diff --git a/src/main/config/config.h b/src/main/config/config.h
index b45a7148e5..03abdd6e2d 100644
--- a/src/main/config/config.h
+++ b/src/main/config/config.h
@@ -47,10 +47,9 @@ typedef enum {
     FEATURE_TRANSPONDER = 1 << 21,
     FEATURE_AIRMODE = 1 << 22,
     FEATURE_SUPEREXPO_RATES = 1 << 23,
-    FEATURE_OSD = 1 << 24,
-    FEATURE_VTX = 1 << 25,
-    FEATURE_RX_NRF24 = 1 << 26,
-    FEATURE_SOFTSPI = 1 << 27,
+    FEATURE_VTX = 1 << 24,
+    FEATURE_RX_NRF24 = 1 << 25,
+    FEATURE_SOFTSPI = 1 << 26,
 } features_e;
 
 typedef enum {
diff --git a/src/main/drivers/accgyro_mpu6050.c b/src/main/drivers/accgyro_mpu6050.c
index 215a74cead..36caedddf7 100644
--- a/src/main/drivers/accgyro_mpu6050.c
+++ b/src/main/drivers/accgyro_mpu6050.c
@@ -1,4 +1,4 @@
-/*
+/*
  * This file is part of Cleanflight.
  *
  * Cleanflight is free software: you can redistribute it and/or modify
@@ -20,11 +20,10 @@
 #include <stdlib.h>
 
 #include "platform.h"
+
 #include "build/build_config.h"
-
 #include "build/debug.h"
 
-
 #include "common/maths.h"
 
 #include "nvic.h"
diff --git a/src/main/drivers/accgyro_mpu6500.c b/src/main/drivers/accgyro_mpu6500.c
index 984f168f1e..47deae1b8c 100644
--- a/src/main/drivers/accgyro_mpu6500.c
+++ b/src/main/drivers/accgyro_mpu6500.c
@@ -93,10 +93,15 @@ void mpu6500GyroInit(uint8_t lpf)
     mpuConfiguration.write(MPU_RA_PWR_MGMT_1, 0);
     delay(100);
     mpuConfiguration.write(MPU_RA_PWR_MGMT_1, INV_CLK_PLL);
+    delay(15);
     mpuConfiguration.write(MPU_RA_GYRO_CONFIG, INV_FSR_2000DPS << 3);
+    delay(15);
     mpuConfiguration.write(MPU_RA_ACCEL_CONFIG, INV_FSR_8G << 3);
+    delay(15);
     mpuConfiguration.write(MPU_RA_CONFIG, lpf);
+    delay(15);
     mpuConfiguration.write(MPU_RA_SMPLRT_DIV, gyroMPU6xxxCalculateDivider()); // Get Divider
+    delay(100);
 
     // Data ready interrupt configuration
 #ifdef USE_MPU9250_MAG
@@ -104,9 +109,7 @@ void mpu6500GyroInit(uint8_t lpf)
 #else
     mpuConfiguration.write(MPU_RA_INT_PIN_CFG, 0 << 7 | 0 << 6 | 0 << 5 | 1 << 4 | 0 << 3 | 0 << 2 | 0 << 1 | 0 << 0);  // INT_ANYRD_2CLEAR, BYPASS_EN
 #endif
-
 #ifdef USE_MPU_DATA_READY_SIGNAL
     mpuConfiguration.write(MPU_RA_INT_ENABLE, 0x01); // RAW_RDY_EN interrupt enable
 #endif
-
 }
diff --git a/src/main/drivers/accgyro_spi_mpu6000.c b/src/main/drivers/accgyro_spi_mpu6000.c
index fc00292503..925d0ea7b8 100644
--- a/src/main/drivers/accgyro_spi_mpu6000.c
+++ b/src/main/drivers/accgyro_spi_mpu6000.c
@@ -235,7 +235,7 @@ static void mpu6000AccAndGyroInit(void)
     // Accel Sample Rate 1kHz
     // Gyroscope Output Rate =  1kHz when the DLPF is enabled
     mpu6000WriteRegister(MPU_RA_SMPLRT_DIV, gyroMPU6xxxCalculateDivider());
-    delayMicroseconds(1);
+    delayMicroseconds(15);
 
