Twan Dieltjes

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9 years, 4 months ago.

garmin 64 st in NMEA mode connect to a nucleo?

I have a garmin 64st device which should be able to output it's gps information via NMEA / usb. Does anyone know if it is possible to connect this to the nucleo f411re?

My idea is to build a trip computer for hobby rally sports. It should calculate distance between GPS coordinates and display it on a 7 seg display because they are readable in the dark.

If not, maybe I have to buy an external GPS device like the adafruit Ultimate

2 Answers

Wim Huiskamp
9 years, 4 months ago.

I dont know that specific Garmin, but if it outputs NMEA strings on a serial port it should be possible to read that on any mbed platform with a serial port. Just make sure you have a common ground and connect the TX output of the GPS to the RX input on mbed, make sure the voltage level is correct (RS232 levels are NOT suitable, needs to be converted to 3V3 using a MAX3232 or similar). Make sure the baud rate is set correctly. You could first test the Garmin on a PC terminal window to figure out which NMEA messages it spits out (RMC etc).

The GPS component libs should be good starting point for your code. https://developer.mbed.org/components/cat/gps/

Kamil M
9 years, 4 months ago.

Hello,

It is possible to get NMEA sentences via USB. Moreover, it is really easy to catch and parse the sentence via Rx... The only difficulty (little bit) is setting the GPS module with correct interval and how your ARM side will act if no satellite tracked or catched by GPS. In that case you will get few ,, from Rx :)

If your aim is specific, i mean, lets say, if you only want to lat, long, and altititude data, you even don't need any library. Just collect bytes from Rx to an char array or to string and analyze.

Standart NMEA sentence, which is RMC I think as Wim said, contains enough information. You also can try the sentence GPGAA i think... I did prefer it before to RMC in ublox and Telit....

Regards.