git a/sw/airborne/modules/sensors/baro_ets.h b/sw/airborne/modules/sensors/baro_ets.h
index 337c4c041c..a288bcfbdf 100644
--- a/sw/airborne/modules/sensors/baro_ets.h
+++ b/sw/airborne/modules/sensors/baro_ets.h
@@ -56,8 +56,6 @@ extern struct i2c_transaction baro_ets_i2c_trans;
 
 extern void baro_ets_init( void );
 extern void baro_ets_read_periodic( void );
-extern void baro_ets_read_event( void );
-
-#define BaroEtsEvent() { if (baro_ets_i2c_trans.status == I2CTransSuccess) baro_ets_read_event(); }
+extern void baro_ets_event( void );
 
 #endif // BARO_ETS_H