I found the solution from a French Forum, Anyway, thank you very much for your help. I will remember you and tell about your great forum. I learned à lot
The solution was: gtkterm to change the configuration of ttyS0, it was on 9600 baud, and in the "help" from openCPN
to put the gps on NMEA
6 days (several hours per days) of research
, and one white night !!!
And it works now
Thank you again