Magellan GPS 315 User Manual - Page 64

GSA GPS DOP and Active Satellites GPS receiver operating mode, satelites used in the navigation solution reported by the $--GGA sentence, and DOP values. 1 2 3 45 67 GSA,a,x,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,x.x,x.x,x.x*hh, 1 Mode: M=Manual, forced to operate in 2D or 3D mode, A=Automatic, allowed to automatically switch 2D/3D 2 Mode: 1= Fix not available, 2=2D, 3=3D 3-4 PRN numbers of satellites used in solution (null for unused fields) 5 PDOP 6 HDOP 7 VDOP GSV GPS Satellites in View Number of satellites (SV) in view, PRN numbers, elevation, azimuth and SNR value. Four satellites maximum per transmission, additional satellite data sent in second or their message. Total number of messages being transmitted and the number of messages being transmitted is indicated in the first two fields. 123 4 5 6 78 9 10 11 GSV,x,x,xx,xx,xx,xxx,xx.........,xx,xx,xxx,xx*hh 1 Total number of messages, 1 to 9 2 Message number, 1 to 9 3 Total numer of satellites in view 4 Satellite PRN number 5 Elevation, degrees, 90° maximum 6 Azimuth, degrees True, 000 to 359 7 SNR (C/No) 00-99 dB, null when not tracking 8-9 2nd-3rd SV 10-11 4th SV Notes: 1) Satellite information may require the transmission of multiple messages. The first field specifies the total number of messages, minimum value 1. The second field identifies the order of this message (message number), minimum value 1. 2) A variable number of "PRN-Elevation-Azimuth-SNR" sets are allowed up to a maximum of four sets per message. Null fields are not required for unused sets when less than four sets are transmitted. 56 Magellan GPS 315/GPS 320