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Permalink Reply by Greg Fletcher on March 19, 2010 at 10:13pm

The GPS comes from a special valid code from the GPS. The other analog sensors have nothing to do with the blue LED.
I don"t know what protocall your emulator uses, but the correct one must be selected in the "whatever.h" file(header file).
There are thee choices, EM406, NMEA, UBLOX. Try NMEA. Look for this line in the easystar_25 tab and set it.

#define GPS_PROTOCOL 2 // 0 = NMEA, 1=SIRF, 2=uBlox, 3 = IMU, 5 = Simulated GPS mode (Debug)

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Permalink Reply by RedQueen on March 19, 2010 at 10:52pm

Yes, the emulator is the GPS Emulator v1.2.6 included with the configtool software package. The correct data is going down the FTDI cable as verified by my terminal program, it is UBlox data formatted correctly. Currently my header file is set to Ublox (option 2) and identical to your code snip.

Must you use NMEA as the protocol when supplying GPS data over the FTDI?

My concern was that the code was hanging up looking for the sensors that are not attached. I guess this is not a possibility?

UPDATE: NMEA (GPRMC + GPGGA) at 38400 baud with a 4Hz refresh did not cause the GPS light to stop blinking.

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ModeratorPermalink Reply by Chris Anderson on March 19, 2010 at 11:13pm

We don't use standard uBlox format. We use binary format, with special settings as described here. If you're just going to use a GPS emulator, you should set it to NMEA mode and set the ArduPilot config file to protocol 0 (NMEA) and make sure you it's running at 38400 baud.

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Permalink Reply by RedQueen on March 20, 2010 at 9:12am

Like I mentioned above, I tried NMEA GPRMC + GPGGA sentences being supplied by the GPS emulator from the Configtool via FTDI at 38400 without success.

Has anyone used the GPS Emulator located here to achieve a lock?

http://diydrones.com/profiles/blogs/gps-emulator-now-outputs-ublox

I was under the impression that the new emulator was providing the Ublox data in the correct format. Is this not the case? The data stream looks to match the binary format the Ublox code in the Ardu is looking for?

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ModeratorPermalink Reply by Chris Anderson on March 20, 2010 at 10:54am

Mike, when you were using NMEA emulation, had you set the config file to NMEA?

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Permalink Reply by RedQueen on March 20, 2010 at 11:32am

Yup, sure was.. here is the snipp

#define GPS_PROTOCOL 0 // 0 = NMEA, 1=SIRF, 2=uBlox, 3 = IMU, 5 = Simulated GPS mode (Debug)

Here are my steps:

1) I set NMEA as the Protocol in code, and loaded to Ardupilot.
2) Started GPS emulator in NMEA mode supplying GPRMC and GGA on the FTDI serial port.
3) Attached the bind plug
4) Started radio and powered up Ardupilot
5) Blue light illuminated and flashed
but never goes out or steady on.

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Permalink Reply by RedQueen on March 26, 2010 at 12:59pm

Problem worked around. Split out the FTDI cable and pushed Tx to the 5v GPS IN pin. For lack of a better solution that will have to do. Instant GPS lock.

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