     // Gyro +/- 1000 DPS Full Scale
     mpu6000WriteRegister(MPU_RA_GYRO_CONFIG, INV_FSR_2000DPS << 3);
diff --git a/src/main/drivers/accgyro_spi_mpu6500.c b/src/main/drivers/accgyro_spi_mpu6500.c
index 32ae6a1ce8..afc69fbf16 100755
--- a/src/main/drivers/accgyro_spi_mpu6500.c
+++ b/src/main/drivers/accgyro_spi_mpu6500.c
@@ -17,7 +17,6 @@
 
 #include <stdbool.h>
 #include <stdint.h>
-#include <stdlib.h>
 
 #include "platform.h"
 
diff --git a/src/main/drivers/accgyro_spi_mpu9250.c b/src/main/drivers/accgyro_spi_mpu9250.c
index c1fa690adb..d448caeb8a 100644
--- a/src/main/drivers/accgyro_spi_mpu9250.c
+++ b/src/main/drivers/accgyro_spi_mpu9250.c
@@ -27,7 +27,8 @@
 #include <stdint.h>
 
 #include "platform.h"
-#include "light_led.h"
+
+#include "build/debug.h"
 
 #include "common/axis.h"
 #include "common/maths.h"
@@ -38,8 +39,7 @@
 #include "exti.h"
 #include "bus_spi.h"
 #include "gyro_sync.h"
-#include "build/debug.h"
-
+#include "light_led.h"
 
 #include "sensor.h"
 #include "accgyro.h"
@@ -168,7 +168,7 @@ static void mpu9250AccAndGyroInit(uint8_t lpf) {
         verifympu9250WriteRegister(MPU_RA_CONFIG, 0); //8KHz, 250DLPF
     }
 
-    verifympu9250WriteRegister(MPU_RA_SMPLRT_DIV, gyroMPU6xxxGetDividerDrops()); // Get Divider Drops
+    verifympu9250WriteRegister(MPU_RA_SMPLRT_DIV, gyroMPU6xxxCalculateDivider()); // Get Divider Drops
 
     verifympu9250WriteRegister(MPU_RA_ACCEL_CONFIG, INV_FSR_8G << 3);
     verifympu9250WriteRegister(MPU_RA_INT_PIN_CFG, 0 << 7 | 0 << 6 | 0 << 5 | 1 << 4 | 0 << 3 | 0 << 2 | 1 << 1 | 0 << 0);  // INT_ANYRD_2CLEAR, BYPASS_EN
diff --git a/src/main/io/serial_cli.c b/src/main/io/serial_cli.c
index 4d21eac84c..36d438198d 100644
--- a/src/main/io/serial_cli.c
+++ b/src/main/io/serial_cli.c
@@ -199,7 +199,7 @@ static const char * const featureNames[] = {
     "SONAR", "TELEMETRY", "CURRENT_METER", "3D", "RX_PARALLEL_PWM",
     "RX_MSP", "RSSI_ADC", "LED_STRIP", "DISPLAY", "ONESHOT125",
     "BLACKBOX", "CHANNEL_FORWARDING", "TRANSPONDER", "AIRMODE",
-    "SUPEREXPO", "OSD", "VTX", "RX_NRF24", "SOFTSPI", NULL
+    "SUPEREXPO", "VTX", "RX_NRF24", "SOFTSPI", NULL
 };
 
 // sync this with rxFailsafeChannelMode_e
@@ -218,7 +218,7 @@ static const char * const sensorTypeNames[] = {
 
