GPS - Réception trames NMEA étranges sur HTC Polaris

Bonjour,

Je suis en train de faire un petit programme pour afficher les coordonnées GPS ainsi que le cap sur mon PDA. Je rencontre un petit "problème" lors de la récupération des trames :
Au lancement j'ai quelques lignes de $GPGSV puis $GPGGA, $GPRMC, $GPGSA, $GPVTG, jusque là tout va bien. Mais par moment je ne vois arriver que les trames $GPGSV pendant x secondes (il y a même des lignes qui ressemblent à des $GPGSV dont le début est enlevé...) puis ensuite ça redevient normal et quelques temps plus tard ça recommence à déc..ner
Je n'observe pas ce phénomène de perte de position quand je suis sous tomtom donc je ne pense pas que c'est dû à la puce mais peut-être à la façon de lire sur le port série...
Quelqu'un a-t-il déjà rencontré ce problème ?

Voici un extrait de ce que je lit sur le port série pendant quelques minutes (étant à l'intérieur devant mon PC, pas de fix obtenu pendant cet essai, mais le problème est le même quand j'ai le fix) :


$GPGSV,3,1,09,01,43,068,,11,84,195,,14,29,047,,17,23,312,*71
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,,11,84,195,20,14,29,047,,17,23,312,*73
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,,11,84,195,18,14,29,047,,17,23,312,*78
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,,11,84,195,18,14,29,047,,17,23,312,*78
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
17,23,312,*78
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
3,312,*71
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
2,*71
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
1
$GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
GPGSV,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
V,3,2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
2,09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
09,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,19,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
9,22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
22,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,163,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
63,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,,20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
20,54,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
4,240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
0,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
3,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,16,28,17,272,*7E
$GPGSV,3,3,09,32,82,219,*41
,16,28,17,272,*7E
$GPGSV,3,3,09,32,82,219,*41
,18,28,17,272,*70
$GPGSV,3,3,09,32,82,219,*41
,18,28,17,272,*70
$GPGSV,3,3,09,32,82,219,*41
,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
7,272,*79
$GPGSV,3,3,09,32,82,219,*41
7,272,*79
$GPGSV,3,3,09,32,82,219,*41
7,272,*79
$GPGSV,3,3,09,32,82,219,*41
7,272,*79
$GPGSV,3,3,09,32,82,219,*41
272,*79
$GPGSV,3,3,09,32,82,219,*41
2,*79
$GPGSV,3,3,09,32,82,219,*41
*79
$GPGSV,3,3,09,32,82,219,*41
9
$GPGSV,3,3,09,32,82,219,*41
$GPGSV,3,3,09,32,82,219,*41
GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPGSV,3,3,09,32,82,219,*41
9
$GPGSV,3,3,09,32,82,219,*41
*79
$GPGSV,3,3,09,32,82,219,*41
2,*79
$GPGSV,3,3,09,32,82,219,*41
7,272,*7C
$GPGSV,3,3,09,32,82,219,*41
,17,272,19*74
$GPGSV,3,3,09,32,82,219,*41
,,28,17,272,19*74
$GPGSV,3,3,09,32,82,219,*41
,185,,28,17,272,19*74
$GPGSV,3,3,09,32,82,219,*41
07,185,,28,17,272,19*74
$GPGSV,3,3,09,32,82,219,*41
3,07,185,,28,17,272,19*74
$GPGSV,3,3,09,32,82,219,*41
0,,23,07,185,,28,17,272,*7C
$GPGSV,3,3,09,32,82,219,*41
240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
240,,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
,23,07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
07,185,,28,17,272,*79
$GPGSV,3,3,09,32,82,219,*41
85,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,17*4F
85,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,21*4A
,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,21*4A
09,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,21*4A
09,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,21*4A
09,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,18*40
,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,18*40
,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,18*40
,185,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
85,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,,28,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
28,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
,16,271,*74
$GPGSV,3,3,09,32,84,217,*49
6,271,*74
$GPGSV,3,3,09,32,84,217,*49
1,*74
$GPGSV,3,3,09,32,84,217,*49
$GPGSV,3,3,09,32,84,217,*49
V,3,3,09,32,84,217,*49
$GPGGA,,,,,,0,,,,,,,,*66
,32,84,217,*49
$GPGGA,,,,,,0,,,,,,,,*66
,217,*49
$GPGGA,,,,,,0,,,,,,,,*66
,*49
$GPGGA,,,,,,0,,,,,,,,*66
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
,,,*66
$GPRMC,,V,,,,,,,,,,N*53
PRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
*53
GSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
,272,*75
$GPGSV,3,3,09,32,82,219,*41
PGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
2,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,32,11,84,201,,14,28,047,,17,24,312,*78
$GPGSV,3,2,09,19,21,163,,20,55,240,,23,08,185,,28,16,272,*75
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,32,11,84,201,,14,28,047,,17,24,312,*78
$GPGSV,3,2,09,19,21,163,,20,55,240,,23,08,185,,28,16,272,*75
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,32,11,84,201,,14,28,047,,17,24,312,*78
$GPGSV,3,2,09,19,21,163,,20,55,240,,23,08,185,,28,16,272,*75
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,32,11,84,201,,14,28,047,,17,24,312,*78
$GPGSV,3,2,09,19,21,163,,20,55,240,,23,08,185,,28,16,272,23*74
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E
$GPGSV,3,1,09,01,43,068,32,11,84,201,,14,28,047,,17,24,312,*78
$GPGSV,3,2,09,19,21,163,,20,55,240,,23,08,185,,28,16,272,23*74
$GPGSV,3,3,09,32,82,219,*41
$GPGGA,,,,,,0,,,,,,,,*66
$GPRMC,,V,,,,,,,,,,N*53
$GPGSA,A,1,,,,,,,,,,,,,,,,*32
$GPVTG,,T,,M,,N,,K*4E

Merci.

je serais tenter de te dire de changer la vitesse de lecture, visiblement tu ne lis pas assez ou top vite les trames se referer aux caractéristiques de ton gps

Le savoir n'est que le filtre de l'experience

Bonjour,

merci de ta réponse, j'ai essayé à 4800 bauds et à 9600 bauds dans les propriétés de l'objet PortSérie (le gps) et j'ai le même soucis...