I am trying to use this GPS chip for a long term application where i need very low power usage. I am wondering if anyone has used an external SD card so the chip can start from hot start each time? Or if there is another way to prevent cold start each lock. For reference I need a lock each 5 minutes and I am wondering how I can start from hot start each time.

Was this the point of the super capacitor which is no longer available, and what would be the power usage to replace that capacitor with a battery?

Thanks!

As far as I can read as the data sheet this device can report position even higher than 40 km if I stay bellow Mach 1 speed?

So it will work for a HIgh altitude balloon project?

I started implementing a python library for controlling the Venus6. https://github.com/rudolfbyker/venus6 Pull requests are welcome.

Hello,

I’m currently working on implementing this board into a high altitude balloon for studying the eclipse later this year, and after some testing and stuff I realized I really liked the capabilities of the board, but was annoyed at lotsa libraries size and complexity in use and reading when for the most part, I’m just logging the data to an SD card for analysis later.

So I decided I’d try making my own library for this board. Since the binary commands are relatively simple and can also be read using the configuration software and an arduino to watch the commands being sent, I thought I’d be able to implement a library that can change the settings using functions, which would mean the board could be configured more easily through code in your setup function rather than needing to permanently change settings through the configuration software. I didn’t like the idea of the permanent setting changes because in my experience some setting combinations like 20Hz at 9600 baud would totally mess up the data and make it unreadable, so making sure all saves are temporary prevents this headache that I experienced.

Anyway, it’s a work in progress that I’ll be updating more over the next few days to finish all the features I need and adding more examples and images for wiring since I could see how a newer person could get mixed up at a lot of points with this board. It would be such a shame for the learning curve to prevent a newbie from using such a cool board. Here it is. Check the page every couple days for updates. https://github.com/Darthpbal/Hermes_Gps_Library

This lib works trough a readLine, getLine, printLine kinda workflow. It has a filter so if you wanna record all the GPS data, you can set that to raw, and if you ONLY want GGA or RMC, you can turn on the filter and only get that. And if you don’t wanna record the whole line of GGA, but only the latitude, longitude and altitude, I’ve implemented the same field parser from the tutorial, so you can easily extract a particular field within the GGA sentence since it follows the NMEA standard. I don’t have the stuff for changing the GPS settings itself yet, but like I said. That’s coming soon. And I'll also probably add examples for logging to an sd card as well since I saw that asked somehwere.

http://www.gpsinformation.org/dale/nmea.htm#GGA

https://github.com/Darthpbal/Mercury_Gps_Library

Hope this helps someone.

hello. i received yesterday this module and also bought an active magnetic sma antenna. i get the GPRMC data successfully on arduino + digole i2c screen, and fast signal lock, but i have the following issues: 1. the lat-lon position is somewhat off by 30 kilometers. it is showing steady position, but wrong 2. the time is wrong (-3 hours), should i add 3 hours in general as i am in gmt+2? 3. the data seems to have a delay. the speed for example goes zero after 3-4 seconds after i stop with the car. the other data stabilize also after 4-5 seconds. 4. i read that the lat-long numbers can never go actually to 10-20hz update, you get 20hz data but the numbers change at 1hz, is that true? i am still new to this, i suppose i need to do some serial connection to pc and do some firmware configuration/settings? all i want is fast (10hz+) lat/long updates for a trackday app i am making.

The only data we needed from this board was found in the GGA string. I could not find a way to only return that string. found that using the TinyGPS++ library was the simplest method I could find to pull just that information I needed. Make sure to leave gps.altitude.isUpdated() set to altitude. If you change it to location.isUpdated or time.isUpdated it will throw off your timing because both location and time are updated multiple time in different parts of the NMEA string.

**Great GPS Module BUT ONE Problem***

The Venus GPS board has no carrier to make it easier to integrate. So, I modified an older USB Adapter for XBEE, the XBee Explorer USB WRL-08687. The inside hole pattern is just right for the Venus board. If you turn the module around so that the RF antenna connector is pointed the same way as the USB connector, and move it to the far end of the hole pattern, it works perfect. You get Ground, 3.3V, DOUT (Tx0) and DIN (Rx0) right where you want it. I used (2) 4-pin and (2) 3-pin socket connectors and separated them one hole to isolate RTS and DIO12. That way CTS, RTS and DTR are not connected from the USB chip to the Venus. It works great for USB connectivity.

I received 1 of these in the last "Ding and Dent Production Builds" order. But I did not have enough time to check what is working.

Any plans to update the supercapacitor footprint to something like the DSK-3R3H204T614-H2L?

-------------------- Tech Support Tips/Troubleshooting/Common Issues --------------------

High Altitude Balloon Projects

The Venus GPS is good for High Altitude Balloon projects. It was recommended by one of our engineers that launched a HAB. Under page 3 of the datasheet [ http://cdn.sparkfun.com/datasheets/Sensors/GPS/Venus638FLPx.pdf ], it states that the GPS receiver is able to achieve an altitude higher than 18,000 meters if it is not past a speed of 515m/s. Exceeding both limits at the same time will disable the receiver. This is so that the part cannot be used in a rocket or missile under the CoCom limits [ https://en.wikipedia.org/wiki/CoCom ].

