1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
/*
* mtk.h
*
* Created on: Mar 6, 2012
* Author: thomasgubler
*/
#ifndef MTK_H_
#define MTK_H_
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdbool.h>
#include <unistd.h>
#include <pthread.h>
//Definition for mtk custom mode
#define MEDIATEK_REFRESH_RATE_4HZ "$PMTK220,250*29\r\n" //refresh rate - 4Hz - 250 milliseconds
#define MEDIATEK_REFRESH_RATE_5HZ "$PMTK220,200*2C\r\n"
#define MEDIATEK_REFRESH_RATE_10HZ "$PMTK220,100*2F\r\n" //refresh rate - 10Hz - 100 milliseconds
#define MEDIATEK_FACTORY_RESET "$PMTK104*37\r\n" //clear current settings
#define MEDIATEK_CUSTOM_BINARY_MODE "$PGCMD,16,0,0,0,0,0*6A\r\n"
#define MEDIATEK_FULL_COLD_RESTART "$PMTK104*37\r\n"
//#define NMEA_GGA_ENABLE "$PMTK314,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0*27\r\n" //Set GGA messages
//definitions for watchdog
#define MTK_WATCHDOG_CRITICAL_TIME_MICROSECONDS 2000000
#define MTK_WATCHDOG_WAIT_TIME_MICROSECONDS 800000
// ************
// the structure of the binary packet
typedef struct {
uint8_t payload; ///< Number of payload bytes
int32_t latitude; ///< Latitude in degrees * 10^7
int32_t longitude; ///< Longitude in degrees * 10^7
uint32_t msl_altitude; ///< MSL altitude in meters * 10^2
uint32_t ground_speed; ///< FIXME SPEC UNCLEAR
int32_t heading;
uint8_t satellites;
uint8_t fix_type;
uint32_t date;
uint32_t utc_time;
uint16_t hdop;
uint8_t ck_a;
uint8_t ck_b;
} __attribute__((__packed__)) type_gps_bin_mtk_packet;
typedef type_gps_bin_mtk_packet gps_bin_mtk_packet_t;
enum MTK_DECODE_STATES {
MTK_DECODE_UNINIT = 0,
MTK_DECODE_GOT_CK_A = 1,
MTK_DECODE_GOT_CK_B = 2
};
typedef struct {
union {
uint16_t ck;
struct {
uint8_t ck_a;
uint8_t ck_b;
};
};
uint8_t decode_state;
// bool new_data;
// uint8_t fix;
bool print_errors;
int16_t rx_count;
uint64_t last_message_timestamp;
} __attribute__((__packed__)) type_gps_bin_mtk_state;
typedef type_gps_bin_mtk_state gps_bin_mtk_state_t;
extern pthread_mutex_t *mtk_mutex;
extern gps_bin_mtk_state_t *mtk_state;
void mtk_decode_init(void);
void mtk_checksum(uint8_t b, uint8_t *ck_a, uint8_t *ck_b);
int mtk_parse(uint8_t b, char *gps_rx_buffer);
int read_gps_mtk(int *fd, char *gps_rx_buffer, int buffer_size);
int configure_gps_mtk(int *fd);
void *mtk_loop(void *args);
void *mtk_watchdog_loop(void *args);
#endif /* MTK_H_ */
|
