bool GPS_NMEA_newFrame(char c) {
uint8_t frameOK = 0;
static uint8_t param = 0, offset = 0, parity = 0;
static char string[15];
static uint8_t checksum_param, frame = 0;
if (c == '$') {
param = 0; offset = 0; parity = 0;
} else if (c == ',' || c == '*') {
string[offset] = 0;
if (param == 0) { //frame identification
frame = 0;
if (string[0] == 'G' && string[1] == 'N' && string[2] == 'G' && string[3] == 'G' && string[4] == 'A') frame = FRAME_GGA;
if (string[0] == 'G' && string[1] == 'N' && string[2] == 'R' && string[3] == 'M' && string[4] == 'C') frame = FRAME_RMC;
} else if (frame == FRAME_GGA) {
if (param == 2) {
GPS_Info.GPS_coord[LAT] = GPS_coord_to_degrees(string);
}
else if (param == 3 && string[0] == 'S')
GPS_Info.GPS_coord[LAT] = -GPS_Info.GPS_coord[LAT];
else if (param == 4)
{GPS_Info.GPS_coord[LON] = GPS_coord_to_degrees(string);}
else if (param == 5 && string[0] == 'W')
GPS_Info.GPS_coord[LON] = -GPS_Info.GPS_coord[LON];
else if (param == 6) {
fgps.GPS_FIX = (string[0] > '0');
GPS_Info.GPS_Fixed = fgps.GPS_FIX;
}
else if (param == 7) {
GPS_Info.GPS_numSat = grab_fields(string,0);
}
else if (param == 9) {
GPS_Info.GPS_altitude = grab_fields(string,0);
} // altitude in meters added by Mis
} else if (frame == FRAME_RMC) {
if (param == 7) {
GPS_Info.GPS_speed = ((uint32_t)grab_fields(string,1)*5144L)/1000L;} //gps speed in cm/s will be used for navigation
else if (param == 8) {
GPS_Info.GPS_ground_course = grab_fields(string,1);
} //ground course deg*10
}
param++; offset = 0;
if (c == '*') checksum_param=1;
else parity ^= c;
} else if (c == '\r' || c == '\n') {
if (checksum_param) { //parity checksum
uint8_t checksum = hex_c(string[0]);
checksum <<= 4;
checksum += hex_c(string[1]);
if (checksum == parity) frameOK = 1;
}
checksum_param=0;
} else {
if (offset < 15) string[offset++] = c;
if (!checksum_param) parity ^= c;
}
if (frame) GPS_Info.GPS_Present = 1;
return frameOK && (frame==FRAME_GGA);
}
static bool GPS_NMEA_newFrame(char c)
{
uint8_t frameOK = 0;
static uint8_t param = 0, offset = 0, parity = 0;
static char string[15];
static uint8_t checksum_param, frame = 0;
if (c == '$')
{
param = 0;
offset = 0;
parity = 0;
}
else if (c == ',' || c == '*')
{
string[offset] = 0;
if (param == 0)
{ //frame identification
frame = 0;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'G'
&& string[3] == 'G' && string[4] == 'A')
frame = FRAME_GGA;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'R'
&& string[3] == 'M' && string[4] == 'C')
frame = FRAME_RMC;
}
else if (frame == FRAME_GGA)
{
if (param == 2)
{
gps.coord[LAT] = GPS_coord_to_degrees(string);
}
else if (param == 3 && string[0] == 'S')
gps.coord[LAT] = -gps.coord[LAT];
else if (param == 4)
{
gps.coord[LON] = GPS_coord_to_degrees(string);
}
else if (param == 5 && string[0] == 'W')
gps.coord[LON] = -gps.coord[LON];
else if (param == 6)
{
if (string[0] > '0')
flagSet(FLAG_GPS_FIX);
else
flagClear(FLAG_GPS_FIX);
}
else if (param == 7)
{
gps.numSat = grab_fields(string, 0);
}
else if (param == 9)
{
gps.altitude = grab_fields(string, 0); // altitude in meters added by Mis
}
}
else if (frame == FRAME_RMC)
{
if (param == 7)