Err..does this absolutely need an external antenna?

Hello,

I only need the 1pps output for a disciplined oscillator with an external antenna because I do not catch the GPS signal inside the building. Is it possible to simply "put the power" and wait the "pps" signal with this module, or should I add a uC and write some firmware to handle the GPS?

Best regards

After some poking around with this board, I have found some quirks and bugs I'd like to share:

• The 20Hz feature is of limited use. With 100ms apart, two packets arrive back to back with absolute zero space between. This means the first in each pair is at least 50ms late. If you configure it for 10Hz, packets are properly spaced 100ms apart. This quirk is true for both NMEA and binary.

• GGA is the only message that is sent faster than 1Hz. All other NMEA types are sent at 1Hz, regardless what update rate you configure.

• SkyTraq's current document Binary Command Set totally skips the navigational output format, it only handles the binary input config messages. I had to dig long and deep to find an earlier version (1.10) that explains the format of the 0xA8 message. Highly recommended; it's more efficient in that it has all the greatest hits, all wrapped up into one packet.

• Some users on the forum has complained about a static looking nav solution, where not even the least significant digit moves in lat/lon. No GPS is that good! It bothered me too, until I found the fix. SkyTraq calls it "pinning", and is the threshold in position and velocity change that must occur before it's reported as such. By default this feature is turned off (message 0x39 turns it on/off). However, the pinning parameters must also be zeroed out, even if the feature is disabled! Bug! Use message 0x3B and set all to zero. Now you will see the normal "random" drift. You may also want to check out message 0x3C and set car or pedestrian dynamics, for optimal filtering.

- Ebbe

Just wondering where the 0.2F supercap as stated above in the description is in the related products. Thanks!

Hey, for some reason they took the binary navigation output (ID: 0xA8) message out of the Binary Command Set documentation. This message can be found in the version 1.10 of the document on this page: https://www.sparkfun.com/datasheets/GPS/Modules/AN0003_v1.4.14_FlashOnly.pdf (accessed from the GPS-09133 product). Since this is arguable the most important message, it is strange why it would be removed from the documentation. Others may find this very useful, as it was VERY IMPORTANT to me, maybe you (sparkfun) could make a note and provide a link.

Thanks!

Hi folks!! i though this awesome GPS module was retired!, is good to know there's a new, improved product. i have my own (old version), working at 115200bps and 1Hz samplig rate for testing. o wrote a routine that can send commands into the unit. i send a restart command into the module, the module "should" send me back an ACK message, but, i get a completely diferent message from the especified in datasheet (same size of ACK, NACK, but 2 or 3 bytes different). does anybody have made applications like mine, that could help me?

in my opinion, this module is simply awesome and cheap ($60 with shipping to Colombia). i can get 3D fix positions inside my house, away from windows or doors. the only thing you should take care is the antenna. GPS-00177 antenna tends to brake in place where cable gets into the shield. some epoxy fix that "issue".

Hi I have a couple questions that don't seem to be explained here.
1) How is the firmware updated/changed? 2) whats the difference between the firmware versions posted. from what I can guess the standard version will log to SPI still. The internal logging logs to the internal flash. But what does "high dynamic range" really mean in this context? and how do you define a sharply turning vehicle? 3) what is the difference between booting from FLASH and ROM? Is there a different "standard" version that is non-erasable? if so what does the rom firmware do differently?

Hi Guys,

I have just GND and 3.3V connected and am getting nothing on the PPS pin. I am waiting for the GPS lock (NAV pin / LED flashing)

Have tried with a 1k pulldown and without.

Serial data from GPS on TX0 / RX0 is working fine.

I have continuity between the solder fillet on pin 40 of the chip and the PPS pin on the header.

I just want to quickly check there is not a firmware setting or something I should try before I get out the flux and try hitting the pin with the soldering iron.

hi there,

i'm writing you to understand something : 1_i need a gps to realize a wearable device, i just bought this one and i would like to be sure about which kind of configuration (in your opinion) i should use for have battery saving and good performances. To be more precise, i will use this for sport activity. 2_i would be grateful if some of you have some arduino sketch (or better an discovery ST program) to drive such GPS. It would be very fast for me to implement and run the GPS 3_the better way to connect it to have the best performance from it and battery savings at the same time.

thank a lot folks

rik

Can anyone tell me what the CLK pin does? I am using this just to get the GPS time. Does that pin output time or is it used for something else?

I've upgraded to this GPS module. I do not get the NEMA GLL line. I get the GGA, GSA, GSV, RMC and VTG. I can certainly use the info from the GGA but my code was parsing the GLL when I was using a different GPS. Is there some setting that I am missing to get the unit to output the GLL info?

