DRONE FC
Flight controllers, firmware, stack sizes
PROCESSOR COMPARISON
| CHIP | CLOCK | MAX LOOP | FEATURES | NOTES |
|---|---|---|---|---|
| STM32 F4 | 168MHz | 8kHz | OSD, blackbox (SPI) | Budget standard. Sufficient for most builds. No hardware inversion on UART. |
| STM32 F7 | 216MHz | 8kHz | OSD, blackbox, hardware inversion | Better peripheral support. Full UART flexibility. Good mid-range choice. |
| STM32 H7 | 480MHz | 8kHz+ | Full features + faster MCU | Top tier. Handles heavy filtering and logging with headroom. Future-proof. |
| AT32 | 288MHz | 8kHz | F7-level features | F7 clone from Artery Tech. Budget alternative to F7. Betaflight supported. |
FC FEATURES
OSD (On-Screen Display)
Overlays data onto video feed — battery voltage, mAh consumed, RSSI, GPS coordinates, speed, altitude. Essential for FPV. Betaflight OSD is configurable per element.
BLACKBOX LOGGING
Records gyro, motor outputs, RC inputs to flash memory or SD card. Used for PID tuning analysis. Flash is faster; SD holds more data. Betaflight Blackbox Explorer for review.
BAROMETER
Altitude hold in altitude modes. Optional for freestyle/racing, essential for INAV or autonomous flight. Accuracy varies — GPS altitude is usually more reliable.
GYRO / IMU
MPU6000 is the gold standard — SPI connection, low noise. ICM42688-P is newer and better. Avoid I2C gyros (too slow). Gyro quality directly affects tune quality.
AIO vs STACK
AIO (All-In-One)
FC and ESC on single board. Compact and light — ideal for 2–4" builds. Less flexible if one part fails — must replace whole board. Current limited (typically 25–35A per motor).
SEPARATE STACK
FC board + separate ESC board stacked via M3 posts. More modular — replace FC or ESC independently. Higher current ratings. Better airflow. Standard for 5"+ builds.
FIRMWARE
| FIRMWARE | BEST FOR | FEATURES | NOTES |
|---|---|---|---|
| Betaflight | Racing / freestyle | PID tuning, RPM filter, OSD, Blackbox | Most popular. Large community. Optimised for manual flying. |
| INAV | Long-range / wings | GPS navigation, return-to-home, waypoints | Navigation focused. Works on planes and boats too. |
| ArduPilot | Autonomous / commercial | Full autopilot, mission planning, multi-rotor, planes | Most capable. Complex setup. Used in professional builds. |
| Emuflight | Lightweight / whoop | Betaflight fork, optimised for small frames | Smooth filtering for 1–3" builds. Less overhead than BF. |