diff --git a/conf/messages.xml b/conf/messages.xml
index cf25f32bc5..d4785486c4 100644
--- a/conf/messages.xml
+++ b/conf/messages.xml
@@ -1963,6 +1963,7 @@
     <field name="smbus_alert_cnt"             type="uint16"/>
     <field name="unexpected_event_cnt"        type="uint16"/>
     <field name="last_unexpected_event"       type="uint32"/>
+    <field name="bus_number"                  type="uint8"/>
   </message>
 
   <message name="RDYB_TRAJECTORY" id="254">
diff --git a/sw/airborne/boards/lisa_l/test_baro.c b/sw/airborne/boards/lisa_l/test_baro.c
index 124e9d2945..24985af985 100644
--- a/sw/airborne/boards/lisa_l/test_baro.c
+++ b/sw/airborne/boards/lisa_l/test_baro.c
@@ -87,6 +87,7 @@ static inline void main_periodic_task( void ) {
       uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
       uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
       uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
                                &i2c2_ack_fail_cnt,
                                &i2c2_miss_start_stop_cnt,
@@ -96,7 +97,8 @@ static inline void main_periodic_task( void ) {
                                &i2c2_timeout_tlow_cnt,
                                &i2c2_smbus_alert_cnt,
                                &i2c2_unexpected_event_cnt,
-                               &i2c2_last_unexpected_event);
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
 }
 
diff --git a/sw/airborne/boards/lisa_m/test_baro.c b/sw/airborne/boards/lisa_m/test_baro.c
index e77efaaed2..d0bba0376b 100644
--- a/sw/airborne/boards/lisa_m/test_baro.c
+++ b/sw/airborne/boards/lisa_m/test_baro.c
@@ -88,6 +88,7 @@ static inline void main_periodic_task( void ) {
       uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
       uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
       uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
                                &i2c2_ack_fail_cnt,
                                &i2c2_miss_start_stop_cnt,
@@ -97,7 +98,8 @@ static inline void main_periodic_task( void ) {
                                &i2c2_timeout_tlow_cnt,
                                &i2c2_smbus_alert_cnt,
                                &i2c2_unexpected_event_cnt,
-                               &i2c2_last_unexpected_event);
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
 }
 
diff --git a/sw/airborne/firmwares/rotorcraft/telemetry.h b/sw/airborne/firmwares/rotorcraft/telemetry.h
index 80502d42de..ace0a8d03d 100644
--- a/sw/airborne/firmwares/rotorcraft/telemetry.h
+++ b/sw/airborne/firmwares/rotorcraft/telemetry.h
@@ -751,6 +751,7 @@
     uint16_t i2c0_smbus_alert_cnt       = i2c0.errors->smbus_alert_cnt;       \
     uint16_t i2c0_unexpected_event_cnt  = i2c0.errors->unexpected_event_cnt;  \
     uint32_t i2c0_last_unexpected_event = i2c0.errors->last_unexpected_event; \
+    const uint8_t _bus0 = 0;                                            \
     DOWNLINK_SEND_I2C_ERRORS(_trans, _dev,                  \
                              &i2c0_ack_fail_cnt,            \
                              &i2c0_miss_start_stop_cnt,     \
@@ -760,7 +761,8 @@
                              &i2c0_timeout_tlow_cnt,        \
                              &i2c0_smbus_alert_cnt,         \
                              &i2c0_unexpected_event_cnt,    \
-                             &i2c0_last_unexpected_event);  \
+                             &i2c0_last_unexpected_event,   \
+                             &_bus0);                       \
   }
 #else
 #define PERIODIC_SEND_I2C0_ERRORS(_trans, _dev) {}
@@ -777,6 +779,7 @@
     uint16_t i2c1_smbus_alert_cnt       = i2c1.errors->smbus_alert_cnt;       \
     uint16_t i2c1_unexpected_event_cnt  = i2c1.errors->unexpected_event_cnt;  \
     uint32_t i2c1_last_unexpected_event = i2c1.errors->last_unexpected_event; \
+    const uint8_t _bus1 = 1;                                            \
     DOWNLINK_SEND_I2C_ERRORS(_trans, _dev,                  \
