Table of Contents
Advertisement
5. Software Specification
5.1 EB-N701 NMEA Protocol
The EB-N701 software is capable of supporting the following NMEA message formats
NMEA Message
Prefix
$GPGGA(1)*
$GPGLL
$GPGSA(3)*
$GPGSV(3)*
$GPRMC(1)*
$GPVTG(1)*
$GPZDA
*:
(1): 1sec output 1msg , (3): 3sec output 1msg , 9600 baud rate (Standard output)
5.2 General NMEA Format
The general NMEA format consists of an ASCII string commencing with a '$' character and
terminating with a <CR><LF> sequence. NMEA standard messages commence with 'GP' then a
3-letter message identifier. The message header is followed by a comma delimited list of fields
optionally terminated with a checksum consisting of an asterix '*' and a 2 digit hex value representing
the checksum. There is no comma preceding the checksum field. When present, the checksum is
calculated as a bitwise exclusive of the characters between the '$' and '*'. As an ASCII representation,
the number of digits in each number will vary depending on the number and precision, hence the
record length will vary. Certain fields may be omitted if they are not used, in which case the field
position is reserved using commas to ensure correct interpretation of subsequent fields.
The tables below indicate the maximum and minimum widths of the fields to allow for buffer size
allocation.
EverMore Technology Inc.
2F, No.7, R&D Road 1, Science-Based Industrial Park, Hsinchu, Taiwan, 300, R.O.C.
Format
GPS fix data.
Geographic position Latitude / Longitude.
GNSS DOP and actives satellites
Satellites in view.
Recommended minimum specific GNSS data.
Velocity and track over ground.
Date and time.
EB-N701 User's Manual
18
Direction
Out
Out
Out
Out
Out
Out
Out
http://www.emt.com.tw
Advertisement
Table of Contents
