ppm_decode.h

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/**
 * @file ppm_decode.h
 *
 * PPM input decoder.
 */

#pragma once

#include <drivers/drv_hrt.h>

/**
 * Maximum number of channels that we will decode.
 */
#define PPM_MAX_CHANNELS    12

/* PPM input nominal min/max values */
#define PPM_MIN 1000
#define PPM_MAX 2000
#define PPM_MID ((PPM_MIN + PPM_MAX) / 2)

__BEGIN_DECLS

/*
 * PPM decoder state
 */
__EXPORT extern uint16_t    ppm_buffer[PPM_MAX_CHANNELS];   /**< decoded PPM channel values */
__EXPORT extern uint16_t    ppm_frame_length;               /**< length of the decoded PPM frame (includes gap) */
__EXPORT extern unsigned    ppm_decoded_channels;   /**< count of decoded channels */
__EXPORT extern hrt_abstime ppm_last_valid_decode;  /**< timestamp of the last valid decode */

__END_DECLS