                              &i2c1_ack_fail_cnt,            \
                              &i2c1_miss_start_stop_cnt,     \
@@ -786,7 +789,8 @@
                              &i2c1_timeout_tlow_cnt,        \
                              &i2c1_smbus_alert_cnt,         \
                              &i2c1_unexpected_event_cnt,    \
-                             &i2c1_last_unexpected_event);  \
+                             &i2c1_last_unexpected_event,   \
+                             &_bus1);                       \
   }
 #else
 #define PERIODIC_SEND_I2C1_ERRORS(_trans, _dev) {}
@@ -803,6 +807,7 @@
     uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;       \
     uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;  \
     uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event; \
+    const uint8_t _bus2 = 2;                                            \
     DOWNLINK_SEND_I2C_ERRORS(_trans, _dev,                  \
                              &i2c2_ack_fail_cnt,            \
                              &i2c2_miss_start_stop_cnt,     \
@@ -812,7 +817,8 @@
                              &i2c2_timeout_tlow_cnt,        \
                              &i2c2_smbus_alert_cnt,         \
                              &i2c2_unexpected_event_cnt,    \
-                             &i2c2_last_unexpected_event);  \
+                             &i2c2_last_unexpected_event,   \
+                             &_bus2);                       \
   }
 #else
 #define PERIODIC_SEND_I2C2_ERRORS(_trans, _dev) {}
diff --git a/sw/airborne/lisa/test/lisa_test_hmc5843.c b/sw/airborne/lisa/test/lisa_test_hmc5843.c
index ca499b4092..38d85caecc 100644
--- a/sw/airborne/lisa/test/lisa_test_hmc5843.c
+++ b/sw/airborne/lisa/test/lisa_test_hmc5843.c
@@ -90,16 +90,27 @@ static inline void main_periodic_task( void ) {
   });
   RunOnceEvery(256,
     {
+      uint16_t i2c2_ack_fail_cnt          = i2c2.errors->ack_fail_cnt;
+      uint16_t i2c2_miss_start_stop_cnt   = i2c2.errors->miss_start_stop_cnt;
+      uint16_t i2c2_arb_lost_cnt          = i2c2.errors->arb_lost_cnt;
+      uint16_t i2c2_over_under_cnt        = i2c2.errors->over_under_cnt;
+      uint16_t i2c2_pec_recep_cnt         = i2c2.errors->pec_recep_cnt;
+      uint16_t i2c2_timeout_tlow_cnt      = i2c2.errors->timeout_tlow_cnt;
+      uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
+      uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
+      uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-			       &i2c2.errors->ack_fail_cnt,
-			       &i2c2.errors->miss_start_stop_cnt,
-			       &i2c2.errors->arb_lost_cnt,
-			       &i2c2.errors->over_under_cnt,
-			       &i2c2.errors->pec_recep_cnt,
-			       &i2c2.errors->timeout_tlow_cnt,
-			       &i2c2.errors->smbus_alert_cnt,
-			       &i2c2.errors->unexpected_event_cnt,
-			       &i2c2.errors->last_unexpected_event);
+                               &i2c2_ack_fail_cnt,
+                               &i2c2_miss_start_stop_cnt,
+                               &i2c2_arb_lost_cnt,
+                               &i2c2_over_under_cnt,
+                               &i2c2_pec_recep_cnt,
+                               &i2c2_timeout_tlow_cnt,
+                               &i2c2_smbus_alert_cnt,
+                               &i2c2_unexpected_event_cnt,
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
   if (mag_state == 2) send_config();
 
diff --git a/sw/airborne/lisa/test/lisa_test_itg3200.c b/sw/airborne/lisa/test/lisa_test_itg3200.c
index 72a66fac96..ccebfd903e 100644
--- a/sw/airborne/lisa/test/lisa_test_itg3200.c
+++ b/sw/airborne/lisa/test/lisa_test_itg3200.c
@@ -86,16 +86,27 @@ static inline void main_periodic_task( void ) {
     LED_PERIODIC();
   });
   RunOnceEvery(256, {
-   DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-			    &i2c2.errors->ack_fail_cnt,
-			    &i2c2.errors->miss_start_stop_cnt,
-			    &i2c2.errors->arb_lost_cnt,
-			    &i2c2.errors->over_under_cnt,
-			    &i2c2.errors->pec_recep_cnt,
