The software interface protocol of the software interface GPS25 board uses the US NMEA0183 ASC II code protocol, which is NAEA 0183 20 (this protocol is to establish a unified RTCM standard in different GPS navigation devices).
The following command describes the data format definition of the GPS 25 navigator, including baud rate selection, second pulse output, and RTCM definition output.
1, NMEA receives the statement
* GPS 25 input statement, mainly initialization, parameter settings pass the RXP pin
(1) ALM (Class Information) Format: $ GPALM, <1>, <2>, <3>, <4>, <5>, <6>, <7>, <8>, <9>, < 10>, <11>, <12>, <15>, * hh
Use this statement to initialize information if the backup battery on the board
<1> The total number of colors can be transmitted to the GPS board when the column is issued, and this field can be expressed or arbitrarily on the GPS board.
<2> The current number of books 20 This field can be empty or arbitrary;
<3> Satellite PRN countless 0 to 32
<4> GPS star number
<5> SV status, 17-24 bits of each column
<6> Centrifugal rate
<7> Draft time
<8> inclination
<9> Rising rate
<10> half-axis
<11> End of the location
<12> Section
<13> Recently Level
<14> AFO Time Parameters
<15> AF1 time parameters
HH: The HH of the end of the statement is the school checktology of the statement, and should be calculated to the GPS 25 board, the calculation rules are: 8 counts of all bytes after "S", each of the four forms a BCD code (A , B, C, etc. Application capitalization). GPS 25 outputs, there is a check bit after the statement, and the user can verify the results.
(2) Initialization information command (only on GPS 25)
$ PGRMI used to initialize the board to set the satellite position and time
This statement is usually used when the skirt position and the current actual location of more than 800 kilometers to memorize the positioning speed.
Format: $ PGRMI $ GPALM, <1>, <2>, <3>, <4>, <5>, <6>, * hh
<1> latitude ddmm.mmm format (initialization must be written to board)
<2> N or S in the latitude direction
<3> Longxue DDMM.MMM format (initialization must be written)
<4> longitude e or N
<5> Current UTC date, KKMM YY format
<6> Current UTC Time HHMM SS Format
(3) Board configuration information command (only for GPS 25)
$ GPALM Configure the parameters on the receiving board, stored on the standby battery.
$ GPALM, <1>, <2>, <3>, <4>, <5>, <9>, <10>, <11>, <12> * Hh
<1> Suitable Working Mode A - Auto, 2-2D Mode, 3-3D Mode
<2> Sea level height -1500.00 ~ 1800.00 meters <3> Geographic coordinate index
<4> User coordinates
<5> User's land coordinate precision
<6> User Land Coordinate X-axis
<7> User Coordinate Y-axis
<8> User Land Coordinate Z Axis
<9> Differential Mode A- Automatic (Automatic Output Difference Information when activation) D- Difference Mode
<10> NMEA baud rate 1 = 200 2 = 2400 3 = 4800 4 = 9600
<11> Speed Filter Status 0 = But filter 1- Auto 2 ~ 255 = filter time constant
<12> PPS mode: 1 = no z = 1 Hz
The changes of baud rates and PPS functions after reloading or PIN6 initialization.
(4) Activation of output statements (only for GPS 25)
$ PGRMO decides whether statement output.
$ PGRMO <1>, <2> * hh
(1) statement description
(2) Statement mode 0 - Close special 1 - Open Tote 2 - Close all 3 - Open All (Except GPALM)
Note: (1) If it is 2 or 3, do not test. Allows a segment
(2) If 0 or 1, the description field must be defined.
(3) If it does not work, if it does not work <1> <2> in the statement, the statement has no effect.
(4) $ PGRMO, GPALM, 1 will transfer all this lottery
2, NMEA send statement
Through the TXD pin (on the GPS 25 board)
(1) Transmission rate
User can be customizable
Transmission length table transmission length = total transmission total character / transmission number per second
Porter rate per second transmission number statement largest character 1200 120 GPGGA 72 2400 240 GPGSA 65 4800 480 GPGSV 210 9600 960 GPRMC 70
GPVTG 34
PGRME 36
PGRMT 47
PGRMV 26
PGRMF 79
LCGLL 36
LCDTG 34
The default baud rate is 48,000.
(2) Time transmission
Output UTC time and date, the current date time is obtained by the calculation board.
