2Software Interface
2.1 NMEA V3.0 Protocol
Its output signal level is TTL: 4800 bps (default), 8 bit data, 1 stop bit and no parity. It supports the following
Messages: GGA, GLL, GSA, GSV, RMC and VTG.
NMEA Output Messages: the Engine board outputs the following messages as shown in Table
Table 2-1 NMEA-0183 Output Messages
NMEA Record | Description |
|
|
GGA | Global positioning system fixed data |
|
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GLL | Geographic position – latitude / longitude |
|
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GSA | GNSS DOP and active satellites |
|
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GSV | GNSS satellites in view |
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RMC | Recommended minimum specific GNSS data |
|
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VTG | Course over ground and ground speed |
|
|
2.1.1 GGA-Global Positioning System Fixed Data
Table
$GPGGA, 161229.487, 3723.2475, N, 12158.3416, W, 1, 07, 1.0, 9.0, M, , , ,0000*18
Table 2-2 GGA Data Format
Name | Example | Units | Description |
|
|
|
|
Message ID | $GPGGA |
| GGA protocol header |
|
|
|
|
UTC Position | 161229.487 |
| hhmmss.sss |
|
|
|
|
Latitude | 3723.2475 |
| ddmm.mmmm |
|
|
|
|
N/S Indicator | N |
| N=north or S=south |
|
|
|
|
Longitude | 12158.3416 |
| Dddmm.mmmm |
|
|
|
|
E/W Indicator | W |
| E=east or W=west |
|
|
|
|
Position Fix Indicator | 1 |
| See Table |
|
|
|
|
Satellites Used | 07 |
| Range 0 to 12 |
|
|
|
|
HDOP | 1.0 |
| Horizontal Dilution of Precision |
|
|
|
|
MSL Altitude | 9.0 | meters |
|
|
|
|
|
Units | M | meters |
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|
|
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12
