Hi All
I have an application where I want to poll a neo-m8n (need data only when requested). I have tried a couple existing libs but the issue seems to be that I have to continually feed the data as opposed to just getting data when requested. The solution I came up with was a combination of reading the GPS using the code from
http://www.monocilindro.com/2016/03/28/reading-gps-data-using-arduino-and-a-u-blox-neo-6m-gps-receiver/ as the base and a tokenizer that I found at CS 221 . It works when I set it up to read the gps using a terminal command 'r'. The main code is as follows (parser and tokenizer seem to be ok):
#include <elapsedMillis.h>
//#include <cstring>
#include <Streaming.h>
#include <math.h>
#define mySerial_GPS Serial2
#define defaultTelemTime 1500
elapsedMillis telem_timer;
#define cout Serial
// Function prototype
char *myStrtok(char *parseStr, char *splitChars);
char tokChars[8]; // Array of characters used to split on
char *cptr; // Pointer to string returned by tokenizers
int count; // Counter for words in the string
bool first_loop_exec;
#define GPS_INFO_BUFFER_SIZE 256
char GPS_info_char;
char GPS_info_buffer[GPS_INFO_BUFFER_SIZE];
unsigned int received_char;
uint8_t i; // counter
bool message_started;
uint8_t GPS_mess_no = 0;
uint8_t array_idx = 0;
String gpsdata[25];
bool first_gsa = true;
struct utc {
int mils;
int seconds;
int minutes;
int hours;
} datetime;
String op_mode;
int fix, sats_in_use;
String fixtype;
float latlng_age, time_age;
float fix_age, pdop, hdop2, vdop, dop_age, hdop1;
float alt_age, altitude, vVel, sog, cog;
double longitude, latitude;
int val;
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(57600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
Serial.println("Connected");
mySerial_GPS.begin(57600);
//mySerial_GPS.println("Connected");
first_loop_exec=true;
i=0;
message_started=false;
telem_timer = 0;
strcpy(tokChars, ",");
}
void loop() { // run over and over
//if(telem_timer > defaultTelemTime) {
if(cout.available() > 0){
val = cout.read();
}
if( val == 'r'){
cout << "request data" << endl;
read_gps();
telem_timer = 0;
}
}
void read_gps(){
mySerial_GPS.println("$PUBX,00*33"); // data polling to the GPS
// MANAGES THE CHARACTERS RECEIVED BY GPS
while (mySerial_GPS.available()) {
GPS_info_char = mySerial_GPS.read();
if (GPS_info_char == '
If I change the loop to read the gps every 1 sec for example nothing gets to the parser, changed loop code:
void loop() { // run over and over
if(telem_timer > defaultTelemTime) {
//if(cout.available() > 0){
// val = cout.read();
//}
//if( val == 'r'){
//cout << "request data" << endl;
read_gps();
telem_timer = 0;
}
}
From some debugging it appears that the PUBX message never completes. Not sure what the issue is. If anyone has any suggestions please let me know since this one is driving me crazy.
Mike){ // start of message
message_started=true;
received_char=0;
} else if (GPS_info_char == '*'){ // end of message
//cout << GPS_mess_no << " ---> " << endl;
//for (i=0; i<received_char; i++){
// Serial.write(GPS_info_buffer[i]); // writes the message to the PC once it has been completely received
//}
//Serial.println();
// Make initial call to strtok() passing in the string to be parsed and
// the list of characters used to split tokens apart.
cptr = strtok(GPS_info_buffer, tokChars);
count = 1; // Initialize the word counter
// Create while() loop to print all the tokens in the string. Note that
// the punctuation has been eliminated leaving just the words from the string.
// As long as NULL is passed in as the first argument to strtok it will
// continue parsing the last "non-NULL" string passed to it. It returns
// NULL when the entire string has been parsed.
while(cptr != NULL)
{
gpsdata[count] = "";
for(int len = 0; len < strlen(cptr); len++){
gpsdata[count] = gpsdata[count]+cptr[len];}
//cout << "Token " << count << " -->" << gpsdata[count] << "<--\n";
cptr = strtok(NULL, tokChars); // Get next word
count++; // Increment counter
}
read_pubx();
val = 0;
message_started=false; // ready for the new message
} else if (message_started==true){ // the message is already started and I got a new character
if (received_char<=GPS_INFO_BUFFER_SIZE){ // to avoid buffer overflow
GPS_info_buffer[received_char]=GPS_info_char;
received_char++;
}else{ // resets everything (overflow happened)
message_started=false;
received_char=0;
}
}
}
while (Serial.available()) {
mySerial_GPS.write(Serial.read());
}
}
If I change the loop to read the gps every 1 sec for example nothing gets to the parser, changed loop code:
§DISCOURSE_HOISTED_CODE_1§
From some debugging it appears that the PUBX message never completes. Not sure what the issue is. If anyone has any suggestions please let me know since this one is driving me crazy.
Mike
)
It's not even documented as "deprecated".