(3) The ephemeris of the global satellite (ALM)
$ GPALM, <1>, <2>, <3>, <4>, <5>, <9>, <10>, <11>, <12> , <13>, <14>, <15>, * HH
I can not be transmitted normally, you have to get it by initialization through $ PGRMO, GPALM, 1 command
* Between the data when reading the output statement, the data is used to distinguish, do not read it by bit to ensure application compatibility
(4) Location Information (GGA)
$ GPGGA, <1>, <5>, <6>, <7>, <8>, <9>, m, <11>, <12> * hh
<1> UTC Time, HH MM SS Format (positioning it)
<2> Longxue DD MM MMMM Format (Non 0) <3> Longxiang N or S
<4> latitude DDD MM MMMM format (non-0)
<5> Latitude E or W
<6> GPS Status Priority 0- Unmodified 1- None Differential Positioning Information 2 - Differential Location Information
<7> Use satellite number (00 ~ 08)
<8> Accuracy percentage
<9> Hay level height
<10> * Land with the height of the sea level
<11> Differential GPS Information
<12> Difference Station ID 0000-123
(5) GPS DOP and active satellite
$ GPGSA, <1>, <2>, <3>, <3>, <3>, <3>, <3>, <3>, <3> , <3>, <6>, * HH
<1> Mode M- manual, A-automatic
<2> Current Status 1 - No positioning information, 2-2d 3-3D
<3> PRN number 01 ~ 32
<4> Position Accuracy
<5> Vertical Accuracy
<6> Level Accuracy
(6) Current GPS Satellite Status (GSV)
$ GPGSV, <1>, <5>, <6>, <7> <4>, <5>, <6>, <7> * hh
<1> Total number of GSV statements
<2> Number of current GSV statements
<3> Show the total number of satellites 00 ~ 12
<4> Satellite's PRV
<5> Satellite elevation
<6> Satellite rotation corners
<7> Cycling
Two statements are two, and the first section consists of up to 4 stars. There are 4 data for each star, that is, <4> - asterisk <5> - elevation <6> - orientation <7>
(7) The simplest (RMC)
$ GPRMC, <1>, <2>, <6>, <7>, <8>, <9>, <10>, <11>, * hh < CR>
<1> UTC Time HHMMSS Format
<2> State A = Location V = Navigation
<3> DDMM.MMM format
<4> Operation direction n or s
<5> latitude dddmm.mmmm
<6> Latitude E or W
<7> rate
<8> Dismistency (pointing in two-dimensional direction, equivalent to two-dimensional container)
<9> Current UTC Date DDMMYY format
<10> Sun orientation
<11> Sun direction
(8) VTG speed relatively relatively northward direction
$ GPVTG, <1>, T, <2>, M, <3>, N, <4> K * HH
<1> True direction <2>, relative direction <3> Step <4>
(9) Geographic information command with Loran ID
LCGLL report location information $ lcgll, <1>, <2>, <3>, <4>, <5>
1, longitude, ddmm .mm format
2, longitude n or s
3, latitude, dddmm .mm format
4, latitude direction E or W
5, UTC time (positioning point) hHMMSS format
(10) Tracks, speed information with Loran ID
LCVTG Report Tracks and Speed Information
$ LCVTG, <1>, T, <2>, <3>, N, <4>, K,
1, true direction (relative to Zhengbei)
2, relative direction
3, step size
4, rate
(11) Evaluation error message
$ PGRME Report Evaluation Error Message
$ PGRME, <1>, M, <2>, M, <3>, M, * HH
1, GPS asterisk (0-1023)
2, additional PGS (0-604799)
3, UTC date (current point) hhmmss format
4, UTC time (current point) HHMMSS format
5, GPS jump second number
6, longitude, ddmm.mmmm format
7, longitude, n or s
8, latitude, DDDMM.MMMM format
9, latitude direction, e or w
10, mode M = manual a = automatic
11, positioning type 0 = no positioning 1 = 2D 2 = 3d
12, rate
13, azimuth
(13) Status information
$ PGRMT, <1>, <5>, <6>, <7>, <8>, <9> * hh
Report board status statement
1, product name, mode and software version
2, self-test P-through F- failed
3, receive detection P-through F- failed
4, store data status R-retain L-lost
5, clock data status R-save L-lost
6, crystal detection P- via F-test is incorrect
7. Data collection C-collection is not collected
8, plate temperature ° C
9, board configuration data R-retain L-lost
(14) 3D positioning information
$ PGRMV, <1>, <2>, <3> * hh
1. East Reality rate -999.9 to 9999.9
2, to the north real rate -999.9 to 9999.9
3, vertical rate -999.9 to 9999.9
$ Gpgsa, a, 1 ,,,,,,,,,,,, 99.9, 99.9, 99.9 * 09
$ Psny, 0,00, 05,500,06,06,06,06 * 14
$ GPVTG, 000.0, t, m, 000.0, n, 000.0, k * 60
$ GPGGA, 062320, 3537.8333, N, 13944.6667, E, 0, 00, 99.9, 0100, M,, M, 000,000 * 7D
$ GPGLL, 3537.8333, N, 13944.6667, E, 062320, V * 3B
$ GPRMC, 062320, V, 3537.8333, N, 13944.6667, E, 000.0 ,000.0, 030222, * 0D
$ GPZDA, 062320, 03, 02, 2022 ,, * 4E
$ GPGSV, 1,1,00 ,,,,,,,,,,,,,, * 79
$ GPVTG, 000.0, t, m, 000.0, n, 000.0, k * 60
$ GPGGA, 062321, 3537.8333, N, 13944.6667, E, 0, 00, 99.9, 0100, M,, M, 0000 * 7C $ GPGLL, 3537.8333, N, 13944.6667, E, 062321, V * 3A
$ GPRMC, 062321, V, 3537.8333, N, 13944.6667, E, 000.0 ,000.0, 030222,, * 0C
$ GPZDA, 062321, 03, 02, 2022 ,, * 4F
$ Gpgsa, a, 1 ,,,,,,,,,,,, 99.9, 99.9, 99.9 * 09
$ Psny, 0,00, 05,500,06,06,06,06 * 14
$ GPVTG, 000.0, t, m, 000.0, n, 000.0, k * 60
$ GPGGA, 062322, 3537.8333, N, 13944.6667, E, 0, 00, 99.9, 0100, M,, M, 000,000 * 7F
$ GPGLL, 3537.8333, N, 13944.6667, E, 062322, V * 39
$ GPRMC, 062322, V, 3537.8333, N, 13944.6667, E, 000.0 ,000.0, 030222, * 0F
$ GPZDA, 062322, 03, 02, 2022,, * 4C
