GPSDO

[9a4qv]

DCD na RS232

Qv

[9a4qv]

Srecko,

Malo sam ti pogledao datasheet od modela kojeg imas.
Taj model je malo drukciji od standardnih koji se koriste za gpsdo.

Na njega bi se trebao spojiti koristeci software LabMon koji se vrti u DOS-u ali ima i WinLabMon koji se vrti na Windozama ali ja sam nasao samo verzije koje dejstvuju na win 95/98.

Uglavnom, po defaultu, tebi je GPS setiran da radi u Binary protokolu i da bi ga prebacio u NMEA treba ti taj sw. Najprije se zakacis u binary protocolu na njega, pa onda unutar menija promijenis protokol na NMEA.

Da budem iskren, nemas sta puno kopati po GPS-u, mislim da ti je jednostavnije napraviti klasiku od GPSDO i zaboraviti na RS-232 komunikaciju jer ti ona u biti i ne treba, sve sto ti treba imas prikazano na LCD, ovisno o verziji koju mislis koristiti.

Dakle bitno ti je da imas 10khz izlaz  drugo ces lako.
Nadam se da imas aktivnu antenu, bolje to radi ...

QV

[9A1X]

Ok Adame, skinuo sam WinLabMon i sve spojio. Nista ne trza.
Morat cu pogledati na osciloskopu da vidim dali GPS salje podatke.
Spajam na kompjuter cisto da vidim dali je GPS zalokan, inace napravio sam verziju sa PIC-om i LCD-om pa onda netreba kompjuter.
Sve mi se cini da cu morati vratiti GPS 

[9a4qv]

Srećko, jesi radio ovako nešto u zraku sa štipaljakama ili kulturno sa kablom i pravim konektorom.
Ako nije "IKEBANA" style onda neće raditi 

QV

[9A1Z]

QV to ništa ne valja!
Display i GPS antena nisu na istoj koordinati!

[9A1X]

Adame, ovo kod tebe je uredno za 5. Nisam uslikao kako je bilo kod mene, bez stipaljka, ali zato zica i lemljenja na sve strane. Malo sam stao sa home varijantom GPSDO-a, ali je zato nabavljena tvornicka verzija (Trimble Thunderbolt). Trenutno se rade drugi projekti, odnosno dovrsavaju. Uskoro na forumu!

[9a4qv]

Evo za one koji koriste stari Jupiter modul koji je toliko star da mu je 2015 bila daleka buducnost 
Problem krivog prikazivanja datuma (koji je nastao ovaj mjesec) moze se rijesiti ako to nekome prestavlja problem. Vrijeme je tocno i ono nema problema koa zulja datum evo kako to ispeglati i gps ce raditi i slijedecih 20 godina..

AH - Its happened.    You don't say which GPS module you are using, but I bet its a Rockwell Jupiter

Can I refer you to an email I received from Jim Miller   G3RUH relating to the GPS modules he uses in his GPSDO.  Text is copied below.   Its because those modules are so old, they're rolled over and only appear to use a modulo 2^10 week count

If you subtract 1024 weeks from today's date (28 Feb) you get 15 July 1995  . 

As for SOG readings, This has arisen before, but I can't remember what it was .    I may have updated the PIC firmware on my website.   http://www.g4jnt.com/GPLOCDIS.ZIP    There's a later version of the firmware in there, dated 2010 but I can't remember the differences

Andy   G4JNT

---------------------------------

From G3RUH :

I need to flag up a problem with the Jupiter GPS engine in respect of its
display of the date.  I pass this on to you as you may be using the date
information in beacon applications.

As of 2015 Feb 15 [Sun], upon power-on and then acquiring satellite lock, the
displayed date shows exactly 1024 weeks prior to the true date. (After nearly
20 years of otherwise perfect operation).

If the unit has not been powered off, then the (correct) Date is maintained.

This issue does not affect the Time, which remains always correct.

In all other respects; almanac, acquisition, lock, 1PPS, 10 kHz, data streams
NMEA or binary; everything is completely normal. DSP engines work in GPS week
number; the "date" is a presentation layer thing for humans.

If the Jupiter's date output is important to you, then you must initialise the
date yourself, as follows.

With the GPS receiver RS-232 stream in NMEA mode, send the command string:
$PRWIINIT,A,,,,,,,,,,,,000000,ddmmyy[CR][LF]
with the appropriate date.

Example; for 2015 Dec 31 you would send:

$PRWIINIT,A,,,,,,,,,,,,000000,311215[CR][LF]

Note: this is 36 ASCII bytes plus 2 terminating bytes CR LF, (hexadecimal
0x0D  0x0A), making a total of 38 bytes.  The CR+LF are essential, and must be
in that order.  There are 14 ","s in the string.  There is no tolerance for
error in this byte sequence.  For example, your dumb terminal software must
not add any characters to the end of the sequence.

A file,  init_date.txt  that contains this command can be found in

http://www.jrmiller.demon.co.uk/projects/ministd/jupcom.zip

Another option is to implement back-up of the RTC and SRAM, which is a 3V
to 5V signal applied to pin 3 of the 20 way connector.  The drain is about
50 µA. The voltage can usefully be from a NiCd/NiMH/Li rechargeable battery,
or even 3x AAA Duracell.

Once correctly initialised, the date should remain correct indefinitely.


Hope useful.

73 de James G3RUH

pozz
QV

[9A1X]

Upalite svoje GPS(DO) uredjaje, jer ce veceras stati vrijeme 1 sekundu, odnosno 1 minuta ce imati 61 sekundu (leap second). U 23:59:59 po UTC ili 01:59:59 po lokalnom vremenu.