iNav for the HGLRC Specter F722 Lite

A custom iNav target (HGLRCF722LITE) and ready-to-flash firmware for the HGLRC Specter F722 Lite flight controller — a board that stock iNav does not support.

Built & confirmed working 2026-08-03 on iNav 9.0.1.

Why this exists

The Specter F722 Lite (board_name HGLRCF722MINI, manufacturer HGLR) has an ICM42688P gyro, DPS310 baro, MAX7456 OSD, and 16 MB flash. The only HGLRC F722 target in stock iNav (HGLRCF722) compiles for MPU6000/BMI270 — not the ICM42688. The result: iNav boots and enumerates over USB but hangs before MSP, so the Configurator reports "MSP connection opened … no configuration received within 10 seconds." (Betaflight runs fine, which proves the hardware is good — it's purely a missing target.)

The fix is this target, HGLRCF722LITE, derived from MAMBAF722_2022A (a same-layout Mamba clone) with the ICM42688 driver enabled and every pin corrected to this board's real map, taken from a Betaflight 4.5.1 factory resource / diff all dump.

What's here

inav_9.0.1_HGLRCF722LITE.hex   flash this
target/HGLRCF722LITE/          the iNav target source (drop into src/main/target/)
  target.h  target.c  config.c  CMakeLists.txt
factory-dumps/                 ground-truth pin map, from Betaflight 4.5.1 on this board
  HGLRC_SpecterF722Lite_ResourceMap.txt
  HGLRC_SpecterF722Lite_Status.txt
  HGLRC_SpecterF722Lite_diffAll.txt

Flash it (no toolchain needed)

1. Open iNav Configurator 9.0.
2. Firmware Flasher → Load firmware [Local] → pick inav_9.0.1_HGLRCF722LITE.hex.
3. Tick Full chip erase.
4. Enter DFU: hold the BOOT button and replug USB.
5. Flash, then Connect.

Rebuild from source

The target is a standard iNav target — copy it into an iNav source tree and build:

git clone https://github.com/iNavFlight/inav.git
cd inav && git checkout 9.0.1
cp -r /path/to/target/HGLRCF722LITE src/main/target/
mkdir -p build && cd build
cmake ..                                    # first time; auto-fetches the ARM toolchain
cmake --build . --target HGLRCF722LITE -j"$(nproc)"
# -> build/inav_9.0.1_HGLRCF722LITE.hex

Build deps: cmake, ninja, ruby, gcc/make (the ARM cross-toolchain is fetched by cmake).

Pin map — deltas vs the Mamba baseline

Everything below comes from the factory dumps in factory-dumps/.

Peripheral	This board	Mamba baseline
Gyro	ICM42688P, SPI1 / CS PA4 / EXTI PC4	(only in Mamba_2022B)
Beeper	PC13	PB2
OSD MAX7456 CS	PB2	PB12
Flash M25P16	SPI2 / PB12 (SPI3 removed — was the boot-hang cause; PA15 is PINIO2)	SPI3
ADC VBAT / CURR / RSSI	PC2 / PC1 / PC0	PC1 / PC3
PINIO 1 / 2	PC3 / PA15	PC0 / PC2

Unchanged (already matched): all 6 UARTs, I2C1 (PB8/PB9), SPI1/SPI2, motor/timer map, LED strip PB3.

Runtime config (set in the Configurator, not compiled in)

• Internal ELRS RX → UART2, protocol CRSF (power the RX via the board's hardware jumper).
• GPS → UART4. TX↔RX crossover, VCC→5V, GND→GND.
• VTX SmartAudio → UART1 TX.
• Pitot / compass / rangefinder → I2C1 (PB8/PB9).

Caveats

• Gyro alignment is CW0_DEG, verified against Betaflight's orientation on the test board. If yours reads rotated, fix it at runtime with set align_board_*.
• VBAT_SCALE_DEFAULT is iNav's default (1100); calibrate against a known voltage if the battery reading is off.

Upstreaming

This target has been submitted upstream: iNavFlight/inav#11763. Under iNav's hardware policy, official inclusion (so the board appears in the stock Configurator target list) requires a sample board sent to a core developer. Until/unless that happens, flash from this repo with Load firmware [Local] as above.

License

GPLv3 — the target source is derived from iNav, which is GPLv3, so this repository is too. See LICENSE. Firmware © the iNav project and contributors; this target's pin-map work is contributed under the same license.