[REBOL] Re: Serial Communications - GPS Sings!
From: webmaster::windsweptfarm::com at: 19-Feb-2002 1:07
Dear List,
Thanks for the pointer/s.
I'm slugging it out little by little.
I have now managed to pluck an individual NMEA sentence out of the NMEA
stream and display it on the console. Sending the data somewhere else is
trivial at this point. For those that care the code below opens the com2
port in the mode you see as "read only" "line by line" at 4800/8/n/1.
The subsequent "Dave Harley" while loop checks for data pressence and
executes a second while loop to validate that the sentences are
Geographic Position
sentences and if they are prints the actual data
that trails after the "$GPGLL" identifier.
code starts--->
GPS_STREAM: open/read/lines serial://port2/4800/8/none/1
while [0 <> (length? (NMEA_LINE: first GPS_STREAM))] [if [(GEO_POS:
find/match NMEA_LINE "$GPGLL,")] [(print GEO_POS)]]
code ends -----^
My next wish is to pull the data out of the strings and do a "Z
transform" on the lat/long positions. This is where we interleave the
two numbers to wash out a bias when storing them in a linear medium such
as computer memory. When they are stored (depending upon their density)
they will follow a nested raster chaining pattern if we connected them
together on the surface of the earth.
Some of you helped withn the interleaving code for that about a year ago
and I will thank you shortly.
This data was generated by setting the garmin gps in simulation mode and
setting the speed to 100mph.
The initial position is where the machine had it's last position fix and
the destination is Garmin's headquarters in Kansas. So the data points
are a straight line vector from where I last ran the gps outdoors.
4339.015,N,07953.247,W,051936,A*30
4339.015,N,07953.247,W,051938,A*3E
4339.015,N,07953.247,W,051940,A*31
4339.015,N,07953.247,W,051942,A*33
4339.015,N,07953.247,W,051944,A*35
4339.015,N,07953.247,W,051946,A*37
4339.015,N,07953.247,W,051948,A*39
4339.015,N,07953.247,W,051950,A*30
4339.015,N,07953.247,W,051952,A*32
4339.015,N,07953.247,W,051954,A*34
4339.015,N,07953.247,W,051956,A*36
4339.015,N,07953.247,W,051958,A*38
4339.048,N,07953.247,W,052000,A*37
4339.096,N,07953.247,W,052002,A*36
4339.144,N,07953.247,W,052004,A*3E
4339.117,N,07953.323,W,052006,A*39
4339.103,N,07953.386,W,052008,A*3D
4339.088,N,07953.449,W,052010,A*32
4339.073,N,07953.513,W,052012,A*3A
4339.058,N,07953.576,W,052014,A*36
4339.043,N,07953.639,W,052016,A*36
4339.028,N,07953.702,W,052018,A*3C
4339.013,N,07953.766,W,052020,A*3D
4338.998,N,07953.829,W,052022,A*30
4338.983,N,07953.892,W,052024,A*3C
4338.968,N,07953.956,W,052026,A*32
4338.953,N,07954.019,W,052028,A*31
4338.938,N,07954.082,W,052030,A*37
4338.923,N,07954.145,W,052032,A*35
4338.908,N,07954.209,W,052034,A*31
4338.893,N,07954.272,W,052036,A*3C
4338.878,N,07954.335,W,052038,A*35
4338.863,N,07954.399,W,052040,A*36
4338.848,N,07954.462,W,052042,A*3E
4338.833,N,07954.525,W,052044,A*36
4338.818,N,07954.588,W,052046,A*3A
4338.803,N,07954.652,W,052048,A*3A
4338.788,N,07954.715,W,052050,A*3D
4338.773,N,07954.778,W,052052,A*30
4338.758,N,07954.841,W,052054,A*3A
4338.743,N,07954.905,W,052056,A*33
4338.728,N,07954.968,W,052058,A*3B
4338.713,N,07955.031,W,052100,A*3B
4338.698,N,07955.095,W,052102,A*35
4338.683,N,07955.158,W,052104,A*39
4338.668,N,07955.221,W,052106,A*33
4338.653,N,07955.284,W,052108,A*3A
4338.638,N,07955.348,W,052110,A*3F
4338.623,N,07955.411,W,052112,A*3C
4338.609,N,07955.474,W,052114,A*31
4338.594,N,07955.537,W,052116,A*32
4338.579,N,07955.601,W,052118,A*39
4338.564,N,07955.664,W,052120,A*3D
4338.549,N,07955.727,W,052122,A*36
4338.534,N,07955.791,W,052124,A*37
4338.519,N,07955.854,W,052126,A*3C
4338.504,N,07955.917,W,052128,A*38
4338.489,N,07955.980,W,052130,A*3B
4338.474,N,07956.044,W,052132,A*39
4338.459,N,07956.107,W,052134,A*36
4338.444,N,07956.170,W,052136,A*38
4338.429,N,07956.233,W,052138,A*39
4338.414,N,07956.297,W,052140,A*36
4338.399,N,07956.360,W,052142,A*3F
4338.384,N,07956.423,W,052144,A*35
4338.369,N,07956.486,W,052146,A*3B
4338.354,N,07956.550,W,052148,A*31
4338.339,N,07956.613,W,052150,A*37
4338.324,N,07956.676,W,052152,A*3A
4338.309,N,07956.739,W,052154,A*39
4338.294,N,07956.803,W,052156,A*38
4338.279,N,07956.866,W,052158,A*36
4338.264,N,07956.929,W,052200,A*3E
4338.249,N,07956.992,W,052202,A*33
4338.234,N,07957.056,W,052204,A*3F
4338.218,N,07957.119,W,052206,A*39
4338.203,N,07957.182,W,052208,A*3F
4338.188,N,07957.245,W,052210,A*3E
4338.173,N,07957.309,W,052212,A*31
4338.158,N,07957.372,W,052214,A*32
4338.144,N,07957.435,W,052216,A*39
4338.129,N,07957.498,W,052218,A*3B
