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+title:Serial GPS data reading utility
+keywords:gps,serial,uart,tty
+
+# Serial GPS data reading utility
+Serial usb gps deviceses can be used trought serial consoles
+or some other libraries. From shell need some basic configuaration
+at begining to use serial device from shell. This command
+provide simple way how to do it.
+This code opens /dev/tty* device, setup baud rate to 4800
+and outputs line by line recieved data.
+When device connected ther could be that is not in NMEA mode
+it could be switched with:
+
+```
+gpsctl -n /dev/ttyUSB0
+```
+
+Then you can connect with it with some serial terminal(dont forget baudrate
+could be 4800 or 9600):
+
+```
+minicom -D /dev/ttyUSB0
+```
+
+Now we can use our gpsr utility
+
+```
+./gpsr -d /dev/ttyUSB0 -c 0
+./gpsr -d /dev/ttyACM0 -c 1
+```
+
+NMEA format is csv like and it easyly can be used from shell. Here is
+exmple how it looks:
+
+```
+$GPRMC,123519,A,4807.038,N,01131.000,E,022.4,084.4,230394,003.1,W*6A
+```
+
+Where:
+RMC Recommended Minimum sentence C
+123519 Fix taken at 12:35:19 UTC
+A Status A=active or V=Void.
+4807.038,N Latitude 48 deg 07.038' N
+01131.000,E Longitude 11 deg 31.000' E
+022.4 Speed over the ground in knots
+084.4 Track angle in degrees True
+230394 Date - 23rd of March 1994
+003.1,W Magnetic Variation
+*6A The checksum data, always begins with *
+
+Get time from GPS
+
+```
+./gpsr -d /dev/ttyUSB0 -c 100 | stdbuf -o0 grep -w "GPRMC" | cut -d',' -f2
+```
+
+## REQUIREMENTS
+GCC C, minicom, shell, GPS device
+
+## TESTED
+I have tested everything with GPS devices BU-353 and with
+some device that havenot any visual marks but have chip
+from u-blox manufacturer.
+
+## COMPILE:
+
+```
+gcc buf.c -c
+gcc serial_tty.c -c
+gcc serial_tty.o buf.o gpsr.c -o gpsr
+```
+
+## TODO:
+there could be added baudrate set as params
+loging in csv,xml,json files
+make longterm test for stability
+
+
+## Links
+http://en.wikipedia.org/wiki/NMEA_0183  
+http://www.gpsinformation.org/dale/nmea.htm  
+http://home.mira.net/~gnb/gps/nmea.html  
+http://linux.die.net/man/1/minicom  
+
+## Downloads
+gpsr.tar.gz - 3KiB -
+http://archive.main.lv/files/writeup/serial_gps_data_reading_utility/gpsr.tar.gz
+