 #define SENSOR_NAMES_MASK (SENSOR_GYRO | SENSOR_ACC | SENSOR_BARO | SENSOR_MAG | SENSOR_SONAR)
 // sync with gyroSensor_e
-static const char * const gyroNames[] = { "", "None", "MPU6050", "L3G4200D", "MPU3050", "L3GD20", "MPU6000", "MPU6500", "FAKE"};
+static const char * const gyroNames[] = { "", "None", "MPU6050", "L3G4200D", "MPU3050", "L3GD20", "MPU6000", "MPU6500", "MPU9250", "FAKE"};
 // sync with accelerationSensor_e
 static const char * const accNames[] = { "None", "", "ADXL345", "MPU6050", "MMA845x", "BMA280", "LSM303DLHC", "MPU6000", "MPU6500", "FAKE"};
 // sync with baroSensor_e
@@ -415,7 +415,7 @@ static const char * const lookupTableNRF24RX[] = {
     "CX10",
     "CX10A",
     "H8_3D",
-    "REF"
+    "INAV"
 };
 #endif
 
diff --git a/src/main/io/serial_msp.c b/src/main/io/serial_msp.c
index 6a3b4b9fce..4c051b680d 100644
--- a/src/main/io/serial_msp.c
+++ b/src/main/io/serial_msp.c
@@ -1050,7 +1050,7 @@ static bool processOutCommand(uint8_t cmdMSP)
         break;
 
     case MSP_RX_CONFIG:
-        headSerialReply(17);
+        headSerialReply(21);
         serialize8(masterConfig.rxConfig.serialrx_provider);
         serialize16(masterConfig.rxConfig.maxcheck);
         serialize16(masterConfig.rxConfig.midrc);
@@ -1058,6 +1058,9 @@ static bool processOutCommand(uint8_t cmdMSP)
         serialize8(masterConfig.rxConfig.spektrum_sat_bind);
         serialize16(masterConfig.rxConfig.rx_min_usec);
         serialize16(masterConfig.rxConfig.rx_max_usec);
+        serialize8(0); // for compatibillity with betaflight
+        serialize8(0); // for compatibillity with betaflight
+        serialize16(0); // for compatibillity with betaflight
         serialize8(masterConfig.rxConfig.nrf24rx_protocol);
         serialize32(masterConfig.rxConfig.nrf24rx_id);
         break;
@@ -1589,9 +1592,15 @@ static bool processInCommand(void)
             masterConfig.rxConfig.rx_max_usec = read16();
         }
         if (currentPort->dataSize > 12) {
+            // for compatibility with betaflight
+            read8();
+            read8();
+            read16();
+        }
+        if (currentPort->dataSize > 16) {
             masterConfig.rxConfig.nrf24rx_protocol = read8();
         }
-        if (currentPort->dataSize > 13) {
+        if (currentPort->dataSize > 17) {
             masterConfig.rxConfig.nrf24rx_id = read32();
         }
         break;
diff --git a/src/main/rx/nrf24_inav.c b/src/main/rx/nrf24_inav.c
index e9831cfa99..157afbaaec 100644
--- a/src/main/rx/nrf24_inav.c
+++ b/src/main/rx/nrf24_inav.c
@@ -230,7 +230,7 @@ static void inavNrf24Setup(nrf24_protocol_t protocol, const uint32_t *nrf24rx_id
     UNUSED(protocol);
 
     NRF24L01_Initialize(BV(NRF24L01_00_CONFIG_EN_CRC) | BV( NRF24L01_00_CONFIG_CRCO)); // sets PWR_UP, EN_CRC, CRCO - 2 byte CRC
-    NRF24L01_Setup();
+    NRF24L01_SetupBasic();
 
     nrf24rxIdPtr = (uint32_t*)nrf24rx_id;
     if (nrf24rx_id == NULL || *nrf24rx_id == 0) {
diff --git a/src/main/sensors/gyro.h b/src/main/sensors/gyro.h
index e0559761ec..9f74e23e26 100644
--- a/src/main/sensors/gyro.h
+++ b/src/main/sensors/gyro.h
@@ -26,6 +26,7 @@ typedef enum {
     GYRO_L3GD20,
     GYRO_MPU6000,
     GYRO_MPU6500,
+    GYRO_MPU9250,
     GYRO_FAKE
 } gyroSensor_e;
 
diff --git a/src/main/sensors/initialisation.c b/src/main/sensors/initialisation.c
index 971a797132..60ea7d818e 100755
--- a/src/main/sensors/initialisation.c
+++ b/src/main/sensors/initialisation.c
@@ -22,7 +22,6 @@
 
