EM406A Messages

GPS/GNSS Development Boards
1

Hi,

I have an EM406A connected to a FEZ Domino board.

I can acquire and decode the GPRMC message.

Looking at the data sheet I see that other NMEA messages should be sent (like the GPVTG).

The problem is I can’t identify the GPVTG header.

I did not connect the module to a PC since I don’t have an RS232 transceiver on hand.

I would like to know if all messages written in the data sheet are outputted be default?

The data sheet is far from generous on the detail side of things… :lol:

Thanks,

S.B.D

2

I can confirm that my EM406 module does not, by default, output the GPVTG message.

Actually, I never noticed this until you pointed it out. By default I only see the following messages…

$GPGGA

$GPGSA

$GPGSV

$GPRMC

I’m not sure how you turn on the other messages.

3

Thanks!

I will contact the manufacturer and

post the reply…if they reply.

S.B.D

4

The PDF linked to from SparkFun (EM-406A_User_Manual.PDF) doesn’t render properly on my computer. I’m not sure if the SparkFun PDF if corrupt or if its some problem on my end. However, the manual directly from the GlobalSat page shows up fine…

http://www.usglobalsat.com/download/46/em406a_ug.pdf

There is text on Page 11 that describes sending a $PSRF103 message to the unit to turn on/off specific messages. I’m guessing this is what you want. (NMEA Input Command - Bullet ‘D’ - Page 11).

Please let me know if you get this to work.

5

Thanks PastaSauce!

Sparkfun’s link requires to download Chinese fonts, but even after the download them I couldn’t see the whole datasheet.

I will go over the datasheet you sent and try sending the $PSRF103 message.

Will let you know the outcome later on this week… I must give some attention to circuits that make money

not spend it :lol: .

6

Hi all

here is a list of some of the commands you can send to em406 to enable/disable messages:

// GGA-Global Positioning System Fixed Data, message 103,00
#define GGA_ON   "$PSRF103,00,00,01,01*25\r\n"
#define GGA_OFF  "$PSRF103,00,00,00,01*24\r\n"

// GLL-Geographic Position-Latitude/Longitude, message 103,01
#define GLL_ON   "$PSRF103,01,00,01,01*24\r\n"
#define GLL_OFF  "$PSRF103,01,00,00,01*25\r\n"

// GSA-GNSS DOP and Active Satellites, message 103,02
#define GSA_ON   "$PSRF103,02,00,01,01*27\r\n"
#define GSA_OFF  "$PSRF103,02,00,00,01*26\r\n"

// GSV-GNSS Satellites in View, message 103,03
#define GSV_ON   "$PSRF103,03,00,01,01*26\r\n"
#define GSV_OFF  "$PSRF103,03,00,00,01*27\r\n"

// RMC-Recommended Minimum Specific GNSS Data, message 103,04
#define RMC_ON   "$PSRF103,04,00,01,01*21\r\n"
#define RMC_OFF  "$PSRF103,04,00,00,01*20\r\n"

// VTG-Course Over Ground and Ground Speed, message 103,05
#define VTG_ON   "$PSRF103,05,00,01,01*20\r\n"
#define VTG_OFF  "$PSRF103,05,00,00,01*21\r\n"

// Wide Area Augmentation System, message 151
#define WAAS_ON    "$PSRF151,01*0F\r\n"
#define WAAS_OFF   "$PSRF151,00*0E\r\n"

Shamelessly borrowed from another forum :wink:

By default (or if left without power for sometime), it will only send GGA and RMC messages.

Mike