// https://forum.arduino.cc/t/dtostrf-output-not-as-expected/167966
  
  float lon = 34.123456;
  float lat = -138.654321;

  char lonBuffer[20];
  char latBuffer[20];

 
void setup() {

  dtostrf(lon,9, 6, lonBuffer);//(float,lengthIncDecimalPt,intsAfterDecimalPt,array)
  dtostrf(lat,11, 6, latBuffer);
 
  Serial.begin(9600);

  Serial.print("LON: ");
  Serial.println(lonBuffer);
  Serial.print("LAT: ");
  Serial.println(latBuffer);
  Serial.println();
  
 
}
 
void loop(){ 

}