Thanks guys! I will probably be able to sell this piece of kit eventually. Depends on interest.
Today I got my first NMEA log! Wonderful feeling... (below)
It will take a bit longer to try out the gyro circuitry. I also want to write the code for interpreting BMW IBus speed messages and simulate tacho pulses before I am done with this design. So with an E46 you will not have to connect tacho and direction signals. You can do if you've got another car.
Plan is to be done in June.
BMW OEM GPS Antenna (part numbers are visible)
GPS in box.
Edit:
I've now got valid GPS data so I know that my antenna is working!¨
$GPVTG,000.0,T,,M,000.0,N,000.0,K,A*0D
$GPRMC,132321.93,A,5921.39125,N,01758.66222,E,000. 0,000.0,230408,,,A*53
$GPGSA,A,3,27,08,04,07,02,25,,,,,,,5.05,3.47,3.68* 04
$GPGSV,3,1,12,27,40,188,39,10,14,300,,13,85,142,,0 2,40,277,32*78
$GPGSV,3,2,12,20,11,133,,29,12,348,,23,,000,,08,10 ,198,34*70
$GPGSV,3,3,12,16,25,060,,04,37,230,41,25,61,154,32 ,07,43,178,40*73
$GPGGA,132322.93,5921.39122,N,01758.66224,E,1,06,3 .47,00024.4,M,023.4,M,,*6F
Btw. Is someone using time data to set time in car?