SENSORS/ACTUATORS

INTERNET OF THING (IoT)

ESP32 S3 UNO - GPS

This ESP32 S3 Uno GPS tutorial shows you how to connect a NEO-6M GPS module to the ESP32 S3 Uno form board and read your location with Arduino code. You will get the GPS coordinates (latitude, longitude and altitude), the speed in km/h, and the current date and time. You will also learn how to measure the distance from where you are to a fixed place, such as London.

In this tutorial, you will:

Learn the pinout of the NEO-6M GPS module.
Wire the GPS module to the ESP32 S3 Uno using a hardware serial port.
Install the TinyGPSPlus library in the Arduino IDE.
Read GPS coordinates, speed, date and time on the Serial Monitor.
Calculate the distance between two GPS locations.

Hardware Preparation

1	×	ESP32 S3 Uno-form Board
1	×	USB Cable Type-A to Type-C (for USB-A PC)
1	×	USB Cable Type-C to Type-C (for USB-C PC)
1	×	NEO-6M GPS module
1	×	Jumper Wires

Or you can buy the following kits:

DIYables Sensor Kit (18 sensors/displays)

Disclosure: Some of the links provided in this section are Amazon affiliate links. We may receive a commission for any purchases made through these links at no additional cost to you.
Additionally, some of these links are for products from our own brand, DIYables .

Overview of NEO-6M GPS module

The NEO-6M is a small, low-cost GPS receiver. It listens to satellites and sends your position and time as plain text (NMEA sentences) over a serial line. A library turns that text into numbers you can use, so your code stays short.

The module needs a clear view of the sky to get a fix. Indoors, it may take many minutes or never find the satellites at all.

Pinout

The NEO-6M GPS module has only four pins, so the wiring is quick. Two pins give power and two pins carry the serial data.

VCC pin

Connect this pin to the power supply. Most NEO-6M boards have their own regulator, so you can feed them 5V (or 3.3V on many modules).

GND pin

Connect this pin to GND (0V).

TX pin

The module sends GPS data out on this pin. Connect it to an RX pin of the ESP32 S3 Uno.

RX pin

The module receives commands on this pin. Connect it to a TX pin of the ESP32 S3 Uno.

ESP32 S3 Uno Pinout

The image below shows the pinout of the ESP32 S3 Uno form board. Use it to find the Uno header pins (D3, D4…) and their GPIO numbers while you wire the GPS module.

Wiring Diagram

The GPS module talks to the board through a serial line, so its TX goes to the board's RX and its RX goes to the board's TX. The ESP32 S3 Uno can put a hardware UART on almost any pin, so D4 and D3 work well here.

This image is created using Fritzing. Click to enlarge image

GPS Module Pin	ESP32 S3 Uno Pin
VCC	5V
GND	GND
TX	D4 (GPIO19)
RX	D3 (GPIO17)

ESP32 S3 Uno Code

Many GPS examples use SoftwareSerial, but that library does not exist on the ESP32 S3 Uno. Instead, the code uses the built-in hardware serial port UART1 and maps it to GPIO19 (RX) and GPIO17 (TX). This is more reliable than a software serial port.

Reading GPS coordinates, speed (km/h), and date time

This sketch reads the text from the GPS module and feeds it to TinyGPSPlus one character at a time. Each time a full sentence arrives, it prints the latitude, longitude, altitude, speed, date and time. If no data comes in after 5 seconds, it prints a message that tells you to check the wiring.

/* * This ESP32 S3 Uno code was developed by newbiely.com * * This ESP32 S3 Uno code is made available for public use without any restriction * * For comprehensive instructions and wiring diagrams, please visit: * https://newbiely.com/tutorials/esp32-s3-uno/esp32-s3-uno-gps */ #include <TinyGPS++.h> #define RX_PIN 19 // The ESP32 S3 Uno pin connected to the TX of the GPS module (D4) #define TX_PIN 17 // The ESP32 S3 Uno pin connected to the RX of the GPS module (D3) TinyGPSPlus gps; // the TinyGPS++ object HardwareSerial gpsSerial(1); // the hardware serial interface (UART1) to the GPS module void setup() { Serial.begin(9600); gpsSerial.begin(9600, SERIAL_8N1, RX_PIN, TX_PIN); // Default baud of NEO-6M GPS module is 9600 Serial.println(F("ESP32 S3 Uno - GPS module")); } void loop() { if (gpsSerial.available() > 0) { if (gps.encode(gpsSerial.read())) { if (gps.location.isValid()) { Serial.print(F("- latitude: ")); Serial.println(gps.location.lat()); Serial.print(F("- longitude: ")); Serial.println(gps.location.lng()); Serial.print(F("- altitude: ")); if (gps.altitude.isValid()) Serial.println(gps.altitude.meters()); else Serial.println(F("INVALID")); } else { Serial.println(F("- location: INVALID")); } Serial.print(F("- speed: ")); if (gps.speed.isValid()) { Serial.print(gps.speed.kmph()); Serial.println(F(" km/h")); } else { Serial.println(F("INVALID")); } Serial.print(F("- GPS date&time: ")); if (gps.date.isValid() && gps.time.isValid()) { Serial.print(gps.date.year()); Serial.print(F("-")); Serial.print(gps.date.month()); Serial.print(F("-")); Serial.print(gps.date.day()); Serial.print(F(" ")); Serial.print(gps.time.hour()); Serial.print(F(":")); Serial.print(gps.time.minute()); Serial.print(F(":")); Serial.println(gps.time.second()); } else { Serial.println(F("INVALID")); } Serial.println(); } } if (millis() > 5000 && gps.charsProcessed() < 10) Serial.println(F("No GPS data received: check wiring")); }

Detailed Instructions

Follow these steps in order:

New to the ESP32 S3 Uno? Follow ESP32 S3 Uno - Getting Started first.
Wire it up as shown in the diagram.
Connect the board to your computer with a USB Type-C cable.
Open Arduino IDE, choose the ESP32S3 Dev Module board and the correct COM port.
Open the Library Manager by clicking the Libraries icon on the left side of the Arduino IDE.
Search for the library: type TinyGPSPlus in the search box and find TinyGPSPlus by Mikal Hart.
Install it by clicking the Install button.

