uBlox GPS debugging issues

[Admin]

I bought the Ublox5, but its not doing anything . . .

I'm in a basement, so assuming I don't have a signal, would it still output at least something?

Is it normal if it gets a bit warm? I'm feeding 5V regulated to its >5V pin. (it doesn't need to be regulated, I know, but it was available in my setup)

How would I know if its ArduPilot, Paparazzi, or NMEA default configuration? I told my ordering department (here at work) to get NMEA, but its possible they didn't . . .

[madsci1016]

Have you tried Ublox's own GPS tool? I believe it can read all the protocols the GPS can send. And I think if it is in Ublox binary, it has to be asked for data, so it won't stream anything out if not asked.

http://www.u-blox.com/en/evaluation-tools-a-software/u-center/u-center.html

[Admin]

And I think if it is in Ublox binary, it has to be asked for data, so it won't stream anything out if not asked.

Do you know what command to send to get it to talk to me? I sent it a bunch of random characters but no luck . . . the datasheet doesn't say anything . . .

[madsci1016]

No, I don't know it.

Try U-Center, and if it works you can reprogram it into NMEA mode. Don't forget to connect both TX and RX to the GPS from your USB to UART board. (I did)

Also, remember that funky micro plug is finicky. Make sure you are holding it together well if not glued yet.

[Admin]

Hmmmm it seems to connect firmly . . . but you mean this isn't good enough?

And does yours get warm? How do you power it?

[madsci1016]

I don't remember...

Taking SAGAR apart now... check back.

Also, I'm in Chat.

[madsci1016]

SAGAR has been on for a few minutes, the way the GPS is mounted I can only touch the side opposite the connection board.

It's warm to the point I can tell it's on, but not much hotter then that. Nothing I would worry about.

I power it off the 5V regulated Axon bus aka ADC power.

Yes, even when my connection felt firm, looking at it the wrong way would cause problems. I remember always having to apply pressure before I glued it together.

Try U-center!!!

[Admin]

I power it off the 5V regulated Axon bus aka ADC power.

Same here. It was slightly warm . . . hotter than it should be at least considering the small amount of current its supposed to use . . .

I just added some epoxy to the board to hold it together. It'll take a day to set. Should I angle the boards or keep them perfectly parallel for a good connection?

[madsci1016]

I kept mine straight.

 Did you ever try using u-center to connect to it? I'm really thinking that's the answer.

[Admin]

I kept mine straight.

 Did you ever try using u-center to connect to it? I'm really thinking that's the answer.

Not yet.

I used an Axon as my USB->TTL adapter, but no luck. My dedicated CP2102 adapter doesn't have a 5V output, so I need to figure out power to try it out. But for now I'll just let the epoxy set and get back to it tomorrow. I've been at work since 8:30am and its almost 8pm now . . .

[Admin]

Made some progress . . .

I hooked it up directly to my CP2103 from SF.

Using u-center, and after downloading the latest firmware (v6.02) from the site, I managed to get it to successfully update itself. So the connection is good.

Not even my phone can get a signal in my lab, yet this guy was able to pick up 4 satellites for a short period of time . . . then lost them all . . .

But when using the Axon it still doesn't get any data at all . . . I almost feel as if u-center transmits a connection command or something . . .

madsci, how are you interfacing with the ublox?

[madsci1016]

A regular old NMEA parser

Did you confirm it was in NMEA mode? The u-center is daunting in how many options it gives you, so make sure your changing the right params

Also, any changes you make to the gps have to be commited to flash or they won't hold through power cycles. It took me a few tries to find that out.

[Admin]

Does your 'A regular old NMEA parser' send a command before parsing?

Is the parsing done directly on your Axon?

I'm not actually parsing anything, just using the Axon as a TTL->USB adapter (input from uart 3 is output for uart1)

typical data when using u-center:
??:??:??  $GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30
??:??:??  $GPGSV,1,1,00*79
??:??:??  $GPGLL,,,,,,V,N*64
??:??:??  $GPRMC,,V,,,,,,,,,,N*53
??:??:??  $GPVTG,,,,,,,,,N*30
??:??:??  $GPGGA,,,,,,0,00,99.99,,,,,,*48

[madsci1016]

I've used it with both webbots nmea lib and my own parser, both don't send anything.

Do you get output in hyperterm usind the cp uart to usb chip?

U-center could be temp configing it into nmea mode for its own use. Have you checked the actual flash settings of the gps? When I get home I'll post my config to confirm yours is right.

My money is still on it's flash settings are not correct.

[Admin]

Do you get output in hyperterm usind the cp uart to usb chip?

yeap! that means its the Axon code somehow causing problems . . . probably some hidden bug, but I can't seem to find it . . . arg . . .


edit: SOLVED
Turns out the UART port I was using on the Axon was fried. Swapped to a different UART and it now works. Thats what I get for using a 3 year old alpha Axon version that I found in a pile of stuff . . .

[madsci1016]

Lol, when something doesn't work, start removing the variables.

Glad it works, and be prepared to be blown away by the Ublox. Night and Day over the Venus.

Also, helix antennas work better point towards the source(the sky). It will work on it's side but it works better with the antenna pointing up.