Ug-353 — Gps Driver

stty -F /dev/ttyAMA5 9600 cs8 -cstopb -parenb Now cat /dev/ttyAMA5 showed garbage. Good—data was flowing.

Still no fix in gpsd . Marta ran gpsd -N -n -D 5 /dev/ttyAMA5 (foreground, debug mode). The debug output revealed: ug-353 gps driver

The UG-353 was wired to UART5 on a Raspberry Pi Compute Module 4. Marta had written a simple systemd service to start gpsd with the correct options: stty -F /dev/ttyAMA5 9600 cs8 -cstopb -parenb Now

sudo gpsd /dev/ttyAMA5 -F /var/run/gpsd.sock But cgps showed a blank screen. Zero satellites. Sky was clear. ug-353 gps driver

Now $GPGGA sentences appeared cleanly.

dtoverlay=uart5,uart5_rx_pullup=on

Marta checked the datasheet. UG-353 defaults to 9600 baud , but the Linux kernel expected 115200 for the UART. She fixed the stty settings: