Problem with nmea_serial_driver
Hi, I'm trying to use the nmea_navsat_driver stack with a TOPCON GPS unit. However, the nmea_serial_driver starts and issues the following warnings:
$ rosrun nmea_navsat_driver nmea_serial_driver _port:=/dev/ttyUSB4 _baud:=115200
[WARN] [WallTime: 1410482892.574839] Received a sentence with an invalid checksum. Sentence was:
[WARN] [WallTime: 1410482893.088193] Received a sentence with an invalid checksum. Sentence was: $GPGSA,M,3,16,32,20,11,22,01,,,,,,,2.71,1.81,2.01*04
but then goes quiet and doesn't publish any data across the fix and velocity topics. Via a serial monitor I can confirm that the NMEA sentences are being published correctly with the correct checksums. The above two messages seem to be just startup errors.
However I can get the system to work with nmea_topic_serial_reader combined with the nmea_topic_driver on the same settings. However in this configuration it doesn't issue velocity information (from the NMEA RMC message).
Any suggestions on how to get the nmea_serial_driver to work?
Peter, are you still having this problem? If so, can you file an issue on https://github.com/ros-drivers/nmea_n... so we can get it sorted out. There shouldn't be any difference between running with topics or without, so there's probably a bug somewhere in here that I need to fix.