The ITEAD studio GPS I bought has a Ublox NEO 6M module on it.
There is a Ublox utility for working with the GPS on their web site, but I suspect you cannot communicate with it via the arduino uno usb port, and my attempts to alter the data rate to other than 38,400bps were ineffective.
There is a real lack of documentation for this unit other than the data sheet and a detailed manual for that module (which indicated that 9600 bps is the default data rate). It would be nice if there were the equal of the “AT” command set to modify the behavior of the module.
The sentences produced all seem to be truncated (missing the checksum). I understand that fairly recently (last couple of years?)that NMEA sentence was modified to add another character of information before the checksum. Other sentences produced on startup seem to have checksums attached, only the $GPRMC that appears after a few minutes lacks the checkum.

Perhaps I can find a way to communicate with the GPS module directly and alter the data rate, but for the moment, I can find no way to chage to 4800 or 9600 bps.
Thanks, Peter
Would there be any Arduino buffers that should be increased in size?

Mikal:

If I were to detach the GPS shield and then load a sketch into the Arduino that interfaced the GPS to the Arduino on pins 0 and 1, I think I would be using a faster hardware interface?? I could then remount the GPS shield, reboot and use a monitoring program, but without the need for the SoftSerial library. Do you think this would help with the speed problem?

Peter

silly me – I will still need two ports to talk to two devices. I guess I could use the softserial port to communicate between the Arduino and the PC, and the hardware port to communicate from the GPS to the Arduino. I am assuming the hardware port is more capable of higher speeds than softserial.

Mikal:

To follow up on the above:

The ITEAD GPS Shield 1.1 is equipped with a UBlox Neo 6m gps module on an Arduino shield.
As you recall, I asked for help since it appeared to be generating incomplete sentences (and therefor no fix). The hardwired default RATE WAS 38,400 BPS.
I found that by using some $PUBX commands to the ublox GPS in a sketch (found on the net), I could change the rate to 4800. I should mention I found at least one opinion that 19,200bps is as fast as SoftwareSerial can go on an Arduino Uno.
At any rate, the GPS now works perfectly, even getting good reception thru a closed glass window. (11 sats) So the main thrust of this email is to let you know the Itead GPS works, but not faster than 4800 bps via SoftwareSerial.
However, one problem remains. After changing the port’s bps rate, if I remove power the new setting vanishes and I then have to “re-install the rate change.
Question: Do you know a $PUBX command to store the configuration data in the eblox GPS module in non-volatile memory? I can’t find any references to a complete function list of $PUBX commands.

Pete

First to Pete, thank you for those of us pulling our hair out wishing to use iTead shield and TinyGPS++. The $PUB commands work and I would never have found without your post. For the record, starting with SoftwareSerial at 38400, I added the following lines to my setup.
…
ss.print(“$PUBX,41,1,0007,0003,4800,0*13\r\n”); // Change iTead baudrate
ss.begin(4800); // reset SoftwareSerial baudrate
ss.flush();
delay(50);

I am a newbie and delay(50) may not be required but seemed to help.
The following reference I found indicates there is no nonvolatile memory and that battery backup would be required.
http://ukhas.org.uk/guides:ublox6#software_serial_configuration_example

Mikal, great library, I want to add my thanks to all the myriad others I have seen directed to you while searching for a solution to this problem.

Further update on the Itead GPS shield:
I found that I could use the AltSoftSerial.h library with better results. I can run the GPS at 38,400 and get excellent results. However, the AltSoftSerial routines are “hardwired” to pins 8 and 9 of the Uno. I made a simple 2 wire jumper that took the signal from the Itead pin selection block Rx row and Tx row ( any pin in either row), and routed them to pins 8 and 9. Of course, remove the jumpers from the pin select jumper block.
For some reason, my Itead GPS never seems to listen, so I can’t easily switch speeds, and it can’t remember modified parameters on power cycling, but since it is hardwired to default to 38400 BPS, this is fine.
I don’t know if it is defective, or if it my ignorance that’s the problem, but I have worked around it.

Here’s the “test” code from AltSoftSerial.h modified for bps rates:

#include

// AltSoftSerial always uses these pins:
//
// Board Transmit Receive PWM Unusable
// —– ——– ——- ————
// Teensy 2.0 9 10 (none)
// Teensy++ 2.0 25 4 26, 27
// Arduino Uno 9 8 10
// Arduino Mega 46 48 44, 45
// Wiring-S 5 6 4
// Sanguino 13 14 12

AltSoftSerial altSerial;

void setup() {
Serial.begin(38400);
Serial.println(“AltSoftSerial Test Begin”);
altSerial.begin(38400);
altSerial.println(“Hello World”);
}

void loop() {
char c;

if (Serial.available()) {
c = Serial.read();
altSerial.print(c);
}
if (altSerial.available()) {
c = altSerial.read();
Serial.print(c);
}
}

Hope this helps.

Just to add a small comment to this thread on communicating with high Baud rate gps’ (I am using a 5Hz, 57,600 baud rate 66 channel LS20031 GPS). There is certainly an issue with serialSoft. Other forums have suggested increasing the buffer in the serialSoft library to get around this.

Personally I take the easy route and up load my sketch and then connect the GPS to pin 0 and 1 afterwards.

Hi Mikal,

Thanks very much for creating and maintaining this library.

I’m using the Adafruit Ultimate GPS library with battery backup, which essentially functions as a RTC and outputs the correct time even though no fix is established. I’ve been doing some testing, and it seems like TinyGPS is filtering out these sentences as there is no valid fix.

I’m attempting to modify the library to parse the date/time before evaluating the sentence checksum (in the TinyGPS::term_complete() function). Do you think this will create any further issues with the rest of the library?

Thanks

Mikal,

Thank you for your superbly functioning GPS utility. I was initially using my own routines for NMEA parsing but there were some puzzling issues with truncated sentences. Your TinyGPS example with the reported statistics was a welcome 2nd opinion which helped me find reliable settings for the baud rate and NMEA sentence repeat rate.

I could use an even tinier Tiny GPS so I would like to see if I can trim out any functionality I won’t be using. I am trying to log not only GPS data to an SD card, but also the data from the many sensors in the AdaFruit 10 degree of freedom inertial measurement unit.

The SD card library is not small, and the 10-DOF IMU libraries aren’t small either. I can log GPS data to the SD; the remaining RAM at that point is 383 bytes. When I include the IMU’s data my free RAM shrinks down to 355 bytes and the sketch will simply not run. Any trimming I can do should get me closer to a workable sketch.

The GPS fields I wish to log are Date, Time, Lat, Lon, Altitude, Course, and Speed in mph. The 10-DOF will be contributing 3 axes each for Accelerometer, Magnetometer, and Gyroscope.

Can you offer any advice for trimming down TinyGPS? I’ve been looking through the SD and also the AdaFruit sensor libraries but haven’t found any low-hanging fruit there yet.

I am running the iTead Studios GPS shield with an UNO for the purpose of controlling 4 external relays that operate every 15 seconds to provide timing interlock for several paging transmitters that share the same channel.
The problem that I am experiencing is that the time shown by the GPS is about 9 seconds behind actual time.
I am using TinyGPS++ but have also seen the same error with TinyGPS.
Have you or anyone else noticed this time error?
Occasionally after reloading the sketch the time will be correct for a few minutes then return to the 9 second late error.
Thanks, Tim

no matter what i do i cant get past the “Tinygps does not name a type error
I can see the libart in the arduino libary folders but I cant get it to work.

thanks john

Hello.,
Guys i really need some help here. I’m interfacing a gps receiver with my arduino mega. I have a simple gps receiver with nmea output. I tried reading sequence.I used to get proper loc. But now am able to receive only GPVTG. Can anybody please help me on this.

Hi!

The TinyGPS++ custom fields capability looks very interesting for an application we have in mind, but I need to check a few details first!

Basically, we’re looking to replace some of the unused/irrelevant (I hope) data in the NMEA strings with telemetry data, recalculate the checksum, and then forward that to the ground station.

Basically, does TinyGPS++ use the GPGGA fields such as: Height of geoid above WGS84 ellipsoid, DGPS reference station id, and other oddballs?

Lastly, if you simply want lat/long and altitude, can TinyGPS+ extract those from a GPGGA-only sting? (uBlox receivers can limit the strings transmitted, allowing you to optimize wireless bandwidth)

Thanks!

I seem to have a problem between tinygps and ledcontrol.h . ledcontrol stoppes working as soon as I start an instance of tinygps. Has anyone else encountered this problem with the 2 libraries running in the same sketch?

Hello Mikal,

I’m use your library, but not have any data from Iteastudio GPS shield.

My code is here https://github.com/Ladeia/TCC/blob/master/gps/gps.ino

and I use the ports RX 4 and TX 3.

