So i just got my brand new pixhawk + 3dr external mag+gps combo from unmannedtech, but Pixhawk doesn’t recognize GPS at all (ext. compass works fine)
Mission planner says - No GPS and in terminal under test -> gps only dots (…) are running.
GPS blue light is blinking and i tested the same gps+mag module on apm 2.6 and it worked there perfectly.
I have tested another 3dr gps+mag module and that one also didn’t work.
I have tried numerous reflashes of different firmware versions, but still pixhawk does not see GPS at all.
Cables are all fine, tested them with multimeter and tried multiple cables.
What can i do more to help debug this problem?
sorry, it seems like your GPS is bad, do you have access to another GPS module you can test with ?
if you have a USB-serial adapter, you could try to inject serial data into pixhawk’s RX pin , or check that a computer can display GPS’s TX data. This will at least tell you which part to blame.
[quote=“surndliha”] tested the same gps+mag module on apm 2.6 and it worked there perfectly.
I have tested another 3dr gps+mag module and that one also didn’t work.[/quote]
Try using a powered USB Hub and see if that helps.
I have tried using 3dr power module and backup power from the esc/bec.
If you were testing it with the same cable it can´t work, check the schematics attached. (a little small, but this forum allows only 600px)
Btw. the eagle files, listed at some of the stores below the 3DR GPS / Compass Combo (V1.2) show boardlayout and schematics of the 3DR GPS only (V1.1) So you have to find the schematics of the V1.2 first, before you are able to check wiring .
Here is a picture that shows the pin out of the GPS v1.2 and the connections to the APM, but you can adapt the information to the Pixhawk.
According to the Pixhawk Wiki
copter.ardupilot.com/wiki/common … ss-module/
“The 3DR uBlox GPS + Compass module currently works with APM:Copter version 3.0.1 (it does not work with the current APM:Copter 2.9.1b and earlier).”
What version are you using?
Pixhawk connection pinout diagram is here - copter.ardupilot.com/wiki/common … or_Diagram
So it’s like this for pixhawk: 5V,TX,RX,-,-,GND
for GPS: 5V,RX,TX,-,-,GND
So not much to go wrong - two most outermost pints are 5V and GND and TX&RX are to the 5V side. And ofcourse i have already tried swapping TX&RX.
I have tried basically every (beta/rc) version between 3.0.1 and 3.1
So i sent this pixhawk back to the shop and they sent me a new one and it works like a charm out of the box.
As expected, that pixhawk was faulty.