pwm_limit.h

/****************************************************************************
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 *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
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 * modification, are permitted provided that the following conditions
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#ifndef PWM_LIMIT_H_
#define PWM_LIMIT_H_

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

__BEGIN_DECLS

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

enum pwm_limit_state {
    PWM_LIMIT_STATE_OFF = 0,
    PWM_LIMIT_STATE_INIT,
    PWM_LIMIT_STATE_RAMP,
    PWM_LIMIT_STATE_ON
};

typedef struct {
    enum pwm_limit_state state;
    uint64_t time_armed;
} pwm_limit_t;

__EXPORT void pwm_limit_init(pwm_limit_t *limit);

__EXPORT void pwm_limit_calc(const bool armed, const bool pre_armed, const unsigned num_channels,
                 const uint16_t reverse_mask, const uint16_t *disarmed_pwm,
                 const uint16_t *min_pwm, const uint16_t *max_pwm,
                 const float *output, uint16_t *effective_pwm, pwm_limit_t *limit);

__END_DECLS

#endif /* PWM_LIMIT_H_ */