Where is the ultracap?

For those wanting to buy this GPS in near sea-level areas, the GPS altitude bottoms out at 27.4 meters. I had a couple dozen of these for an experiment in Florida, and they all reported 27.4m of altitude. Actual altitude was near 5 meters.

Hi I just purchased this GPS module and I can not configure at all. I would like to update it update rate but am unable to. I have been using the standard code found on Simon Monk's site to view GPS messages at 1Hz. But I am unable to use the SkyTrack GPS software for anything other than reading. When I try to update any settings on the Venus chip I get an error saying "Target doesn't replay please power cycle target". Am I missing a serial command so that the software can communicate with the GPS chip? I'm pretty new at using Arduinos, I apologize if this is a simple question.

Hi, my Venus GPS don't work very well. It's syncronized with GPS signal because the LED is flashing, but I have any signal on Tx Pin. Do you know what I can do ? Is it dead ?

Thanks.

Can you suggest somewhere to source the Skytraq chip on its own? I'd like to integrate it into a project where size is critical

Will this work at all without connecting antenna? If no, which antenna is recommended?

I watched the AVC2014 today, and it has reinvigorated my DIY project mode. I am now looking at the Venus GPS module to make my own vehicle. My question is, are the commands from the Binary Command Set transmitted to and from the Venus through the UART port? Or is it a combination of UART and one or both of the other two synchronous serial ports?

Hi,

Does anyone knows what is the current rating for pin 18 or VBAT?

I'm having some accuraccy issues. The latitude measurement is off by about 0.02 minutes. Although this is not very wide of a margin, it may not be suitable for some of the applications I had in mind. Has anyone else faced this issue? (EDIT: other weird things are happening now. I left it for about an hour without moving it. At the beginning of that hour, the minutes measurement was 0.0068 less than it is now. Can anyone else relate?)

running 38400 baud. Using SkyTraq trying to increase up date rate, which I can for RMC. However cannot get update > 1 Hz for VTG.

tz states "RMC, GLL, GGA, VTG are all sent at the 20Hz or other value but can be throttled with another setting. "

Please advise what the possibilities for "throttled with another setting" might be.

I see a comment explaining an issue someone was having going to 38400 baud. I wonder if I am having a similar issue only I can make 57600 work but not 115200. When I set to 115200 using the GPS viewer the gps goes to 115200 (as evidenced on a scope) but I cannot ever again establish communication until switch to boot from ROM and start over. Which by the way seems to work (boot from ROM) unpredictablly, but maybe thats just me and not the point.

I am using a software serial port and wonder if going across the 65535 boundery is an issue...or if there are any other ideas.

Here is the test code i use:

 #include <SoftwareSerial.h> 
 SoftwareSerial GPS(10,11); // 10 is RX, 11 is TX
 void setup()
     {
     Serial.begin(9600);
     GPS.begin(57600);  //57600 works  115200 does not work
     }
void loop()
    {
    if(GPS.available()) Serial.write(GPS.read());
    if(Serial.available()) GPS.write(Serial.read());
    }    

Hi everybody, I have a little auestion: how can I enable the EGNOS functionality ? In the GPS viewer and configuration software is possible to enable only WAAS, but here in Europe there is EGNOS. May there is a special firmware for the Venus ?

Thanks in advance for your replay,

Alessandro Rossi.

This unit has worked well for me, but it does have a hardware quirk. I have found that if the PPS output line has any kind of load on it, the GPS won't always start. I finally had to tie the PPS line to logic through an NPN transistor, and that seems to have made the PPS reliable. I tried passing the PPS signal through the level converter breakout, but the FETs loaded the line too much and the GPS would fail to boot. Anyway, if you experience random startup issues, you might look at the digital output lines, to see if this is the same issue I encountered.

Hi guys, I bought this GPS reciever a while back and I am going to use it on a formula student race car.

I get it up and running and I am able to recieve GPGGA NMEA data at 1 hz update rate using the TX RX interface. The problem is that I want it to update at 20Hz, and I have tried to configure it using the "Binary Command Set" document. But it doesn`t reply at all, which is a bit troubling.

The command I have tried to use is: Configure Serial Port: A0 A1 00 04 05 00 05 00 05 0D 0A.

Any help would be awesomely appreciated.

The modules I recently purchased came with firmware version 2012.7.10. I installed the firmware on one module from this page that turned out to be older (2011.10.21). I would rather have both with the latest firmware. Anybody have Venus firmware 2012.7.10 or newer? Thanks!

The binary commands should be the same for this and your other Venus GPS (GPS-10920), right? I've got everything working on the other one, but with this one I can't get the baud to change using the same binary command.

Hi everyone. I have a question about active antenna. In datasheet is shown that active antenna is hooked up to power supply 3.3V and connected to input pin RFIN pin. I need to use an active antenna with power supply 5V. Is the RFIN pin 5V tolerant?

