Problem With GPS
Hi all
I recently bought a Parallax GPS receiver (28146). I've hooked it all up exactly as described in the PDF documentations (GND, +5V, SIO) to my stamp. However when running the sample program i get no results. (it simply says no gps connected). I've double checked all the ports are correct and the led is flashing on the gps.
I simplified the code down to the below to simplify it and double check everything but still get no response.
Can anyone help please? Much appreciated
' {$STAMP BS2e}
' {$PBASIC 2.5}
hardware VAR Byte
firmware VAR Byte
getinfo CON $00
baud VAR Byte
baud = 188
DEBUG ? baud
SEROUT 0, baud, [noparse][[/noparse]"!GPS", getinfo]
SERIN 0, baud, 2000, noserial, [noparse][[/noparse]hardware, firmware]
DEBUG ? hardware
DEBUG ? firmware
STOP
noserial:
DEBUG "no incoming", CR
I recently bought a Parallax GPS receiver (28146). I've hooked it all up exactly as described in the PDF documentations (GND, +5V, SIO) to my stamp. However when running the sample program i get no results. (it simply says no gps connected). I've double checked all the ports are correct and the led is flashing on the gps.
I simplified the code down to the below to simplify it and double check everything but still get no response.
Can anyone help please? Much appreciated
' {$STAMP BS2e}
' {$PBASIC 2.5}
hardware VAR Byte
firmware VAR Byte
getinfo CON $00
baud VAR Byte
baud = 188
DEBUG ? baud
SEROUT 0, baud, [noparse][[/noparse]"!GPS", getinfo]
SERIN 0, baud, 2000, noserial, [noparse][[/noparse]hardware, firmware]
DEBUG ? hardware
DEBUG ? firmware
STOP
noserial:
DEBUG "no incoming", CR
Comments
The GPS should be able to get a valid signal eventually even if there's something wrong with your program. It will sometimes take surprisingly long to lock on. Try leaving it sitting with an open view of the sky for several minutes. Once you get a steady red light on the module, run your program and see what you get.
I should have mentioned that. I had left the unit in the open over 30m from any obsticals for about 20 minutes. The light turned solid red but no change to the message it returns.
I understand that means it has some lock but not enought for a fix. It was out there for over 25 min which surprised me as to how long it took.
Would it provide Hardware and firmware values even without a full lock though?
I have now got it to a solid red light but it has not changed from that in over 2 hours now. This has me rather confused
As far as I know, when it's a solid red light, it has a fix and should be transmitting data. It doesn't turn green, or anything like that.
So yes, a solid red light means you've got a fix. A green light means you've got radioactive waste on your GPS.
For correct operation of the Parallax GPS, it should not be mounted on the BOE breadboard area.
I had good success with the GPS when I had it on a servo cable that was around two feet long.
Just a thought.
Regards,
TCIII
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If you are going to send·a Robot·to save the world, you·better make sure it likes it the way it is!
Tom C thats good to know someone else found that as well. when i mounted the gps on a breadboard about 20cm from the stamp it got a fix much faster. Must be vulnerable to interferance from something on the stamp. Will try and get ahold of a longer cable to see if it improves further.