diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_Invensense.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_Invensense.cpp
index 55d798366b..61e45fe717 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_Invensense.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_Invensense.cpp
@@ -701,6 +701,7 @@ bool AP_InertialSensor_Invensense::_check_whoami(void)
         _mpu_type = Invensense_ICM20602;
         return true;
     case MPU_WHOAMI_ICM20789:
+    case MPU_WHOAMI_ICM20789_R1:
         _mpu_type = Invensense_ICM20789;
         return true;
     }
diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_Invensense_registers.h b/libraries/AP_InertialSensor/AP_InertialSensor_Invensense_registers.h
index c6424cb8b1..421fc1b79c 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_Invensense_registers.h
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_Invensense_registers.h
@@ -173,6 +173,7 @@
 #define MPU_WHOAMI_MPU9250      0x71
 #define MPU_WHOAMI_MPU9255      0x73
 #define MPU_WHOAMI_ICM20789     0x03
+#define MPU_WHOAMI_ICM20789_R1  0x02
 
 #define BIT_READ_FLAG                           0x80
 #define BIT_I2C_SLVX_EN                         0x80