GP-20U7 With Arduino

Does anyone know how to use the GPS unit GP-20U7 with Arduino? It is a fairly standard GPS, and I should be able to easily communicate with it. The problem is that it comes with the RX port covered up. The wires that come soldered onto it are only connected to the power, ground, and TX port. Anyone have any ideas?

Thank you!

kornexls:
Does anyone know how to use the GPS unit GP-20U7 with Arduino? It is a fairly standard GPS, and I should be able to easily communicate with it. The problem is that it comes with the RX port covered up. The wires that come soldered onto it are only connected to the power, ground, and TX port. Anyone have any ideas?

Thank you!

I just ordered one, so I hope I can figure it out!

What would you do with the RX input?
Have you found any information on programming the module?

I found this library for it. Still not clear on how to use it without 2 way serial. I should have it next week, so I can experiment then.

All that "library" does is read GPGGA sentences from TX.

jremington:
All that "library" does is read GPGGA sentences from TX.

Thanks for the review. :slight_smile: I hadn't even downloaded that library - until I have the component and some time, I'm gonna keep it on the back burner. I've built devices with Adafruit's Ultimate GPS module, and it was pretty easy. I expect this one will be a bit more challenging, as Adafruit holds your hand while leading you through the garden of electronic delights.

But it was $30 cheaper!

Any news on this implementation ?

I just connected Vcc to 3.3V, GND to Ground and TX to RX on arduino UNO and the Serial Monitor starts to pop up the chars from NMEA messages.

More: GitHub - sidwarkd/gp20u7_arduino: A simple Arduino library for the GP20U7 GPS unit

Vcc pin from GP-20U7 to 3.3V
GND to GND
TX from GP-20U7 to PIN10

// GPS Module - GP-20U7 - Arduino UNO Example
//
// Author: Gustavo Bertoli
//
// References:
// https://cdn.sparkfun.com/datasheets/GPS/GP-20U7.pdf
// https://www.arduino.cc/en/Reference/SoftwareSerial
// http://forum.arduino.cc/index.php?topic=288234.0
// 

#include <SoftwareSerial.h> 

SoftwareSerial GPS_Serial(10, 11); // RX, TX

void setup() {
  Serial.begin(9600);
  GPS_Serial.begin(9600); 
}

void loop() {
   char rc;

   if (GPS_Serial.available()){
        rc = GPS_Serial.read();
        Serial.write(rc);
   }
}

Here's why there is no connections TO the device: It doesn't need any. It is "dumb". It can't accept any commands. Give it power- it starts sending a stream of ASCII (9600 baud serial, 3v3). At first, there's a datum in the NMEA sentences saying "this data is meaningless".

If it has a good view of the sky, and is operating up to spec, within 30 seconds, that code will change, to say "the data is now valid, meaningful."

It is a GREAT device! (And inexpensive... about US$18) If I'd known then what I know now, I would have had it up and running in very short order. The Sparkfun "support" (at 23 Aug 20) is worse than useless... very much an exception to the rule... it sent me off down several irrelevant blind alleys.

I've written up using one of these with an Arduino...

https://wywtk.com/ec/iec/iec217.htm

Comments by email welcome. Re-posts, "Like"s, mentions elsewhere VERY welcome. It was a lot of work to write up, even though the device is EASY to use. That work is wasted if no one hears about it.

Remember: If you hang one of these on a project... costs two digital pins (one goes to waste, but has to be set up to keep SoftwareSerial happy), if you hang one... you can "throw away" the location data, and "just" use the unit for an accurate date/time!

Thanks for the tip.