output_limit.h

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/**
 * @file output_limit.h
 *
 * Library for output limiting (PWM for example)
 *
 * @author Julian Oes <julian@px4.io>
 */

#pragma once

#include <stdint.h>
#include <stdbool.h>

__BEGIN_DECLS

/*
 * time for the ESCs to initialize
 * (this is not actually needed if the signal is sent right after boot)
 */
#define INIT_TIME_US 50000
/*
 * time to slowly ramp up the ESCs
 */
#define RAMP_TIME_US 500000

enum output_limit_state {
    OUTPUT_LIMIT_STATE_OFF = 0,
    OUTPUT_LIMIT_STATE_INIT,
    OUTPUT_LIMIT_STATE_RAMP,
    OUTPUT_LIMIT_STATE_ON
};

typedef struct {
    enum output_limit_state state;
    uint64_t time_armed;
    bool ramp_up; ///< if true, motors will ramp up from disarmed to min_output after arming
} output_limit_t;

__EXPORT void output_limit_init(output_limit_t *limit);

__EXPORT void output_limit_calc(const bool armed, const bool pre_armed, const unsigned num_channels,
                const uint16_t reverse_mask, const uint16_t *disarmed_output,
                const uint16_t *min_output, const uint16_t *max_output,
                const float *output, uint16_t *effective_output, output_limit_t *limit);

__END_DECLS