It does work whit the PRT-00449, i get the NMEA signal in my terminal on the computer but the GPS can't get a fix position. I have tried outside whit clear sky but wont work. I can't connect to GPS Viewer either. I have also coupled the Rx to the PRT-00449 now but that didn't help me to connect to GPS Viewer.

I am using Antenna: Antenna GPS Embedded SMA, GPS-00177

Could that be the problem or what else could be wrong? Need to found out so i can order more whit confidence. /Robin

I have been testing the Venus GPS tonight, I currently have it running. However I was having issues with it for several hours which i tried to figure out what was wrong with it. It would turn on with the LED only turned on very dimly. I eventually figured out that it was because of my bench power supply. My power supply voltage ramps up relatively slowly when the output is enabled. The Venus does not like to be started with a slow supply. If I disconnected it and plugged it back in with the supply turned on the GPS starts fine. It may be a good idea to have a power brownout protection circuit if you install the device in a situation it may experience brownouts.

I have been testing the Venus GPS tonight, I currently have it running. However I was having issues with it for several hours which i tried to figure out what was wrong with it. It would turn on with the LED only turned on very dimly. I eventually figured out that it was because of my bench power supply. My power supply voltage ramps up relatively slowly when the output is enabled. The Venus does not like to be started with a slow supply. If I disconnected it and plugged it back in with the supply turned on the GPS starts fine. It may be a good idea to have a power brownout protection circuit if you install the device in a situation it may experience brownouts.

Hey! I can't get a NMEA signal to my computer out of this. I can see in the oscillator that it gives me a NMEA signal (differential signal).

1. I have coupled it to the BOB-11189 - MAX3232 Breakout, I have coupled like this from Venus to MAX3232: GND to GND, 3,3V to 3V-5.5V, TX0 to T1IN.
2. Then I have coupled it to PRT-00449 - RS232 Shifter SMD, I have coupled like this from MAX3232 to RS232 Shifter: GND to GND, 3V-5.5V to Vcc, T1OUT to TX0.
3. And then to the computer via RS232.

I am supplying it whit an external 5VDC.

I have tried to change baud-rate and all the other options on computer but none give me an output in the hyper-terminal. The gps gets a fix so no problem there. What can be wrong? Need to know cause need 22 of those for an application.

Best Robin H.

Any plans on getting the new Venus 8 with 50Hz update? (And maybe glonass?)

I was thinking about using this GPS with "Arduino Uno- R3 SMD". But the 3.3V pin will only support a current of 50mA. That would be to low for this GPS, correct?

I'm having trouble sending any commands to my receiver. I am using the FTDI serial converter, and connecting it to the board I can receive all the NMEA messages and see it acquire satellites and such, but whenever I try and send a command (like reset, or query version or whatever) it just hangs for a while then says it timed out. Any ideas?

Anyone have some example C code to send a binary command to the receiver?

Thanks

Just FWIW, Skytrak is putting out a new GPS module with Venus 822 chipset, check out NavSpark on indeigogo. Not clear if it will reach its funding goal though. EDIT: looks like it will happen. Maybe SparkFun can carry this one too.

Skytraq version GPS Viewer 0.4.940. Hi, on your website you're providing Skytraq GPS Viewer 0.4.833, do you have the version 0.4.940 or a newer one? Which are the parameters you need to set up in order to have the most accurate gps positioning down to 1m as described in the tech specs? Thanks in advance for help ;-)

Hi,

So I've been working with the Venus GPS module. I was configuring the pinning and the output and suddenly it stopped locking up to satellites. I then did the factory reset, followed by a reboot on SkyTraq. Now it's outputting gibberish characters and not responding to any queries or anything. When I try to flash the stock firmware it says, "target doesn't reply, please power cycle the target". How do I do that?

Thanks

These work really great for positioning. I wanted to use it, to get an exact time, but this seems to be impossible. The 1PPS pulse is perfect and very exact, but the binary as well as NMEA timestamps are shifting by up to 1 second. This makes it impossible to assign the exact seconds to a 1PPS pulse. My Logic analyzer shows, that sometimes the timestamp is around 100ms to 500ms late (would be ok I guess), but then it is 500ms to 1000ms earlier, then the actual time. To be precise: After each reboot, the modul seems to have a different time offset to the actual time.

Any help as to how I can assign the exact time to the pulses would be much appreciated. Im currently guessing, that this is not possible with a gps module.

Hi, i have connected the Venus GPS to my Arduino UNO, with 3.3v pin to 3.3v power supply, GND to GND and Tx0 pin of Venus GPS to RX pin of my arduino UNO. ( same as the tutorial of Simon Monk). however, this is what i get from the serial monitor : Lat: 0000.0000N Long: 00000.0000E. Anyone know why? do i have to connect 3.3v to VBAT too and maybe a second GND is needed too?

