Has anyone had any luck using the EB-85A Chip?

GPS/GNSS Development Boards
1

Has anyone had any luck using the EB-85A Chip? I have been attempting to get it to work 9 ways to Sunday. No luck. I used the recommended temporary Eval board (EM406 SiRF III Evaluation Board - RS232) but no success.

Sparkfun got it to work when I RMAed it but I am not having any luck.

I get the following stuff…

0 0.00008549 MiniGPS_1.32.ex IRP_MJ_CREATE Serial0 SUCCESS Options: Open

1 0.00000559 MiniGPS_1.32.ex IOCTL_SERIAL_GET_BAUD_RATE Serial0 SUCCESS

2 0.00000391 MiniGPS_1.32.ex IOCTL_SERIAL_GET_LINE_CONTROL Serial0 SUCCESS

3 0.00000391 MiniGPS_1.32.ex IOCTL_SERIAL_GET_CHARS Serial0 SUCCESS

4 0.00000363 MiniGPS_1.32.ex IOCTL_SERIAL_GET_HANDFLOW Serial0 SUCCESS

5 0.00001648 MiniGPS_1.32.ex IOCTL_SERIAL_SET_BAUD_RATE Serial0 SUCCESS Rate: 38400

6 0.00000894 MiniGPS_1.32.ex IOCTL_SERIAL_SET_RTS Serial0 SUCCESS

7 0.00000922 MiniGPS_1.32.ex IOCTL_SERIAL_SET_DTR Serial0 SUCCESS

8 0.00000698 MiniGPS_1.32.ex IOCTL_SERIAL_SET_LINE_CONTROL Serial0 SUCCESS StopBits: 1 Parity: NONE WordLength: 8

9 0.00000447 MiniGPS_1.32.ex IOCTL_SERIAL_SET_CHAR Serial0 SUCCESS EOF:0 ERR:0 BRK:0 EVT:0 XON:0 XOFF:0

10 0.00000670 MiniGPS_1.32.ex IOCTL_SERIAL_SET_HANDFLOW Serial0 SUCCESS Shake:1 Replace:40 XonLimit:0 XoffLimit:0

11 0.00000363 MiniGPS_1.32.ex IOCTL_SERIAL_SET_QUEUE_SIZE Serial0 SUCCESS InSize: 4096 OutSize: 128

12 0.00000391 MiniGPS_1.32.ex IOCTL_SERIAL_SET_TIMEOUTS Serial0 SUCCESS RI:0 RM:0 RC:100 WM:0 WC:500

13 0.00000838 MiniGPS_1.32.ex IOCTL_SERIAL_PURGE Serial0 SUCCESS Purge: RXCLEAR

14 0.00007347 MiniGPS_1.32.ex IRP_MJ_WRITE Serial0 SUCCESS Length 14: $PMTK605*31…

15 0.10934043 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 29: $PMTK705,Mcore_1.51,0131*21…

16 0.03041839 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000642.805,8960.000000,N,00000.000000,E,0,0,137.000,M,13

17 0.00978393 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: ,1E…$GPGSV,1,1,0079…$GPRMC,000642.805,V,8960.000000,N,00000 18 0.10936250 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 39: $GPVTG,0.00,T,M,0.000,N,0.000,K,N*32…

19 0.04192125 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000643.004,8960.000000,N,00000.000000,E,0,0,137.000,M,13

20 0.10929937 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 91: 0.000000,N,00000.000000,E,0.000,0.00,060180,N*4B…$GPVTG,0.00,

21 0.06999996 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000643.204,8960.000000,N,00000.000000,E,0,0,137.000,M,13

22 0.10925383 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 91: 0.000000,N,00000.000000,E,0.000,0.00,060180,N*49…$GPVTG,0.00,

23 0.06681827 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000643.404,8960.000000,N,00000.000000,E,0,0,137.000,M,13

24 0.10940022 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 91: 0.000000,N,00000.000000,E,0.000,0.00,060180,N*4F…$GPVTG,0.00,

25 0.06367038 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000643.605,8960.000000,N,00000.000000,E,0,0,137.000,M,13

26 0.10934714 MiniGPS_1.32.ex IRP_MJ_READ Serial0 TIMEOUT Length 91: 0.000000,N,00000.000000,E,0.000,0.00,060180,N*4C…$GPVTG,0.00,

27 0.06156593 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: $GPGGA,000643.805,8960.000000,N,00000.000000,E,0,0,137.000,M,13

28 0.00964815 MiniGPS_1.32.ex IRP_MJ_READ Serial0 SUCCESS Length 100: ,1E…$GPGSV,1,1,0079…$GPRMC,000643.805,V,8960.000000,N,00000

2

You should be able to just hook it up to a PC running hyperterm (using a suitable level-shift interface (I just use a Max chip) and it will spit out all the default sentences without any worries.

The MiniGPS program is the most useful method of setting/changing defaults if you need to.

We have the EB85s in use on UAVs and they work just fine and dandy.

3

As you can see in the log, I am seeing empty GPS coordinates. Hyperterm sees it just fine and is getting the same thing. I used the Microsoft Serial Port Debugger http://www.microsoft.com/technet/sysint … rtmon.mspx

to spy on the communications between the chip and the ETEK software (Mini GPS & GPSTrace).

ETEK has been useless for support. I’m not sure if they are interested in the this product. Other manufacturers are more atune to supporting users.

4

Hi,

Have you tried leaving out outside for 12-15 minutes? Thats the time needed for it to acquire a new almanac if its lost of invalidated the onboard one.

I was one of the guys that tested it at SFE - we powered it up on a windowsill and it just started spitting out coords.

Cheers,

–David Carne

5

Yep, they are slower to acquire satellites and build an almanac than some other chipsets so you have to be patient initially.

On the dump you provide, the GPS quality indicator field is 0, as is the number of SVs – which indicates that it hasn’t found any satellites (yet).

I’m actually quite impressed with the sensitivity of these units, they work inside an iron hangar that has only a couple of plastic panels in the roof.

6

I get the same data strings as you if I have no signal.

Take it outside so you get some good line of site signal. Then run the PMTK COLD START command.

7

add 3.3v battery supply, or you will wait a few mins evey time to build almanac from scratch, and only close to a large Pb-free window.