MAVLink 学习笔记(c_library_v1-master)

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深入源码，学习v1版本的MAVLink架构，记录学习细节，巩固学习要点

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/* 文件组织结构，如下 */



/* 文件组织结构，见上 */

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typedef struct __mavlink_system
{
    uint8_t sysid;
    uint8_t compid;
} mavlink_system_t;


/**
* Used by the mavlink_send_xxx convenience functions
*/

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typedef struct __mavlink_message
{
    uint16_t checksum;
    uint8_t magic;
    uint8_t len;
    uint8_t seq;
    uint8_t sysid;
    uint8_t compid;
    uint8_t msgid;
    uint64_t payload64[(A + B + 7) / 8];
} mavlink_message_t;

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typedef struct __mavlink_extended_message
{
    mavlink_message_t base_msg;
    int32_t extended_payload_len;
    uint8_t extended_payload[C];
} mavlink_extended_message_t;

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typedef enum
{
    MAVLINK_TYPE_CHAR = 0,
    MAVLINK_TYPE_UINT8_T = 1,
    MAVLINK_TYPE_INT8_T = 2,
    ...
    MAVLINK_TYPE_FLOAT = 9,
    MAVLINK_TYPE_DOUBLE = 10
} mavlink_message_type_t;

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/**
* Applications can set "MAVLINK_COMM_NUM_BUFFERS" to the maximum number of buffers they will use.
* If more are used, then the result will be a stack overrun.
*/

#ifndef MAVLINK_COMM_NUM_BUFFERS
#if (defined linux) | (defined __linux) | (defined __MACH__) | (defined _WIN32)
#define MAVLINK_COMM_NUM_BUFFERS 16
#else
#define MAVLINK_COMM_NUM_BUFFERS 4
#endif
#endif

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mavlink_types.h中的所有数据结构

mavlink_system_t
struct类型，包含两个成员sysid、compid

mavlink_message_t
struct类型，包含8个成员checksum、magic、len、seq、sysid、compid、msgid、payload64[]

mavlink_extended_message_t
struct类型，包含3个成员mavlink_message_t base_msg、extended_payload_len、extended_payload[]

mavlink_message_type_t
enum类型

mavlink_field_info_t
struct类型，包含6个成员，两个字符串，mavlink_message_type_t type、三个定点数

mavlink_message_info_t
struct类型，包含3个成员，一个字符串，一个定点数，一个mavlink_field_info_t数组

mavlink_channel_t
enum类型

mavlink_parse_state_t
enum类型，用作通讯parser过程中的状态机

mavlink_framing_t
enum类型，包含3种，分别是"未完成"、"好了"、"校验异常"

mavlink_status_t
struct类型，包含9个成员，完后再仔细看和深入理解

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mavlink_helpers.h


/**
* @brief Reset the status of a channel.
*/


void mavlink_reset_channel_status(uint8_t chan)
{
    mavlink_status_t * status = mavlink_get_channel_status(chan);
    ststus->parse_state = MAVLINK_PARSE_STATE_IDLE;
}