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dragino / TrackerD

For Dragino TrackerD, which support GPS+WiFi+BLE+TEMP+HUM+ motion
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Communicating with the L70 GPS module #29

Open athanas opened 3 months ago

athanas commented 3 months ago

The code uses the SerialGPS device in GPS.cpp to retrieve NMEA data from the L70 module. I have an application where I'd like to use the AllwaysLocate capabilities of the L70 (see Section 3.4.5 of https://docs.rs-online.com/74ea/0900766b8147dbe2.pdf). To do so, I need to send the NMEA command $PMTK255,8*23 to the L70. The problem is that no matter what command that I send to the L70, it seems to be ignored. For example,

if SerialGPS.availableForWrite() >20) {
   // The code reaches this point with plenty of write buffer space
   SerialGPS.write("$PMTK255,8*23\r\n");
}

This should provide a NMEA response of $PMTK001,225,3*33. In fact, I see no effect or response from any command that I issue.

The PCB layout shows the RX/TX lines properly connected between the L70 and the ESP32. Any idea why this is not working?

namejinnameyuan commented 3 months ago

Our TrackerD currently uses the GPS model L76K, which does not have this command