The F4 1S 5A AIO Brushless Flight Controller is back in stock with new and upgraded features. The new board integrates Serial ExpressLRS 2.4G receiver. Compared with the original built-in SPI ELRS 2.4G receiver, it could flash the newest ELRS official firmware like V3.0 easily. Also, we updated the FC with high-quality BMI270 gyro, BB51 ESC hardware with Bluejay ESC firmware, and 8MB Betaflight Blackbox flash.
Please click here to F4 1S 5A AIO (SPI ELRS 2.4G) if you need information about it.
Tons of ExpressLRS items are available now!
Two version choices for the FC board. Weighing only 2.96 grams, the Light version comes with NO motor connectors soldered. Therefore, pilots could directly solder the motor cables to the FC board, getting an ultimate lightweight drone for fast speed FPV racing.
| Light Version | Classical Version | |
| Weight | 2.96g | 3.64g |
| Board Thickness | 0.8mm | 0.8mm |
| Motor Connectors | Not Solder | Soldered |
Below is the diagram for Serial ELRS 2.4G RX. The diagram for the Classical and Light versions is the same.
Below is the diagram for SPI Frsky RX. The diagram for the Classical and Light versions is the same.
Serial ELRS 2.4G RX uses the Crossfire serial protocol (CRSF protocol) to communicate between the receiver and the flight controller board. So the Serial ELRS 2.4G RX is available to support upgrading to ELRS V3.0 with no need to flash Betaflight flight controller firmware. Enter binding status by power on/off three times.
The Serial ELRS 2.4G RX can be updated via Wi-Fi or Betaflight serial passthrough. Here is the way to update the Serial ELRS 2.4G RX firmware through passthrough.
How to flash firmware via Wi-Fi here.
Come with the built-in SPI Frsky Receiver (CC2500 chip), F4 1S 5A AIO FC can be compatible with Futaba S-FHSS, Frsky D8, and D16 protocol. The default protocol is configured to Frsky D16 FCC out of the factory. Pilots could set up the protocol according to your own need in Betaflight Configurator.
| Configuration | Protocol |
| FRSKY_D | Frsky D8 |
| FRSKY_X | Frsky D16 FCC (ACCST 1.X version) |
| FRSKY_X_LBT | Frsky D16 LBT (ACCST 1.X version) |
| SFHSS | Futaba S-FHSS |
How to Bind with Betaflight FC with SPI Frsky Receiver.
F4 1S 5A AIO Brushless Flight Controller comes with the default firmware betaflight_4.3.0_BETAFPVF411 (ELRS) or betaflight_4.2.11_BETAFPVF411RX (Frsky). The default firmware for Serial ExpressLRS 2.4G RX version supports ELRS V2.4 RX.
Pay attention, For the Serial ExpressLRS 2.4G version, ONLY the Betaflight firmware 4.3.0 and up start to support this BMI270 gyro. For the SPI Frsky version, DO NOT flash the other firmware, otherwise, the RX will be lost in control at a very close range. We have already built our own firmware betaflight_4.2.11_BETAFPVF411RX for SPI Frsky RX version to support BMI270 gyro. Please check the below link to download the firmware.
Note: The RX RSSI values drop when the flight controller is installed on the quadcopter with HD digital VTX (Walksnail or HDZero). For example, the theoretical failsafe RSSI values for 250Hz packet rate are -108dBm. Actually, the RX will be possibly lost in control when the RX RSSI values reach about -92dBm.
F4 1S 5A flight controller with BB51 ESC hardware could flash the Bluejay ESC firmware now, which is based on BLHeli_S revision 16.7. With Bluejay ESC firmware, it supports bidirectional D-shot and RPM filtering in Betaflight, offers 24KHz, 48KHz, and 96KHz fixed PWM frequency for options, and custom start-up melodies. By using Bluejay ESC firmware on Meteor65 and Meteor65 Pro whoop drones with 0802SE 19500KV motors, the flight time is increasing effectively. The default firmware for F4 1S 5A FC will be changed to Bluejay ESC firmware.
For pilots who want to flash Bluejay ESC firmware for F4 1S 5A FC, please use the BLHeliSuite16714902A_Beta or ESC-Configurator and download Bluejay ESC firmware A_X_5_.HEX from the below links. (Both Light and Classical versions share the same firmware)
Note: Only SPI ELRS 2.4G version supports motor direction set through Betaflight Configurator and SPI Frsky version does not support it. BLHeli Configurator and Bluejay Configurator are invalid for the BB51 ESC (both versions).
Both Serial ExpressLRS 2.4G RX and SPI Frsky RX version support external HD digital VTX or Analog VTX. Please note that the SPI Frsky RX version reserves an SBUS port and a UART port, which is available for the SBUS protocol receiver or other external receivers. You can refer to the below picture. The diagram is the same for Classical and Light version.