{
gps.speed = (grab_fields(string, 1) * 5144L) / 1000L; // speed in cm/s added by Mis
}
else if (param == 8)
{
gps.ground_course = grab_fields(string, 1); // ground course deg * 10
}
}
param++;
offset = 0;
if (c == '*')
checksum_param = 1;
else
parity ^= c;
}
else if (c == '\r' || c == '\n')
{
if (checksum_param)
{ // parity checksum
uint8_t checksum = hex_c(string[0]);
checksum <<= 4;
checksum += hex_c(string[1]);
if (checksum == parity)
frameOK = 1;
}
checksum_param = 0;
}
else
{
if (offset < 15)
string[offset++] = c;
if (!checksum_param)
parity ^= c;
}
return frameOK && (frame == FRAME_GGA);
}
static int gpsNewFrameNMEA(char c)
{
uint8_t frameOK = 0;
static uint8_t param = 0, offset = 0, parity = 0;
static char string[15];
static uint8_t checksum_param, frame = 0;
if (c == '$') {
param = 0;
offset = 0;
parity = 0;
} else if (c == ',' || c == '*') {
string[offset] = 0;
if (param == 0) { // frame identification
frame = 0;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'G' && string[3] == 'G' && string[4] == 'A')
frame = FRAME_GGA;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'R' && string[3] == 'M' && string[4] == 'C')
frame = FRAME_RMC;
} else if (frame == FRAME_GGA) {
if (param == 2) {
gpsData.lat = GPS_coord_to_degrees(string);
} else if (param == 3 && string[0] == 'S')
gpsData.lat = -gpsData.lat;
else if (param == 4) {
gpsData.lon = GPS_coord_to_degrees(string);
} else if (param == 5 && string[0] == 'W')
gpsData.lon = -gpsData.lon;
else if (param == 6) {
gpsData.fix = string[0] > '0';
} else if (param == 7) {
gpsData.numSatellites = grab_fields(string, 0);
} else if (param == 9) {
gpsData.height = stringToFloat(string);
}
} else if (frame == FRAME_RMC) {
if (param == 7) {
gpsData.speed = stringToFloat(string) * 51.44444f; // speed in cm/s
}
}
param++;
offset = 0;
if (c == '*')
checksum_param = 1;
else
parity ^= c;
} else if (c == '\r' || c == '\n') {
if (checksum_param) { // parity checksum
uint8_t checksum = hex_c(string[0]);
checksum <<= 4;
checksum += hex_c(string[1]);
if (checksum == parity)
frameOK = 1;
}
checksum_param = 0;
} else {
if (offset < 15)
string[offset++] = c;
if (!checksum_param)
parity ^= c;
}
if (frame)
gpsData.present = 1;
return frameOK && (frame == FRAME_GGA);
}
static bool GPS_newFrame(char c)
{
uint8_t frameOK = 0;
static uint8_t param = 0, offset = 0, parity = 0;
static char string[15];
static uint8_t checksum_param, frame = 0;
if (c == '$') {
param = 0;
offset = 0;
parity = 0;
} else if (c == ',' || c == '*') {
string[offset] = 0;
if (param == 0) { //frame identification
frame = 0;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'G' && string[3] == 'G' && string[4] == 'A')
frame = FRAME_GGA;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'R' && string[3] == 'M' && string[4] == 'C')
frame = FRAME_RMC;
} else if (frame == FRAME_GGA) {
if (param == 2) {
GPS_latitude = GPS_coord_to_degrees(string);
} else if (param == 3 && string[0] == 'S')
GPS_latitude = -GPS_latitude;
else if (param == 4) {
GPS_longitude = GPS_coord_to_degrees(string);
} else if (param == 5 && string[0] == 'W')
GPS_longitude = -GPS_longitude;
