Apologies for the slow response but I'm experiencing difficulties obtaining a log for the echo-sounder. I can readily cat /dev/ttyS0 and get a copy of the main gps log but all attempts to get an output log for the echo sounder fail - cat terminates after approximately one line of output and no usable log is written. I've tried swapping the echo-sounder output, which is normally connected via /dev/ttyUSB0 to the serial port ( which cat's fine with the output from the NMEA gps) but the result is the same; 1 or less lines out output then cat terminates. However, both the Windows software running under Wine and OpenCPN running natively will display the echo-sounder sentences with no problem.
I've even tried using gpspipe -r but that then attaches itself to /dev/ttyUSB0 and displays no data ( only ECGLL and SDDBT sentences on this port) This in itself is strange as if I tell Opencpn to use gpsd as it's data source, it appears to use the data coming in on /dev/ttyS0! I think the way the system starts also complicates the problem:
When I turn on boat electrics; the gps ariel and AIS receiver are powered, when I start the engine, the computer powers up. i.e. the first signals "seen" are gps on S0 and AIS on S1 When I turn on the echo-sounder, then there is an additional gps signal + SDDBT on USB0. Ideally,if SDDBT was parsed, I'd route all data through the echo-sounder and dispense with the NMEA ariel signal.
However, we're not going to get there if I can't get a usable log out of the sounder so any advice on how to achive this would be much appreciated