-			    &i2c2.errors->timeout_tlow_cnt,
-			    &i2c2.errors->smbus_alert_cnt,
-			    &i2c2.errors->unexpected_event_cnt,
-			    &i2c2.errors->last_unexpected_event);
+      uint16_t i2c2_ack_fail_cnt          = i2c2.errors->ack_fail_cnt;
+      uint16_t i2c2_miss_start_stop_cnt   = i2c2.errors->miss_start_stop_cnt;
+      uint16_t i2c2_arb_lost_cnt          = i2c2.errors->arb_lost_cnt;
+      uint16_t i2c2_over_under_cnt        = i2c2.errors->over_under_cnt;
+      uint16_t i2c2_pec_recep_cnt         = i2c2.errors->pec_recep_cnt;
+      uint16_t i2c2_timeout_tlow_cnt      = i2c2.errors->timeout_tlow_cnt;
+      uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
+      uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
+      uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
+      DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
+                               &i2c2_ack_fail_cnt,
+                               &i2c2_miss_start_stop_cnt,
+                               &i2c2_arb_lost_cnt,
+                               &i2c2_over_under_cnt,
+                               &i2c2_pec_recep_cnt,
+                               &i2c2_timeout_tlow_cnt,
+                               &i2c2_smbus_alert_cnt,
+                               &i2c2_unexpected_event_cnt,
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
 
   switch (gyro_state) {
diff --git a/sw/airborne/lisa/test/test_board.c b/sw/airborne/lisa/test/test_board.c
index 7e01422dd3..6930867d69 100644
--- a/sw/airborne/lisa/test/test_board.c
+++ b/sw/airborne/lisa/test/test_board.c
@@ -155,16 +155,27 @@ static void test_baro_start(void) {all_led_green();}
 static void test_baro_periodic(void) {
   RunOnceEvery(2, {baro_periodic();});
   RunOnceEvery(100,{
+      uint16_t i2c2_ack_fail_cnt          = i2c2.errors->ack_fail_cnt;
+      uint16_t i2c2_miss_start_stop_cnt   = i2c2.errors->miss_start_stop_cnt;
+      uint16_t i2c2_arb_lost_cnt          = i2c2.errors->arb_lost_cnt;
+      uint16_t i2c2_over_under_cnt        = i2c2.errors->over_under_cnt;
+      uint16_t i2c2_pec_recep_cnt         = i2c2.errors->pec_recep_cnt;
+      uint16_t i2c2_timeout_tlow_cnt      = i2c2.errors->timeout_tlow_cnt;
+      uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
+      uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
+      uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-                   &i2c2.errors->ack_fail_cnt,
-                   &i2c2.errors->miss_start_stop_cnt,
-                   &i2c2.errors->arb_lost_cnt,
-                   &i2c2.errors->over_under_cnt,
-                   &i2c2.errors->pec_recep_cnt,
-                   &i2c2.errors->timeout_tlow_cnt,
-                   &i2c2.errors->smbus_alert_cnt,
-                   &i2c2.errors->unexpected_event_cnt,
-                   &i2c2.errors->last_unexpected_event);
+                               &i2c2_ack_fail_cnt,
+                               &i2c2_miss_start_stop_cnt,
+                               &i2c2_arb_lost_cnt,
+                               &i2c2_over_under_cnt,
+                               &i2c2_pec_recep_cnt,
+                               &i2c2_timeout_tlow_cnt,
+                               &i2c2_smbus_alert_cnt,
+                               &i2c2_unexpected_event_cnt,
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
 }
 static void test_baro_event(void) {BaroEvent(test_baro_on_baro_abs, test_baro_on_baro_diff);}
@@ -189,16 +200,27 @@ static void test_bldc_periodic(void) {
   i2c1_transmit(0x58, 1, NULL);
 
   RunOnceEvery(100,{
+      uint16_t i2c1_ack_fail_cnt          = i2c1.errors->ack_fail_cnt;
+      uint16_t i2c1_miss_start_stop_cnt   = i2c1.errors->miss_start_stop_cnt;
+      uint16_t i2c1_arb_lost_cnt          = i2c1.errors->arb_lost_cnt;
+      uint16_t i2c1_over_under_cnt        = i2c1.errors->over_under_cnt;
+      uint16_t i2c1_pec_recep_cnt         = i2c1.errors->pec_recep_cnt;
+      uint16_t i2c1_timeout_tlow_cnt      = i2c1.errors->timeout_tlow_cnt;
