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Tips and questions relating to the GPS modules from SFE
By mo

I find the NMEA 'RT' command in any permutation I try puts the unit permanently to sleep and only a power reset will end. Serial port activity will not wake.

E.G., $PTNLSRT,S,3,111,30 should sleep for 30 seconds, and wake?

Does anyone have wisdom for me?

Thanks, mo.
By mo
Well, some people should not be allowed near keyboards, I guess that's me....

For those who may come along and need to know, properly it should have looked like this:


*Checksum not required.
*The second term can be set to '0' as not necessary to load to FLASH if power is not removed.
*And Wake Mode is the DECIMAL EQUIVALENT of what the manual calls for.

Now, if I can just sort out the syntax for the equivalent TSIP command that would be great.

By mo
the TSIP issues.

So the next guy doesn't have to go through this, there are errors in the manual also for the TSIP 'Standby' Command Packet 0xC0.

BYTE<0> manual calls for char 'F' to Standby. No. It is actually char 'S', H'53'.

BYTE<2> is a mess in the manual. decimal int's should be entered.
WAKE on PORT 1 is b'001' d'1'
WAKE on PORT 2 is b'010' d'2'
WAKE on TIMEOUT is b'100' d'4'

BYTE<3> is a 32 bit UINT
TIME is entered as a straight unsigned integer, unlike what the manual discussion says [IEEE754].

The manual also demands 'DLE' byte stuffing. This doesn't work.

Example for a 30 sec Standby is simply:

<10 C0 53 00 04 00 00 00 1E 10 03> and no checksum necessary.

Thanks Trimble.
By mo
Guess i'd better qualify..

This all with firmware V1.05, Build #4, 5/23/06

Mileage may vary, LSMFT, etc.

Enjoyed talking to myself. Thanks.
By forthguru
You weren't talking to yourself, many of us were listening, and perhaps the mental support we gave helped you pull it off - who knows!
Anyway, well done.
By mo
Thanks Forth.

The Copernicus is a really nice little device, I think.

I am finding that the specs on the unit are modest also. For instance, the book says the 1PPS is +/-50ns. I am finding that closer to 20ns. Nice.