Product name:20mmx20mm Happymodel CruxF405HD ELRS AIO 3in1 Flight Controller Built-in UART ELRS 2.4G RX 20A ESC for Toothpick / LR RC FPV Racing Drone Precise details: Introduction: The CruxF405HD ELRS AIO flight controller comes with integrated UART 2.4GHz ExpressLRS receiver and 20A Blheli_s ESC(Bluejay firmware pre-installed) which could support 2-4s battery. Bigger Mosfet could support high to 20A currents would be better for 2-4S toothpick drone or long range FPV drone. Reserved 6 pin socket for DJI HD equipment plug and play. It´s a great solution of build HD digital FPV drone . Specifications: Brand: Happymodel Model: CruxF405HD ELRS AIO Flight controller MCU: STM32F405RGT6 (168MHZ, 1Mbyte FLASH) GYRO Sensor: ICM42688 (SPI connection) Mount hole size: 20x20mm Power supply: 2~4S battery input (DC 8.7V-17.4V) Built-in 20A(each) Blheli_S 4in1 ESC Built-in Serial ExpressLRS 2.4G (Default connected to UART2) Built-in BMP280 Barometer Built-in 8MBp blackbox Built-in voltage meter sensor , voltage meter scale 110 Built-in current meter sensor , current meter scale 470 Flight controller firmware target: BETAFLIGHTF4 Onboard 4in1 ESC MCU upgraded to EFM8BB21 Power supply: 2-4S LiPo/LiPo HV (7v/17v) Currents: 20A continuous peak 25A (5 seconds) Support BLHeliSuite programmable Factory firmware: Bluejay 0.19.2 Firmware target: F_H_40_48_v0.19.2 Default protocol: DSHOT150/DSHOT300/DSHOT60 Onboard UART ExpressLRS 2.4GHz Receiver Packet Rate option: 25Hz/50Hz/150Hz/250Hz/500Hz RF Frequency: 2.4GHz Antenna plug: IPEX Telemetry output Power: Onboard voltage and Amperage meters settings Voltage meter scale setting 110 Amperage meter scale setting 470 Binding procedure: 1. Supply power to the flight controller by plug USB, wait until the red LED on the FC is off, immediately turn off the power, and then repeat again the above steps. When the FC is powered on for the third time, the red LED light will start to double-flash, which means that the Receiver enters the binding mode 2. Please make sure your ExpressLRS tx module firmware is v3.x.x. And go to ExpressLRS.lua from "TOOLS" menu of your radio transmitter. Then hit [Bind] to binding with the onboard ExpressLRS receiver. The red LED should blinking slowly first then turn to solid, that means binding was successfully. If the red led keep tri-flash after binding ,please change Model Match tab value from "off" to "on" or from "on" to "off" Receiver LED status meanings: Red LED solid means bind successful or RC link established; Red LED double-flash means get into bind mode; Red LED flash slowly means no RC signal input from TX module; Red LED continuous flash fast means ExpressLRS wifi enabled; Red LED tri-flash means model mismatch need to change model match from "off" to "on" . UART description: ELRS receiver was connected to UART2 default out of factory. Usually UART1 or UART6 Could be used for MSP OSD with HD VTX. UART6 could be used for GPS or other serial equipment. IRX6 is an inverted serial RX6 for SBUS input. IRX6 and TX6/RX6 couldn´t be used at the same time. NOTES: If upgrade firmware to betaflight 4.4.x , need to add custom Defines "GYRO_SPI_ICM42688P ACC_SPI_ICM42688P†from build configuration of betaflight configurator otherwise gyro will not working . If you want to enable Barometer , please connect to betaflight configurator and go to CLI command ,then type the following command: resource I2C_SCL 2 B10 resource I2C_SDA 2 B11 set baro_bustype = I2C set baro_i2c_device = 2 save Package Included: 1x CruxF405HD ELRS AIO Flight Controller 1x Antenna 1x Connector Cable 4x Anti-vibration Balls