I am seeing the message "More than 100 frame errors, UART RX was disabled", what do I need to do to fix it?

If you see this message in the output from the GPS;

More than 100 frame errors, UART RX was disabled

This is the GPS telling you that it is receiving data on the serial port, but it doesn’t recognize it.

The cause is most likely due to echo being enabled on the Raspberry Pi serial port.

Echo can be disabled with;

pi@raspberrypi ~ $ /usr/bin/stty -F /dev/serial0 -echo