I need help…

Tim- my class is using the same board as you (itead gps v1.1) and an UNO rev3 on Arduino IDE 1.05, but cannot get any of the examples from tinyGPS++ to work. We get nothing but ****** stars.How did you get yours up and running?

However, we do get valid gprmc data, and the sentence count is 0 when the simple test from tinyGPS (no plus) is run, and the baud rate of the gps softserial is set to 38400. From Arduino 1.00 up the baud limitation has supposedly been lifted on software serial.
I’ve been searching the net and forums until my eyes bled for an answer to get the gps unit working, any help will be welcome from someone who has the same itead gps v1.1.

it would be nice to put a download for this somewhere where someone can find it, is there a prize for someone who locates it?

@Mikal,

I am getting the following $gprmc stream using your TinyGps simple test and uncommenting the serial read(c).(tinygps++ examples do not have an option to view the raw serial, and I do not have enough experience to add it in yet)

$GPRMC,001707.00,A,4230.22586,N,08258.44727,W,0.262,,220414,,,D1 CHARS=642 SENTENCES=0 CSUM ERR=0
$GPRMC,001708.00,A,4230.22595,N,08258.44728,W,0.226,,220414,,,DG. CHARS=707 SENTENCES=0 CSUM ERR=0
$GPRMC,001709.00,A,4230.22622,N,08258.44724,W,0.215,,220414,,,D1 CHARS=771 SENTENCES=0 CSUM ERR=0
$GPRMC,001710.00,A,4230.22641,N,08258.44724,W,0.105,,220414,,,D0W CHARS=836 SENTENCES=0 CSUM ERR=0
$GPRMC,001711.00,A,4230.22660,N,08258.44723,W,0.137,,220414,,,D, CHARS=900 SENTENCES=0 CSUM ERR=0
$GPRMC,001712.00,A,4230.22673,N,08258.44726,W,0.040,,220414,,,D0 CHARS=964 SENTENCES=0 CSUM ERR=0
$GPRMC,001713.00,A,4230.22681,N,08258.44724,W,0.218,,220414,,,D, CHARS=1028 SENTENCES=0 CSUM ERR=0

As you can see, I have a valid fix noted by the A, latitude and long data, many characters and no sentences.
@Antonio Ladeia- if I get this working I’ll let you know, because it looks like we are in the same situation.

Hi Mikal,

I am in the process of building a box*(arduino Uno), using the Audafruit GPS Shield. I have had some success so far. However I am to the point of implementing a Time Constraint/ Time limit using the date and time from the GPS module.
If you can offer any incite into how to run this data…I would appreciate it.

Thanks,
@AaronHAll

why I am getting *************** at the serial monitor of the arduino Uno.

Hello,

I used the exact code. However, if I were to use “if(gps.encode(gpsSerial.read()))”, it won’t execute whatever codes below. If I were to change it to “if(gpsSerial.read())”, the longitude and latitude are both 999999999999999.

Please assist.

Hello Mikal!

Awesome work with TinyGPS! It has sped my development along!

I have a uBlox 5 GPS and an Arduino Pro Mega. The GPS data arrives on one of the UARTs and TinyGPS parses the data. I’ve been able to reduce the number of GPS sentences coming from the GPS to improve bandwidth and, presumably, reduce discarded sentences. I also set the GPS baud to 19200. Lastly, I transmit the GPS data using a RFM DNT900.

The main loop calls a function to process incoming GPS sentences using TinyGPS. My understanding is when encode() returns true, valid GPS data is available. When GPS data is valid, I transmit the data. The set up for the transmission requires a bit of time but I have not had an issue transmitting valid GPS data once per second.

I am seeing some odd behavior and wanted to ask about it. Occasionally, I see the same GPS data transmitted twice:

4137228,-8142981,25760,30,29900,170514,16013800
4137228,-8142981,25760,30,29900,170514,16013800
4137227,-8142980,25740,106,29612,170514,16014000

My theory is the loop executes fast enough that it calls encode() before more GPS data arrives. That is, I get valid GPS data, transmit it, call encode() and it returns true because the previous data is valid.

My goal is to have GPS data transmitted once per second. What data might I use from TinyGPS to help with that goal?

Thanks,
Joe

@Joe Follow Up

Hello Mikal!

I did some experiments today. I changed the program to transmit GPS data only when the current and previous GPS time are different. This check is made immediately after calling encode for the last character received from the GPS.

