: All standard sentences start with a $ character and end with a carriage return/line feed .
Because marine environments are electrically noisy, data corruption is possible. The checksum is a vital fail-safe. nmea 0183 sentences pdf
NMEA data is streamed as lines of text. Each distinct line is called a "sentence." Every sentence begins with a dollar sign ( $ ) and ends with a carriage return and line feed ( <CR><LF> ). : All standard sentences start with a $