Hi, i connected the Venus GPS to my Arduino UNO, 3.3v to 3.3v,GND to GND and Tx0 from venus to Rx pin of my Arduino UNO.(same as the tutorial from Simon Monk). and i get the following result in my serial monitor : Lat: 0000.0000N Long: 00000.0000E. can anyone tell me why? do i need to connect Vbat to 3.3v and a second GND too?

I'm looking to build a vehicle speed detection application.... will this give 20 speed samples a second? Can someone confirm? Any other choices?

In my lab I have a 5V, 40dB GPS antenna installed. Can I use that as an antenna for the this GPS module? Will I need to make any adjustments to the connections (any circuit elements or circuits I might need to impliment) in order to get it to work? Please help me out...

"There are even pads on the bottom of the board for the 0.2F supercap (not included but you can find it in the related items below),",

This is no longer in whatever is below.

Does anyone know how to use the Nav Lock indication? Does it simply output 3.3VDV when locked?

Does anyone know where I can find info on the nav lock indicator? Does it simply output 3.3VDC when a lock is acquired?

As a request for the future. Do you think you guys could make a breakout for this chip in a PCB Module (exposed pads on the edges of the PCB) type arrangement? To be able to solder a breakout PCB for this chip straight onto my custom board, rather than using pins, would be great!

I'm having a curious problem. I'm trying to connect this guy to a Byonics TinyTrak3 for a HAB project. The tiny track only understands NMEA0183 in RS232 and 5v TTL, so I connected a 5v-3.3v level converter to the GPS. I'm able to connect it through a max232 to a serial port and use the software to configure it. that works perfectly fine, and I get a signal lock and an accurate position in no time. Also, the tiny track seems to be working as well, I can configure it, and it transmits packets with my callsign. After making sure I configured the tiny track to accept TTL signals, I've tried to connect the two. The light on the GPS is blinking, but I see no position info in the transmitted packets. I've quadruple checked all the pinouts, even recreating the connections on a breadboard. I've run out of ideas, maybe this is a better question for Byonics, but I'm not sure which end of it has the problem.

Does Sparkfun have any GPS antenna compatible with this board?

Hi,

is it possible to operate with regulated 3,6V? The Datasheet of the Venus638FLPx says that it is possible but on your webpage you say it ist only safe up to 3.3V.

Thanks, Michael

Hello, I have one of these about 6 months old. I am using the example tutorial from Simon Monk above. My GPS gets a fix, and the red lights flashes.

My issue is that it seems as though I do not get regular updates without physically touching the unit itself. And when I say touching, I mean I have to actually be putting a little pressure onto the SMA connector, like it has a dodgey connection to the board or something like that. BUT the whole time, the unit itself still has a fix.

I am not sure where to look for ideas? I have connected a set of header pins to the unit, and they are all ok.

Example output here: Lat: 2733.0388S Lat: 2733.0388S Lat: 2733.0388S Lat: 2733.0388S Lat: 2733.0388S Lat: 2733.0388S Lat: 2733.0380S Lat: 2733.0376S Lat: 2733.0367S Lat: 2733.0369S Lat: 2733.0370S Lat: 2733.0375S Lat: 2733.0381S Lat: 2733.0389S Lat: 2733.0390S Lat: 2733.0391S Lat: 2733.0390S Lat: 2733.0393S Lat: 2733.0394S Lat: 2733.0394S Lat: 2733.0394S Lat: 2733.0394S Lat: 2733.0394S

Also further to this, the Direction can report all over the place. Without any rotation, it can go from 17deg to 170deg to 317deg. Is this normal?

I couldn't find a maximum current draw for the RFIN pin on the datasheet. For my application I'm going to need the GPS antenna about 100m away from the GPS board, which will probably require a high power antenna, or an inline amplifier. I have enough power from my 3.3v power supply, but will I damage the RFIN pin if the antenna circuit is drawing around 50-80 mA?

These chips are great but I'm still having a bit of trouble sending commands to it. I want to send a hard reset with my own lat/lon values but can't seem to find a properly defined method for doing so. Some people suggest sending the whole string in a write, others write an array of decimal values. Also, since these are part of the binary message set, is it necessary to send something to the chip BEFORE I send my reset (or another command) to put it in to this mode.

A bit of (working) code would be helpful.

I'm using mega pro 3.3v, hardware serial.

Cheers

Ian

Is the max altitude still 18000 meters if the chip is going slower than 515 m/s?

what i've done so far:

connected Venus Vcc to 3.3V, Vbat to Vcc, the 2 GND to GND, Tx0 and Rx0 to Rx and Tx of the FTDI 3.3V breakout board respectively. Open skytraq 0.4.833, its spitting out NMEA messages but i'm getting position fix unavailable.

Did i do anything wrong?

P.S: 3.3V step down from a 9V battery using lm317, got this for the antenna : GPS-00177

I was wondering if anyone else was having a lot of issues getting this gps to get a fix. I'm using it in a quad-rotor I'm working on but can't seem to get it to lock onto anything. I hooked it up to 3.3v via a atx power supply and then used a ftdi cable with the grounds tied to get the information back to my pc and left it for probably about 4 hours while I watched tv and it still didn't manage to get a lock on anything. Wondering if anyone had any advice. Thanks!

