Can't establish connection between GPS and Jetson Nano

I connected my GPS module to 5V, Ground, Tx/Rx pins according to pinouts and I still can’t read any data using cat /dev/ttyTHS1. All my pins are correct, my GPS module use baud rate of 38400 so I set ttyTHS1 to 38400 also using “sudo stty -F /dev/ttyTHS1 38400”. Am I missing anything? Thanks

Is the signal level 3.3V for your GPS? If not, then it needs a level converter. Also, if a serial terminal is already running on that UART, then you’d need to disable this. Check the output of “ls -l /dev/ttyTHS1”, and if the “group” is “tty”, then you are in conflict with serial console; if the group is instead “dialout”, then you are good to go.

A typical disable would be:

sudo systemctl disable nvgetty.service
sudo systemctl stop nvgetty.service

Hey, sorry for the late reply. I did use both 3.3v and 5v pins to try if they would work and neither really did. When I did “ls -l /dev/ttyTHS1”, I got the output “crw-rw---- 1 root dialout 238” which should be ok if I am not wrong. I already disabled nvgetty.service and right now, I dont know what I should do. Thanks for the reply.

This sounds correct. Is there any possibility of putting either a logic analyzer or just an oscilloscope on and seeing what happens with TX and RX?

I unfortunatelly do not have any of those :(

One possibility for a partial test is to use the Jetson to talk to itself in loopback mode. Basically you’d connect the UART TX pin to the RX pin (and if using flow control, then also CTS to RTS pin). Then you’d use a serial terminal program, e.g., minicom or gtkterm, and simply type text in. If the text echos back to the terminal, then it works. Try that with the serial terminal program using the same settings you would use for the GPS setup. This won’t test a problem between Jetson and GPS, but it will say if the Jetson side works as expected.

I can’t write on either minicom or gtkterm, does that mean there is a problem with my ports? I feel like im missing some basics so I will go through everything I’ve done. I disabled and stopped nvgetty.servicei set baud rate accordingly and tested with both voltage levels. I feel like this problem may be on Jetson side.

Was this loopback? If so, then that is a problem. Make sure also that you do not use the CTS/RTS flow control. Or also short CTS and RTS. All voltages should be 3.3V.

I gave up and connected it through a gps, still, thanks a lot.

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