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Tips and questions relating to the GPS modules from SFE
By corvette123
#71101
anyone tried the Venus yet??

looks pretty sweet!!! :)

great job sparkfun!!
By jeanseb
#71392
corvette123 wrote:anyone tried the Venus yet??

looks pretty sweet!!! :)

great job sparkfun!!
I've ordered one and I'm waiting for it to arrive.

Could anybody confirm that the only way to talk to the unit is via the serial IO, and that the SPI interface should only be used for interfacing with an external memory?

Thanks
By gm
#71411
I've been playing with the module over the weekend and so far, I'm impressed with its sensitivity. I've gotten a lock inside my house within 38 seconds from a cold start and I've been able to track up to 11 satellites. The antenna I am using is an active Sarantel.

I'm pretty sure the only way to communicate with it is through the async port and the SPI port is strictly for data logging to an eeprom chip.
By jsampson
#71533
gm wrote:The antenna I am using is an active Sarantel.
Where did you get the active Sarantel antenna? I didn't see those on Sparkfun.
By gm
#71585
I didn't get it from Sparkfun. We use them at work. We buy them from Jim Gary & Associates. I was also using it with a passive patch antenna today and it was working great! It has a bulit-in LNA that seems to be quite good.

I was measuring the current consumption and it was drawing about 70 milliamps when it was acquring but then it drops down to about 30 milliamps while it's tracking.

All in all, I'm pretty impressed with it. Next project is to design my own GPS board using this chip.
By corvette123
#71605
jim D gray is a P.I.M.P !!!

theyve got some mighty nice things in that store..


but dont call too early in the morning cuase they hit the sauce pretty damned good there hahahahahah :)

but thats texas i guess....
By corvette123
#71606
its a whole nother country.

thats where all my ex wives live too.
By Falcon X
#71726
Go ahead and say RTFM if you need to, but for quick evaluation purposes... all I would need is the FT232 (serial to usb) connected to the GND, TX, RX, VCC pins of the GPS-09133, correct? I'm assuming the SPI pins are for an optional SPI flash chip but what are VBAT, PPS, 1, 2, and 20 used for (i.e. why are they routed out)?

I'm hoping to make a cool sky map tracking the az, el, and SNR of all acquired satellites over time.
By jsampson
#71779
Falcon X wrote:Go ahead and say RTFM if you need to, but for quick evaluation purposes... all I would need is the FT232 (serial to usb) connected to the GND, TX, RX, VCC pins of the GPS-09133, correct?
This was an interesting question so I looked. Sparkfun says it can be used with their BOB-00718 USB converter board. But isn't the GPS 3.3V and not 5V which USB uses? Looking at the data sheet for the FT232RL is shows that it has a 3.3V regulator and somewhere is says you can draw 50ma for you own logic.

The GPS-09133 appears to draw "~28ma", which is the only number I saw. At first glance it looks like you could use either GPS-00177 or GPS-00464 antenna. They say 12ma. So 12+28=40ma which is below the 50ma so it looks like it should work.

So it looks to me like you could connect those two boards together for evaluation purposes.
Falcon X wrote:I'm assuming the SPI pins are for an optional SPI flash chip but what are VBAT, PPS, 1, 2, and 20 used for (i.e. why are they routed out)?
The SPI pins are for a flash part. The other pins are brought if you decide to use them. However, it looks to me like the VBAT pin should be labeled 3.3V instead of VBAT. The schematic shows VBAT tied directly to 3.3V. So it looks to me like you can't use the external battery to save the volatile data. (i.e., you will have to do a cold start every time you turn it on)
Falcon X wrote:I'm hoping to make a cool sky map tracking the az, el, and SNR of all acquired satellites over time.
By perds
#77972
About this chip.. I'm getting some null data

$GPRMC,181019.000,V,0000.0000,N,00000.0000,E,000.0,000.0,300709,,,N*7B
$GPVTG,000.0,T,,M,000.0,N,000.0,K,N*02
$GPGGA,181020.000,0000.0000,N,00000.0000,E,0,00,0.0,0.0,M,0.0,M,,0000*67
$GPGSA,A,1,,,,,,,,,,,,,0.0,0.0,0.0*30

Am I required to send commands to configure the chip, or is the chip supposed to start getting data as soon as it finds a satellite?

Am I just having bad reception issues?
By perds
#78088
Nevermind, solved :) just bad reception.
By dimkasta
#80142
Is there a way to put it on sleep mode?
I want to make my project really energy conscious, so I just need to get an initial reading and then put it to sleep.
I read through the datasheet and couldn t find anything relevant other than the vbat pin which is tied to V so no powering it up and down fast.

Any suggestions?
By corvette123
#80153
is there ANY distributors carrying the BGA version of this chip???

that LGA is sooo...... passe'...
By corvette123
#80154
errr oops its not the exact same chip...


but its close.


yes theres a BGA venus chip !!
By DC REdD
#80178
I'm hoping someone can help me out...

I got one of the Venus634FLPx GPS IC's. I knocked up a board with one of the SFE GPS Chip antennas and an FT232RL. Hooked it all up and plugged it in.
So far so good, I get the NMEA stream in the SKYTRAQ GPS Viewer software. However it doesn't appear to be able to find any satellites. I reset it a few times and supplied initial position and time (part of the reset feature in the software) and woohoo, I started to get somewhere. I eventually got a good lock seeing 6 or 7 satellites with a DOP down to 1.5. This was out in the conservatory, so I disconnect it from the power take it in too see if I can get a lock indoors, no luck. Take it back out, now nothing, nothing, nothing?!? Argghh

The other odd behaviour I see is that most of the binary messages are OK, i.e. requesting the software version etc. However if I try to download AGPS data to the GPS it times out. The only way to get anything out of the GPS again it to power cycle it or use the reset pin.

Any help would be appreciated.

Arran