 #include "build/build_config.h"
 
-
 #include "common/axis.h"
 
 #include "drivers/io.h"
@@ -46,6 +45,7 @@
 #include "drivers/bus_spi.h"
 #include "drivers/accgyro_spi_mpu6000.h"
 #include "drivers/accgyro_spi_mpu6500.h"
+#include "drivers/accgyro_spi_mpu9250.h"
 #include "drivers/gyro_sync.h"
 
 #include "drivers/barometer.h"
@@ -296,6 +296,20 @@ bool detectGyro(void)
 #endif
             ; // fallthrough
 
+    case GYRO_MPU9250:
+#ifdef USE_GYRO_SPI_MPU9250
+
+        if (mpu9250SpiGyroDetect(&gyro))
+        {
+            gyroHardware = GYRO_MPU9250;
+#ifdef GYRO_MPU9250_ALIGN
+            gyroAlign = GYRO_MPU9250_ALIGN;
+#endif
+
+            break;
+        }
+#endif
+        ; // fallthrough
         case GYRO_FAKE:
 #ifdef USE_FAKE_GYRO
             if (fakeGyroDetect(&gyro)) {
diff --git a/src/main/target/CC3D/target.h b/src/main/target/CC3D/target.h
index c71a29b76a..3139fbb302 100644
--- a/src/main/target/CC3D/target.h
+++ b/src/main/target/CC3D/target.h
@@ -64,7 +64,7 @@
 #define MAG
 #define USE_MAG_HMC5883
 #define USE_MAG_AK8975
-#define USE_MAG_MAG3110
+//#define USE_MAG_MAG3110
 
 #define USE_VCP
 #define USE_UART1
@@ -85,7 +85,7 @@
 //#define USE_RX_V202
 #define USE_RX_CX10
 //#define USE_RX_H8_3D
-#define USE_RX_REF
+#define USE_RX_INAV
 #define NRF24_DEFAULT_PROTOCOL  NRF24RX_SYMA_X5C
 //#define NRF24_DEFAULT_PROTOCOL NRF24RX_V202_1M
 //#define NRF24_DEFAULT_PROTOCOL NRF24RX_H8_3D
@@ -190,7 +190,7 @@
 #undef SPEKTRUM_BIND
 
 #else
-#define TARGET_MOTOR_COUNT 6
+#define TARGET_MOTOR_COUNT 4
 #define DISABLE_UNCOMMON_MIXERS
 #endif //OPBL
 
diff --git a/src/main/target/CJMCU/target.h b/src/main/target/CJMCU/target.h
index 53568cd0ff..b1052e9e02 100644
--- a/src/main/target/CJMCU/target.h
+++ b/src/main/target/CJMCU/target.h
@@ -70,7 +70,7 @@
 #define USE_RX_NRF24
 #define USE_RX_CX10
 #define USE_RX_H8_3D
-#define USE_RX_REF
+#define USE_RX_INAV
 //#define USE_RX_SYMA
 //#define USE_RX_V202
 //#define NRF24_DEFAULT_PROTOCOL  NRF24RX_SYMA_X5C
diff --git a/src/main/target/NAZE/target.h b/src/main/target/NAZE/target.h
index c346b5173b..7b802adbde 100644
--- a/src/main/target/NAZE/target.h
+++ b/src/main/target/NAZE/target.h
@@ -142,7 +142,7 @@
 
 #define USE_RX_CX10
 #define USE_RX_H8_3D
-#define USE_RX_REF
+#define USE_RX_INAV
 //#define USE_RX_SYMA
 //#define USE_RX_V202
 //#define NRF24_DEFAULT_PROTOCOL  NRF24RX_SYMA_X5C