+      uint16_t i2c1_smbus_alert_cnt       = i2c1.errors->smbus_alert_cnt;
+      uint16_t i2c1_unexpected_event_cnt  = i2c1.errors->unexpected_event_cnt;
+      uint32_t i2c1_last_unexpected_event = i2c1.errors->last_unexpected_event;
+      const uint8_t _bus1 = 1;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-                   &i2c1.errors->ack_fail_cnt,
-                   &i2c1.errors->miss_start_stop_cnt,
-                   &i2c1.errors->arb_lost_cnt,
-                   &i2c1.errors->over_under_cnt,
-                   &i2c1.errors->pec_recep_cnt,
-                   &i2c1.errors->timeout_tlow_cnt,
-                   &i2c1.errors->smbus_alert_cnt,
-                   &i2c1.errors->unexpected_event_cnt,
-                   &i2c1.errors->last_unexpected_event);
+                               &i2c1_ack_fail_cnt,
+                               &i2c1_miss_start_stop_cnt,
+                               &i2c1_arb_lost_cnt,
+                               &i2c1_over_under_cnt,
+                               &i2c1_pec_recep_cnt,
+                               &i2c1_timeout_tlow_cnt,
+                               &i2c1_smbus_alert_cnt,
+                               &i2c1_unexpected_event_cnt,
+                               &i2c1_last_unexpected_event,
+                               &_bus1);
     });
 }
 
diff --git a/sw/airborne/lisa/test/test_mc_asctec_v1_simple.c b/sw/airborne/lisa/test/test_mc_asctec_v1_simple.c
index 2fcb0a9e07..2a2335bf71 100644
--- a/sw/airborne/lisa/test/test_mc_asctec_v1_simple.c
+++ b/sw/airborne/lisa/test/test_mc_asctec_v1_simple.c
@@ -64,16 +64,27 @@ static inline void main_periodic_task( void ) {
   RunOnceEvery(256, {DOWNLINK_SEND_ALIVE(DefaultChannel, DefaultDevice, 16, MD5SUM);});
   RunOnceEvery(256,
     {
+      uint16_t i2c1_ack_fail_cnt          = i2c1.errors->ack_fail_cnt;
+      uint16_t i2c1_miss_start_stop_cnt   = i2c1.errors->miss_start_stop_cnt;
+      uint16_t i2c1_arb_lost_cnt          = i2c1.errors->arb_lost_cnt;
+      uint16_t i2c1_over_under_cnt        = i2c1.errors->over_under_cnt;
+      uint16_t i2c1_pec_recep_cnt         = i2c1.errors->pec_recep_cnt;
+      uint16_t i2c1_timeout_tlow_cnt      = i2c1.errors->timeout_tlow_cnt;
+      uint16_t i2c1_smbus_alert_cnt       = i2c1.errors->smbus_alert_cnt;
+      uint16_t i2c1_unexpected_event_cnt  = i2c1.errors->unexpected_event_cnt;
+      uint32_t i2c1_last_unexpected_event = i2c1.errors->last_unexpected_event;
+      const uint8_t _bus1 = 1;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-			       &i2c1_errors.ack_fail_cnt,
-			       &i2c1_errors.miss_start_stop_cnt,
-			       &i2c1_errors.arb_lost_cnt,
-			       &i2c1_errors.over_under_cnt,
-			       &i2c1_errors.pec_recep_cnt,
-			       &i2c1_errors.timeout_tlow_cnt,
-			       &i2c1_errors.smbus_alert_cnt,
-			       &i2c1_errors.unexpected_event_cnt,
-			       &i2c1_errors.last_unexpected_event);
+                               &i2c1_ack_fail_cnt,
+                               &i2c1_miss_start_stop_cnt,
+                               &i2c1_arb_lost_cnt,
+                               &i2c1_over_under_cnt,
+                               &i2c1_pec_recep_cnt,
+                               &i2c1_timeout_tlow_cnt,
+                               &i2c1_smbus_alert_cnt,
+                               &i2c1_unexpected_event_cnt,
+                               &i2c1_last_unexpected_event,
+                               &_bus1);
     });
 
 
diff --git a/sw/airborne/test/subsystems/test_ahrs.c b/sw/airborne/test/subsystems/test_ahrs.c
index 2bb6d1b67b..5690ba6fa6 100644
--- a/sw/airborne/test/subsystems/test_ahrs.c
+++ b/sw/airborne/test/subsystems/test_ahrs.c
@@ -161,16 +161,27 @@ static inline void main_report(void) {
 		       },
 		       {
 #ifdef USE_I2C2
-			 DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-						  &i2c2.errors->ack_fail_cnt,
-						  &i2c2.errors->miss_start_stop_cnt,