Hi all. I'm having trouble getting any serial output from this board at all. Straight out of the box, I connected GND, 3.3V, TX0, and RX0 to a 3.3V FTDI, and I see no incoming serial at any baud rate. When I use the GPS Viewer, I set the appropriate port, 9600 baud, and click "Connect". However, nothing happens after this. If I click on any of the commands, it says, "Please connect to sky traq gps." Any ideas?

I understand that I need to notify the Venus board to use a 20Hz update rate, but do I need to do that every time it is powered on?

I understand that I need to send a command to the Venus chip to get a 20Hz update rate. Do I need to do this every time that the device is powered on?

It seems you have designed the part with the SuperCap wrong.

Look at the datasheet on page 12. It shows you should have the resistor in series with the battery/supercap only, not from the diode to VBAT. This will cause the a 45s delay until VBAT is above 1.5V and the chip can function properly.

Is it possible to get this board with an MCX connector, or, at least, without the SMA connector?

Slow updates -- We very much like this GPS, but it does not seem to be updating its fix quickly. We've set the NMEA output rate to 20 Hz GGA, and the output does not change rapidly unless the unit is moving fast. We've checked and pinning is disabled. We have tried both car and pedestrian modes. We also updated the firmware to the high-dynamic range version. It appears that although the messages are streaming fast, the actual position is updating very slowly, perhaps on the order of several seconds per fix. Even walking around with the unit does not induce rapid motion.

Can i use this antenna https://www.sparkfun.com/products/464 with Venus GPS ?

Any idea if this supports RAW GPS and Ephemeris data outputs through the Skytraq binary?

Hello people in Sparkfun! I recently bought this gps but i am having issues with it getting a satellite fix... I am using the gps, an Arduino UNO and the Antenna GPS Embedded SMA. I am getting the same reads always(Lat: 2400.0000N Long: 12100.0000E) and the LED does not blink. For some reason I can not get a fix outside. In my serach for answers found out that the VBAT and second GND must be connected as well so I did but I still can not get good results. I would appreciate your help!

I want to log Ephemeris data (or pseudo range, satellite position , etc.)to calculate the position using my developed algorithm. How can I do that?

My device reboots after removing the soldered jumper for flash-boot.

How can I update firmware ?

My Venus GPS cannot boot because of power failure during firmware update.

How can I recover my GPS?

I am working on upgrading a self guided projectile to include GPS does anyone know how many Gs this board can handle?

Hi, I was wondering if anyone else have had issues with ridiculously long TTFF? My unit is taking at LEAST 4 minutes, but frequently doesn't even get a fix within 1.5 hours. Is there a specific way that the module needs to be configured?

Everything is factory default settings, and the only pins connected are 3.3V from the Arduino straight to + and VBAT, GND from Arduino to GND on the board, and TX0 from the board to the Arduino.

TTFF is no where near 30 seconds :( I've tried by a window, and sitting outside at various places on my campus.

I have a weird problem with my Venus GPS and embedded antenna that I got last week. After I hooked it up, found it in skytraq I get a lot of data. The thing is that the Latitude and Longitude data I get is around 40 miles wrong? Have anyone experienced this before? The only problem I can see is that the time on the gps itself is wrong. Around 2 hours? Can I fix this? or is it broken? Thanks

Is there any off-the-shelf firmware that provides a simple i2c interface to access position / accuracy information? I'm familiar with UART / NMEA sentences, but the micro I'm using (Zigbit) has a shared UART / SPI which I'd prefer to avoid using...

1-What the flashing light for?? Sometimes it was solid and sometimes flashing..Didn't seem to correlate to a fix 2- The SuperCap was quite hard to solder in. Didn't know if the negative solder should touch the rim of the supercap or just the foot 3-for $50 you would think it could have been attached to a shield or some kind of anchor 4-bought a similar looking magnetic antenna at cutedigi..seems to work but no feet like the SF one

We purchased this unit for use in a robotic rover, but at present we cannot effectively connect to it. Here is what we've tried so far: 3.3 V and ground connected to the appropriate pins, and an SMA antenna is attached. RX0 connected to pin 3, TX0 to pin 2, and common ground connected to pin 5 of a serial cable plug. Connecting the power causes the red led to light continuously, and then blink at ~ 1 Hz after a brief period - everything looking good so far. However, when connected to a computer, we are unable to get readable data. Using either a serial cable or serial-to-USB adapter under windows or ubuntu with either the provided GPS viewer or serial connection software, we get the same result: the device outputs repeated, random characters. It is clearly device output, as it is not present when the device is off and starts when the device is turned on, but it does not become human-readable at any baudrate. The provided GPS viewer shows the gibberish characters, and using the "scan ports" "scan baud" or "scan all" functions report that there is no skytraq gps connected.

