EM406 Sirf binary Vs NMEA

EM406 Sirf binary Vs NMEA#18323

By rod_vdb - Mon Sep 04, 2006 3:55 am

- Mon Sep 04, 2006 3:55 am #18323

Has anyone else noticed that the data from the module is different in these two modes?

In NMEA the longtidue and lat are about 20miles off. when I switch to Sirf binary the long and lat are correct.

Anyone else experience this?

Cheers
Rod

#18328

By dmnamibia - Mon Sep 04, 2006 7:18 am

- Mon Sep 04, 2006 7:18 am #18328

Rod you must compare the dates correctly:
D.dddddd
D M.MMMM
D M S.ss
The reason for the difference is that you are comparing the data wrongly.
Sirf is most properly represented by D.dddddd which is not the case with NMEA.

#18333

By dmnamibia - Mon Sep 04, 2006 9:26 am

- Mon Sep 04, 2006 9:26 am #18333

Sorry Rob
The NMEA is represented as D M s
Latitute
Degree 2 characters
Minutes 2 Characters
and a variable number for decimal fractions of Minutes
Longitude
Degree 3 characters
Minutes 2 Characters
and a variable number for decimal fractions of Minutes
You will find that if you compute this to one number then it will look the same as the binary
(datum was a referece to WGS84 which is what the GPS follow by default)

#18342

By rod_vdb - Mon Sep 04, 2006 11:11 am

- Mon Sep 04, 2006 11:11 am #18342

Thank you, you are absolutly correct. It was because the numbers were so close to each other that I assumed that they should be the same! Silly me.

Thanks again

Rod

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