ESPFlight Docs v1
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Safety & Failsafe

Use Firmware v1.0.0 safety semantics as observable bench-test rules, not only as background theory.

ESPFlight Docs · v1 • Validated v1 documentation path

# ARM-ready means motors off

ARM is explicit. Firmware accepts ARM only when throttle is at or below 1050 and the required link, failsafe, battery and IMU checks are healthy. A successful ARM enters an ARMED-ready state; at throttle ≤ 1050 all normal motor PWM remains zero.

VERIFY THIS ON THE BENCH

With propellers removed, ARM at minimum throttle and confirm telemetry reports ARMED while the motors remain off. If a motor spins in this state, stop and diagnose before flight.

# Throttle and DISARM behavior

Normal motor output begins only after real throttle rises above 1050. Returning throttle to ≤ 1050 stops normal motor PWM but does not automatically DISARM. Explicit DISARM at low throttle resets assist/PID state and writes zero PWM to all four motors.

# Low-battery safety note

The v1 firmware battery/failsafe value is a calibrated ESP supply-voltage proxy read through ESP.getVcc(); it is not a direct raw LiPo-pack voltage measurement. Firmware v1.0.0 uses a tested low-voltage trigger of 2.6 V on that regulated-supply proxy and latches battery lockout after the validated condition. Do not compare this number directly with a 1S LiPo pack voltage.

# Flight-time behavior

Flight time accumulates only while the Drone is ARMED and effective throttle is strictly above 1100. It pauses at 1100 or below and stops on DISARM.