Garmin GPS 20x, Технические характеристики

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190-00880-00 GPS 20x Technical Specifications Rev. A
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3 GPS 20x SOFTWARE INTERFACE
The GPS 20x transmits using the Garmin USB interface. The Garmin USB interface is discussed in the Garmin
Device Interface Specification found in the Garmin Device Interface SDK located on the Garmin Web site at:
www.garmin.com/support/commProtocol.html.
You can configure the GPS 20x to transmit binary data information over the USB interface. Refer to Appendix B:
Garmin Binary Output Format .
3.1 TRANSMITTED NMEA 0183 SENTENCES
The following paragraphs define the sentences that can be transmitted by the GPS 20x using Spanner (an application
that can provide NMEA output via a virtual COM port). Spanner is available for free on the Garmin web site. To
download the software, start at
www.garmin.com/oem , select the GPS 20x, and then select Updates & Downloads .
3.1.1 Sentence Transmission Rate
Sentences are transmitted with respect to the user selected baud rate.
The GPS sensor will transmit each sentence once per second. The sentences are not configurable.
Sentence Maximum Characters
GPRMC 74
GPGGA 82
GPGSA 66
GPGSV 70
PGRMT 50
Table 1: NMEA 0183 Output Sentence Order and Size
The maximum number of fields allowed in a single sentence is 82 characters including delimiters. Values in the
table include the sentence start delimiter character “$” and the termination delimiter <CR><LF>.