-						  &i2c2.errors->arb_lost_cnt,
-						  &i2c2.errors->over_under_cnt,
-						  &i2c2.errors->pec_recep_cnt,
-						  &i2c2.errors->timeout_tlow_cnt,
-						  &i2c2.errors->smbus_alert_cnt,
-						  &i2c2.errors->unexpected_event_cnt,
-						  &i2c2.errors->last_unexpected_event);
+                 uint16_t i2c2_ack_fail_cnt          = i2c2.errors->ack_fail_cnt;
+                 uint16_t i2c2_miss_start_stop_cnt   = i2c2.errors->miss_start_stop_cnt;
+                 uint16_t i2c2_arb_lost_cnt          = i2c2.errors->arb_lost_cnt;
+                 uint16_t i2c2_over_under_cnt        = i2c2.errors->over_under_cnt;
+                 uint16_t i2c2_pec_recep_cnt         = i2c2.errors->pec_recep_cnt;
+                 uint16_t i2c2_timeout_tlow_cnt      = i2c2.errors->timeout_tlow_cnt;
+                 uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
+                 uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
+                 uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+                 const uint8_t _bus2 = 2;
+                 DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
+                                          &i2c2_ack_fail_cnt,
+                                          &i2c2_miss_start_stop_cnt,
+                                          &i2c2_arb_lost_cnt,
+                                          &i2c2_over_under_cnt,
+                                          &i2c2_pec_recep_cnt,
+                                          &i2c2_timeout_tlow_cnt,
+                                          &i2c2_smbus_alert_cnt,
+                                          &i2c2_unexpected_event_cnt,
+                                          &i2c2_last_unexpected_event,
+                                          &_bus2);
 #endif
 		       },
 		       {
diff --git a/sw/airborne/test/subsystems/test_imu.c b/sw/airborne/test/subsystems/test_imu.c
index b7f439bfb2..c56a30b7ff 100644
--- a/sw/airborne/test/subsystems/test_imu.c
+++ b/sw/airborne/test/subsystems/test_imu.c
@@ -82,16 +82,27 @@ static inline void main_periodic_task( void ) {
     });
 #ifdef USE_I2C2
   RunOnceEvery(111, {
+      uint16_t i2c2_ack_fail_cnt          = i2c2.errors->ack_fail_cnt;
+      uint16_t i2c2_miss_start_stop_cnt   = i2c2.errors->miss_start_stop_cnt;
+      uint16_t i2c2_arb_lost_cnt          = i2c2.errors->arb_lost_cnt;
+      uint16_t i2c2_over_under_cnt        = i2c2.errors->over_under_cnt;
+      uint16_t i2c2_pec_recep_cnt         = i2c2.errors->pec_recep_cnt;
+      uint16_t i2c2_timeout_tlow_cnt      = i2c2.errors->timeout_tlow_cnt;
+      uint16_t i2c2_smbus_alert_cnt       = i2c2.errors->smbus_alert_cnt;
+      uint16_t i2c2_unexpected_event_cnt  = i2c2.errors->unexpected_event_cnt;
+      uint32_t i2c2_last_unexpected_event = i2c2.errors->last_unexpected_event;
+      const uint8_t _bus2 = 2;
       DOWNLINK_SEND_I2C_ERRORS(DefaultChannel, DefaultDevice,
-                   &i2c2.errors->ack_fail_cnt,
-                   &i2c2.errors->miss_start_stop_cnt,
-                   &i2c2.errors->arb_lost_cnt,
-                   &i2c2.errors->over_under_cnt,
-                   &i2c2.errors->pec_recep_cnt,
-                   &i2c2.errors->timeout_tlow_cnt,
-                   &i2c2.errors->smbus_alert_cnt,
-                   &i2c2.errors->unexpected_event_cnt,
-                   &i2c2.errors->last_unexpected_event);
+                               &i2c2_ack_fail_cnt,
+                               &i2c2_miss_start_stop_cnt,
+                               &i2c2_arb_lost_cnt,
+                               &i2c2_over_under_cnt,
+                               &i2c2_pec_recep_cnt,
+                               &i2c2_timeout_tlow_cnt,
+                               &i2c2_smbus_alert_cnt,
+                               &i2c2_unexpected_event_cnt,
+                               &i2c2_last_unexpected_event,
+                               &_bus2);
     });
 #endif
   if (sys_time.nb_sec > 1) imu_periodic();