There is exactly one setup that has been able to provide good output: connecting via the serial monitor on an attached arduino uno, as described in the tutorial link at the bottom of this product page. This outputs relatively accurate lat and long data. This is, however, not a practical setup for our project, and it seems to indicate that the data is fine, but there is just a serial connection setting that is incorrect. The arduino sketch connects via the softwareSerial library at a baudrate of 9600. Using that speed when connecting by other means produces only gibberish. Any input on what setting we are missing or other insight into the problem would be greatly appreciated.

My son and I have a Venus GPS connected to an Arduino UNO and operating. We have the code running and returning the desired info in the serial monitor. We would like to increase the update rate but can't get the SkyTraq software to communicate with the GPS. It appears to connect and displays proper info in the message window but nothing else appears and none of the changes we attempt to make are sent to the GPS. We're kind of new to this so any help would be appreciated. Thanks!

I've noticed with the supercap it will draw 100uA or more while charging until the cap is charged from an external battery source. In this case my motorcycle acquisition system (harleyhacking.blogspot.com). I wanted to keep that alive while things were sleeping by using the MC battery, but for the moment (while it is going to be plugged and unplugged) not have it forget everything.

Is there a lithium manganese or whatever that will fit on the same solder pads?

Reply doesn't work for firefox, this is a reply to JohnGalt

info@skytraq.com.tw is who to contact for the EVK.

Last year:

We offer Venus638FLPx-EVK, consisting of active antenna + evaluation = board + USB cable + evaluation utility software + 3 samples, for $99. = Additional sample is $20 each. FedEx shipping to use is $30. Our minimum = order amount is $200.

I think their GLONASS EVK is also $99.

Also someone asked about 20Hz - yes it is as accurate 3m (or even 2.5 with waas but that isn't common), but the output is staggered, so although the TPV is accurate, the latency of the data from the event varies for each packet iand is often more than 200mS late. On my motorcycle logger, I read the PPS and sync a millisecond counter so I know where the UTC second is in the non-gps data.

We integrated this board to our own PCB design. Now we are thinking of integrating the chip itself. Did you guys have to set the chip up to be fixed to a 1Hz default? In other words: If we would integrate the circuit of this module into our own pcb design, will this stuff just work?

One note - at 20Hz with one of the powered antennas, even if not locked (or maybe because since searching uses more), it pulls about 100mA. That ends up being about 330mW, not the 67mW it claims. I haven't tried it at 1Hz. Now I know why my regulator is getting so hot. The powered antenna uses about 10mA, I don't know about the LED.

It's awesome! I just received it today and works very well and faster. Great product

does anyone has arduino code to read the co�rdinates and calculate the heading? i would love to see some example code!

I have two problems with my Venus Board which I suspect to be connected.

First of all my setup:

I have disconnected the BAT jumper and am feeding the Venus (both VBAT and 3.3V) from a 3.7 V LiPo battery which works just fine (to be precise I'm using the PackageTracker).

Problem nr. 1 (which really isn't one but it occurred to me as strange): When I measure the resistance between the BAT jumper pad, which is connected through the diode and the resistor to VBAT, and the actual VBAT line (either pin directly at Venus module or pin header) I don't measure anything. Since there is a diode involved I tried both directions which didn't help.

Do I have a faulty device?

Prblem nr. 2 (the real problem): I want the Venus to reset to default settings the moment I remove power from both VBAT and 3.3V. So when I configure it I write all the settings to SRAM only (not to flash!!!) but when I disconnect the power source it keeps the settings nevertheless (even if I disconnect all the wires).

Is this because of capacitor nr. 5? If it is because of capacitor nr. 5, can I just remove it?

SURPRISE! - I should have looked more closely, but the pinout has changed.

I have the evk and have been in contact - I should try the SD card on the SPI

http://www.dl9sec.de/venus6/venus6.htm

Will this board tolerate 5 volt serial from a 5 volt Arduino?

Can anyone recommend ways to mount this unit? What are some common methods for these small boards with no mounting holes?

I'm having some weird problems with this board that I cannot explain, or eliminate. Specifically, when I set the unit to enable WAAS, output only GGA messages and report at 10 Hz, the unit sometimes fails to lock onto any satellites. Sometimes it may eventually start to output data after about 20-30 minutes but, at other times, it stays in a state where it cannot get a position lock even after several hours with an unrestricted view of the sky.

Giving the unit a factory reset command, followed by a power off cycle seems to put the unit back into an operational state. However, when I then try to switch back on the WAAS, GGA-only and 10Hz options, the unit will eventually start to show the same problems again.

I have now observed this same behavior in two different GPS modules using the Venus chip set, so a hardware problem is lower on my list than a software, or config issue. But, I'm not sure what tests to try next to isolate and diagnose the problem. has anyone else seen something like this?

