Problem with Hydra and GPS Module (.NET Gadgeteer Compatible)

Hi to all,
we develop on Hydra board with GPS module and we used a plublic gps driver (downloaded from

We write some codes and the module works, but the gps position is always “$GPRMC,V,N*53”.
We move gps module outside the house with clear sky but nothing.
We try to using the car to move the modulo around the house but nothing.

Is there something wrong?
We are alone with this problem?

Thanks to all for the answers.

You’ll need to be more specific to get any meaningful answers… What GPS? What driver on the gadgeteer site? Reading serial data is fairly trivial. It sounds like you need to some kind of initialization to configure the GPS on startup? The configuration specifics are usually manufacturer dependent.

Sorry for my poor information.
The module is SIM9000 (NEO-6 G6 HW-09005) bought at

We used a driver that we downloaded at

We init the module with this line:

_gps.InvalidPositionReceived += <EventName>;
_gps.PositionReceived+=  <EventName>; 

in the driver, on constructor, the code are the follow

Socket socket = Socket.GetSocket(socketNumber, true, this, null);

            powerControl = new GTI.DigitalOutput(socket, Socket.Pin.Three, true, this);
            gpsExtInt = new GTI.DigitalOutput(socket, Socket.Pin.Six, true, this);

            serial = new GTI.Serial(socket, 9600, GTI.Serial.SerialParity.None, GTI.Serial.SerialStopBits.One, 8, GTI.Serial.HardwareFlowControl.NotRequired, this);
            serial.AutoReadLineEnabled = true;
            serial.LineReceivedEventDelimiter = "\r\n";
            serial.LineReceived += new GTI.Serial.LineReceivedEventHandler(serial_LineReceived);

form the serial buffer we received other strings, but now I dont have. In this evening I will post more details.
We attach the module on port number 7.

So which event receives the ‘empty’ NMEA string? If you’re getting something back from the provided driver, then the place to look is the GPS itself. Your best bet is to contact the manufacturer of the GPS and/or get a user manual or datasheet for it. You can use this to verify that Seeed’s driver is doing what it should to initialize the GPS.

In general, the drivers Seed has provided to date are buggy, so while it sucks that this module is not ‘plug and play’, it is not surprising. I see you have responded to other posts about this hardware. I did not find any that indicated anybody here has actually has the GPS working.

@ devhammer has one, but I’m not sure if he has it working yet (based on another thread). Also, maybe GHI can test this module and provide some super simple demo code. Guys?

Hi, I would add more information.
This is the last logs:
GPS : $GPGGA,0,00,99.99,48
GPS : $GPGSA,A,1,99.99,99.99,99.99
GPS : $GPGSV,1,1,0079

For test I change socket number from 7 to 4, but nothing


to me this says the GPS isn’t locking on. The problem is more likely electrical interference or not giving the unit a long time (maybe 30 mins!) for first cold lock. How long did you sit it in the open sky for? What aerial wiring and placement relative to main electronics do you use?

GPS is not finding satellites. GPS so not work indoor.

Place it closer to a window or outside. It take a minute or more to lock to satellites.

Thanks for answers…

I place module outside of my house to more than one hour where the sky is clean, but nothing. No satellite finding.

I use the standard seeed’s antenna that has includes on package

Stupid question, you took teh whole system outside and left GPS powered fro over 5 minutes but still didn’t work?

yes I powered module for more than 5 minutes. Yesterday I leave the module outside for more than 1 hours, but no satellite find.

I try to find the documentation to undestand if the driver or something else is wrong, but I find only NEO6 schema documentation, but not a integration schema to check a connection and pin…

Then the antenna or the module maybe damaged?

I don’t think, but all is possibile

The module send me a strings and leds lighton( for the truth always red).
The antenna seems ok but I don’t now. How can I test it?

I tested the module with another antenna but result is the same.

Any ideas?

Thanks to all

Not sure myself

Is there an another module compatible with Hydra that works like a seeed’s module?
Do you know it?

I think I’ll change it…

@ John - if you mean is there another GPS module, I don’t think so.

Personally, I went with this one, . I use the breakout I made (see MakeBread to wire it to any gadgeteer mainboard. All I have to worry about is opening a COM port to talk to it, which is trivial. I can also use it with ANY microcontroller that talks serial. The antenna is embedded and it even has a spot for a battery to keep an RTC going. For $40, it’s a very fast and sensitive GPS.

Have you contacted Seeed directly about your issue? I would suggest asking for a refund or replacement if you cannot resolve the problem through usual support channels.

thanks ransomhall for answer.

I write on seeed’s forum ( but their not answer me yet.

i try to contact directly seeed’s support for refound

for our project we need to put a gps module inside a metal box. do you work? is there another module with external antenna?

thanks a lot for information

mine would not work well in a metal box. there are plenty of choices with external antennas