Garmin GPS 16x - Manual (Page 18)

190-00228-08 GPS 16x Technical Specifications Rev. B
Page 14
4.2 TRANSMITTED NMEA 0183 SENTENCES
The subsequent paragraphs define the sentences that can be transmitted on COM1 by the GPS sensor.
4.2.1 Sentence Transmission Rate
Sentences are transmitted with respect to the user selected baud rate.
The GPS sensor will transmit each sentence (except where noted in particular transmitted sentence descriptions) at a
periodic rate based on the user selected baud rate and user selected output sentences. The GPS sensor will transmit
the selected sentences contiguously. The length of the transmission can be determined by the following equation and
Tables 2 and 3:
total characters to be transmitted
length of transmission = ---------------------------------------------
characters transmitted per second
Sentence Output by Default? Maximum Characters
GPRMC 74
GPGGA 82
GPGSA 66
GPGSV 70
PGRME 35
GPGLL 44
GPVTG 42
PGRMV 32
PGRMF 82
PGRMB 40
PGRMM 32
PGRMT 50
Table 2: NMEA 0183 Output Sentence Order and Size
Baud Characters per Second
4800 480
9600 960
19200 1920
38400 3840
Table 3: Characters per Second for Available Baud Rates
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 . The factory set
defaults will result in a once-per-second transmission at the NMEA 0183 specification transmission rate of 4800
baud.
Regardless of the selected baud rate, the information transmitted by the GPS sensor is referenced to the one-pulse-
per-second output pulse immediately preceding the GPRMC sentence, or whichever sentence is output first in the
burst (see Table 2 above).