Wayne

Is it just me or does the zip file contain a corrupted .brd file?

http://www.dl9sec.de/venus6/venus6.htm

It would probably need a few more pins bonded out but you can add uSD card logging capabilities

can you update the images to show scale or pin distances please?

Build more. Why didn't you keep the 4 main pins GND, TX, RX, 3.3V in the same location as the superceeded version?

http://www.sparkfun.com/products/9133

These used to cost a lot less. What happened?

Does SF offer the inductor used on the bias tee somewhere on the site?

Wow...you snooze you lose! Any more of these on the production line?

Are you sure that the RF trace that goes from the IC to the SMA connector is the correct width? Looks to me like if you had used the microstrip model for calculating that trace width, when what you have is mostly behaving as a coplanary waveguide with bottom ground plane (CPWG model). Using 1,5mm FR4 PCB material the trace should be about 0,8mm wide and be separated by a 0,16mm gap to the upper ground plane to get a 50ohm line, using CPWG. What you have looks more like a ~3mm width, which is the 50ohm width for a microstrip model, which doesn't have an upper ground plane.

Anyway, the trace impedance here doesn't really matter that much, because the length of that minute trace is much shorter than the wavelength of the 1.57GHz GPS signal, but I think you should correct this mistake for future versions of the board.

Hey, just a quick note. I ran the quick_test from the LS20031 GPS tutorial (using my LS20031) and GPS Viewer from this page, told the SkyTraq to listen to my Arduino COM port (COM7) and it worked! I know this will not help everyone with the LS20031 (and the Arduino 1.0 IDE)- but at least it nice to know something works.

Damn! I've just made a new PCB design with the pinout of the old breakout board. The new module is 100% INCOMPATIBLE with the old pinout! Why for heaven's sake didn't you leave at least GND, 3.3V, RX and TX at the locations where they used to be? I want the old design back! I was just ready to order 10 modules and now this...

Hi, I received this one, but it seems, its old PCB from retired product http://www.sparkfun.com/products/9133 with the new 638 chip. Module is working, but I was little bit confused - I checked this new one schematics and I could not find jumpers on board. Then I found old one schematics and everything was clear.

How's latency on the SPI write on these devices? Guess I can scope it out when it gets here, but if anyone knows... Eases the computational load a bit if I can simply writeback to MCU through SPI instead of parsing NMEA..

Are there plans to make another SPI logging version like your old Venus modules had? I have the logging one, love it, and this board looks like a well thought-out set of improvements! I know i can do the SPI flash myself, but having it right there was a nice bonus.

Suggestions for SparkFun for this and other GPS boards:

1. Use a thinner board material (0.031" versus 0.062"). This would allow you to use a more manageable width for your 50ohm RF microstrip.

2. The GeoHelix antenna is amazing and it would be cool if the board could be made such that either that antenna or an SMA connector could be attached. They both use a similar footprint and can be made interchangeable.

Otherwise, this board looks really great. Do we know if special firmware is necessary for the unit to be used at high altitudes?

I have the SDK and have been using their EVB and this chip is incredible. It is basically a Sparc. There are limitations - the modifiable firmware was (last I have) 10Hz only. You can use the SPI to log to an SD card. The second serial port isn't really interrupt driven so there can be problems. But it is worth looking at.

This revision sounds great! I kept soldering a diode and having a Lithium cell hang off it - the supercap should be much better,

The supercap is to maintain the time and epheremis for a warm start.

It supports AGPS - same as the earlier one (my sample code should be in the fora). AGPS is in flash.

20Hz can overrun some mapping programs, but I've used it to log my motorcycle trips last year. 20Hz gives lots of detail, every few feet even on the freeway. Curves on the cloverleafs, not polygons. With a good antenna (I use Sparkfun's with the EVB) it can lock on quickly and stays locked.

I have used the suggested capacitor before as a VBAT backup for a different GPS module (Inventeksys ISM300F2-C5.1-V0004) and it works well. If you plug in the numbers (3.3V, 0.2F, 200ohm internal resistance, 9mA charge) into this website and take the results as charge time instead of discharge time, it says it would fully charge in 20 seconds. If you run it the other way, with 10uA discharge down to 1.5V, it does say the cap should provide greater than 7 hours of backup time. You can see some pictures of PCBs I created with that capacitor and the Inventeksys module here. I had originally used a coin cell but this capacitor is smaller, lighter, and just worked better.

Sparkfun needs to give us more information about the I2C part. Yeah you go over to the www.Skeytraq.com.TV site and basically it's Hu? {http://www.skytraq.com.tw/news/news2010-11-19.html } And when you say custom firmware that makes it sound like it's for the PC only. Sparkfun needs to elaborate on this more please.

is the capacitor for backup (hot start) or running the GPS or can it be used for either? I'm guessing backup since the cap is rated 10 micro amps.

How long does the cap take to charge after complete drain? Is there a way to detect the cap charge level? Has the 7 hours been verified? It seems low for standby.