else if (param == 6) {
GPS_fix = string[0] > '0';
} else if (param == 7) {
GPS_numSat = grab_fields(string, 0);
} else if (param == 9) {
GPS_altitude = grab_fields(string, 0);
} // altitude in meters added by Mis
} else if (frame == FRAME_RMC) {
if (param == 7) {
GPS_speed = ((uint32_t) grab_fields(string, 1) * 514444L) / 100000L;
} // speed in cm/s added by Mis
if (param == 8) {
GPS_heading = grab_fields(string, 0);
} // heading
}
param++;
offset = 0;
if (c == '*')
checksum_param = 1;
else
parity ^= c;
} else if (c == '\r' || c == '\n') {
if (checksum_param) { // parity checksum
uint8_t checksum = hex_c(string[0]);
checksum <<= 4;
checksum += hex_c(string[1]);
if (checksum == parity)
frameOK = 1;
}
checksum_param = 0;
} else {
if (offset < 15)
string[offset++] = c;
if (!checksum_param)
parity ^= c;
}
return frameOK && (frame == FRAME_GGA);
}
/***********************
函数功能：GPS接收数据处理,解码字符串
输入参数：串口接收到一字节数据
***********************/
static bool GPS_NewFrame(char c)
{
u8 frameOK = 0; //数据更新是否完成
static u8 param = 0; //在一帧中的哪一段，0段为引导码
static u8 offset = 0; //字符串数组用到
static u8 parity = 0; //校验码记录
static char string[15]; //临时保存每一段需要解析的字符串
static u8 checksum_param;//校验
static u8 frame = 0; //这一桢是哪种格式的，这里用到GPGGA和GPRMC格式
if(c == '$') //$符号为一帧数据的起始符号
{
param = 0; //一帧开始，初始化这些变量
offset = 0;
parity = 0;
}
else if(c == ',' || c == '*')//逗号为一段字符结尾，星号表示结束，后面的是校验码等
{
string[offset] = 0; //让临时字符串最后一位为0结束,这个0是ascii的0呢
if(param == 0) //第0段储存着哪种数据格式
{
frame = 0;
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'G' && string[3] == 'G' && string[4] == 'A')
frame = FRAME_GGA; //GPGGA数据格式
if (string[0] == 'G' && string[1] == 'P' && string[2] == 'R' && string[3] == 'M' && string[4] == 'C')
frame = FRAME_RMC; //GPRMC数据格式
}
else if(frame == FRAME_GGA) //进入GPGGA数据格式处理
{
if(param == 2) //纬度
{
GPS_coord[LAT] = GPS_Coord_to_Degrees(string);//将纬度转换为ddmm.mmmmm，度分格式
}
else if (param == 3 && string[0] == 'S') //判断是否是南纬
GPS_coord[LAT] = -GPS_coord[LAT]; //南纬是正,北纬是负
else if (param == 4) //经度
{
GPS_coord[LON] = GPS_Coord_to_Degrees(string);//将经度转换为ddmm.mmmmm，度分格式
}
else if (param == 5 && string[0] == 'W') //判断是否是西经
GPS_coord[LON] = -GPS_coord[LON]; //西经用负表示
else if (param == 6) //定位质量，0为无效定位，1为有效
{
f.GPS_FIX = string[0] > '0'; //string[0] > '0'成立则说明是有效，标记GPS_FIX
}
else if (param == 7) //使用的卫星数目
{
GPS_numSat = Grab_Fields(string, 0);//将字符转换为数字,卫星数目
}
else if (param == 9) //海拔高度
{
GPS_altitude = Grab_Fields(string, 1); //单位是分米
}
}
else if(frame == FRAME_RMC) //在这桢获取速度
{
if (param == 7) //速度，准确说是速率呵呵，
{
GPS_speed = ((uint32_t) Grab_Fields(string, 1) * 5144L) / 1000L; // 换算单位为CM/S的速度
}
}
param++; //字符段加1
offset = 0; //临时保存字符串清0
if (c == '*') //判断是否到校验码了
checksum_param = 1;//标记到检验码了
else
parity ^= c; //奇偶校验，$和*之间的ascii位或的值，要等于校验码
}
else if(c == '\r' || c == '\n')
{
if(checksum_param) //进入校验
{
u8 checksum = hex_c(string[0]);
checksum <<= 4;
checksum += hex_c(string[1]);
if (checksum == parity) //相等，则数据正确无误
frameOK = 1;
}
checksum_param = 0;
}
else
{
if (offset < 15)
string[offset++] = c;//保存字符
if (!checksum_param)
parity ^= c;
}
//if(frame)
// GPS_Present = 1;
return frameOK && (frame == FRAME_GGA); //数据完全更新成功一次，返回1
}
