Ключ -f взял из инструкции 2 Installation Steps
1. Plug in a u-blox1 receiver through the USB interface.
2. If correctly functioning, NMEA data should be readily available using /dev/ttyACM0. Direct the application to
read from this device file. Writing to this will send data to the GPS receiver.
3. If the Linux GPS application uses the gpsd interface, start gpsd -f /dev/ttyACM0.
Перепробовал другие ключи :# gpsd -b /dev/ttyACM0
# gpsd -n /dev/ttyACM0
# gpsd -N /dev/ttyACM0
gpsd: can't bind to IPv4 port 2947, Address already in use
gpsd: maybe gpsd is already running!
gpsd: can't bind to IPv6 port 2947, Address already in use
gpsd: maybe gpsd is already running!
# gpsd -G /dev/ttyACM0
# gpsd -D /dev/ttyACM0
gpsd: can't run with neither control socket nor devices
# gpsd -S /dev/ttyACM0
gpsd: can't run with neither control socket nor devices
# gpsd -V /dev/ttyACM0
gpsd: 2.94 (revision 2011-11-16T15:52:18)
# netstat -an|grep 2947
tcp 0 0 0.0.0.0:2947 0.0.0.0:* LISTEN
$ cat /dev/ttyACM0
$GPTXT,01,01,02,u-blox ag - www.u-blox.com*50
$GPTXT,01,01,02,HW UBX-G70xx 00070000 *77
$GPTXT,01,01,02,ROM CORE 1.00 (59842) Jun 27 2012 17:43:52*59
$GPTXT,01,01,02,PROTVER 14.00*1E
$GPTXT,01,01,02,ANTSUPERV=AC SD PDoS SR*20
$GPTXT,01,01,02,ANTSTATUS=OK*3B
$GPTXT,01,01,02,LLC FFFFFFFF-FFFFFFFD-FFFFFFFF-FFFFFFFF-FFFFFFF9*53
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Идеи кончались