This successfully limits the transmission to once per second and only when the GPS time changes. I’m still curious about your thoughts on this.

Thanks,
Joe

Hello Mikal,
I’m using your librairy, but I want to use an Xbee in paralel with it.

The problem is: I don’t now how to assigne an another specific serial output to the TinyGPS.

Can you help me please?

Thanks

@Mikal

Yes, I’m using an arduino mega.
Now, the problem is that I’m sending NMEA sentences that was given in your example by an arduino UNO, to an arduino MEGA.
I have checked the MGA receive the sentences, but the problem is that it can’t extract the course from it.

Thanks for helping me

Can you please explain how and where does the TinyGPS library do all the required calculations to get the fix?

I’m trying to make a power budget for a TinyGPS.

And does anyone have experience what the time is from cold start to have a fixed position. I know that it can vary depending on factors like clouds, partly seen sky and so on.

I have an unusual behaviour when it comes to your library.

i have arduino duemilanove and em408
My code is this:

#include <Arduino.h>
#include <TinyGPS.h>

#define GPS_RX_PIN 2
#define GPS_TX_PIN 3

TinyGPS gps;
SoftwareSerial ss(GPS_RX_PIN, GPS_TX_PIN);

void setup()
{
  Serial.begin(9600);
  ss.begin(4800);
  }

void loop()
{
  while (ss.available())
  {
    char c = byte(ss.read());
    // Here i tried Serial.write(c); and i succesully saw the NMEA data in my serial monitor
    if (gps.encode(c))
    {
      long lat, lon;
     unsigned long fix_age;
    gps.get_position(&amp;lat, &amp;lon, &amp;fix_age);
    if (fix_age == TinyGPS::GPS_INVALID_AGE )
      Serial.println("No fix ever detected!");
    else if (fix_age &gt; 2000)
      Serial.println("Data is getting STALE!");
    else
      Serial.println("Latitude and longitude valid!");

      Serial.print("Lat: ");
      Serial.print(lat);
      Serial.print(" Lon: ");
      Serial.println(lon);

    }
    else Serial.println("Not encoded data!");
  }
}

My output is this:

No data!
No data!
No data!
No data!

No data!
No data!
No data!
No data!
No data!
No data!
No data!
No data!
No data!
Latitude and longitude valid!
Lat: 32758239
Lon: 15637489
No data!
No data!
No data!
No data!
No data!
No data!
No data!

And then i continue getting No data! forever…

So… 1. Why does gps.encode() only manage to return true only 1 time? I have gotten the raw data from the gps (the commented code on my code snippet) and it’s ok. Why it returns true only one time?

2. Why the longitude/latidude data is like this? As far as i know, this isnt valid, correct?

Hi again Mikal.

Please disregard my previous email for help.
I have your excellent library working beautifully. Many thanks for that.

My problem was simple. I downloaded the library and renamed it to TinyGPS.
Unfortunately the files within the folder were still named TinyGPS13 (the current version).
The compiler reported the Library as installed, when in fact it was not! I had extracted the files…. but of course they still had the old name within the new folder. Stupid me!
It now works 100%.

Kind regards,
Allan (in sunny Scotland) :-)

Hi Mikal. Great library. Do you know of any code to transmit TinyGPSPlus data over 2 nrf24l01′s? 1 TX 1RX.

G’day
Fantastic Library! Love It.

Have you considered option to allow use of TinyGPS::distance_between with longs instead of floats?

Mikal & Users

So many thanks – this really is a most fantastic piece of work.

Kevin Walton & Terry Baume have forked previous versions to include some great additions for ublox recievers.
Enabling the use of request / response gps updates instead of being hit with NMEA sentences constantly.
I understand that your library has been designed to be non device specific, and further that the TinyGPS plus library has support for custom sentences, so I see why you have not rolled these additions into your source.

I have updated Kevin and Terrys work to include your V13 updates and its available here: https://github.com/HarperBen/TinyGPS

Again Mikal – thanks – through developing and releasing this library you saved me several days swearing at a gps module – Champion.

i want to send a complete sentence gpgga for example to an seial port…is there a command for tiny GPS for a complete sentence ???

Mikal , i want to ask u that how to show the calculating of the latitude and longitude in the program? and then how to show the value like an example -7.281495 that the value of the latitude, but on my program only show in serial.print in -7.28 like that…, can u explain to me please, thanks before…