Search for TinyGPSPlus created by Mikal Hart and click the Install button.

Newbiely | Arduino IDE 2.3.8

──

☐

Library Manager

TinyGPSPlus

All

TinyGPSPlus by Mikal Hart

NMEA is the standard format GPS devices use to report location, time, altitude, etc. TinyGPSPlus is a compact, resilient library that parses the most common NMEA 'sentences' used: GGA and RMC. It can also be customized to extract data from *any* compliant sentence. More info

1.0.3

INSTALL

Newbiely.ino

···

1 void setup() {

Output

Serial Monitor

Ln 1, Col 1

ESP32S3 Dev Module on COM15

Copy the code above and paste it into the Arduino IDE.
Upload the code by clicking the Upload button.
Place the GPS antenna near a window or outside, then open the Serial Monitor at 9600 baud.
Tip: the first fix after power-up (cold start) can take a few minutes. Until then, you will see INVALID values.

Newbiely | Arduino IDE 2.3.8

──

☐

Newbiely.ino

···

8 Serial.println("Hello World!");

Output

Serial Monitor

Message (Enter to send message to 'ESP32S3 Dev Module' on 'COM15')

New Line

9600 baud

ESP32 S3 Uno - GPS module - latitude: 21.03 - longitude: 105.85 - altitude: 18.40 - speed: 0.35 km/h - GPS date&time: 2026-10-2 8:15:42

Ln 11, Col 1

ESP32S3 Dev Module on COM15

Calculating the distance from current location to a predefined location

This sketch works out how far you are from London (latitude: 51.508131, longitude: -0.128002). It uses the distanceBetween() function of TinyGPSPlus, which returns meters, and divides the result by 1000 to show kilometers.

/* * This ESP32 S3 Uno code was developed by newbiely.com * * This ESP32 S3 Uno code is made available for public use without any restriction * * For comprehensive instructions and wiring diagrams, please visit: * https://newbiely.com/tutorials/esp32-s3-uno/esp32-s3-uno-gps */ #include <TinyGPS++.h> #define RX_PIN 19 // The ESP32 S3 Uno pin connected to the TX of the GPS module (D4) #define TX_PIN 17 // The ESP32 S3 Uno pin connected to the RX of the GPS module (D3) TinyGPSPlus gps; // the TinyGPS++ object HardwareSerial gpsSerial(1); // the hardware serial interface (UART1) to the GPS module const double LONDON_LAT = 51.508131; const double LONDON_LON = -0.128002; void setup() { Serial.begin(9600); gpsSerial.begin(9600, SERIAL_8N1, RX_PIN, TX_PIN); // Default baud of NEO-6M GPS module is 9600 Serial.println(F("ESP32 S3 Uno - GPS module")); } void loop() { if (gpsSerial.available() > 0) { if (gps.encode(gpsSerial.read())) { if (gps.location.isValid()) { double latitude = gps.location.lat(); double longitude = gps.location.lng(); unsigned long distanceKm = TinyGPSPlus::distanceBetween(latitude, longitude, LONDON_LAT, LONDON_LON) / 1000; Serial.print(F("- latitude: ")); Serial.println(latitude); Serial.print(F("- longitude: ")); Serial.println(longitude); Serial.print(F("- distance to London: ")); Serial.println(distanceKm); } else { Serial.println(F("- location: INVALID")); } Serial.println(); } } if (millis() > 5000 && gps.charsProcessed() < 10) Serial.println(F("No GPS data received: check wiring")); }

Detailed Instructions

Copy the code above and paste it into the Arduino IDE.
Upload the code to the ESP32 S3 Uno by clicking the Upload button.
Open the Serial Monitor at 9600 baud and look at the result.
Tip: change LONDON_LAT and LONDON_LON to the coordinates of your home or school to measure the distance to that place.

Newbiely | Arduino IDE 2.3.8

──

☐

Newbiely.ino

···

8 Serial.println("Hello World!");

Output

Serial Monitor

Message (Enter to send message to 'ESP32S3 Dev Module' on 'COM15')

New Line

9600 baud

ESP32 S3 Uno - GPS module - latitude: 21.03 - longitude: 105.85 - distance to London: 9246

Ln 11, Col 1

ESP32S3 Dev Module on COM15

Video Tutorial

Watch the video below to see this ESP32 S3 Uno project step by step.

FAQ

Can I use SoftwareSerial with the ESP32 S3 Uno?

No. The SoftwareSerial library from the UNO R4 does not work on the ESP32 S3 Uno. Use a hardware serial port instead, such as HardwareSerial(1) with gpsSerial.begin(9600, SERIAL_8N1, RX_PIN, TX_PIN). You can choose the RX and TX GPIOs yourself.

Why does the Serial Monitor show INVALID for the location?

The GPS module has not found enough satellites yet. Take it outside or put it next to a window, and wait a few minutes. When the small LED on the module starts to blink, it has a fix.

Why do I see only two decimals in the latitude and longitude?

Serial.println() prints a double with two decimals by default. Use Serial.println(gps.location.lat(), 6) to print six decimals, which gives a position accurate to about 10 cm in the number (the real GPS accuracy is a few meters).

Is the GPS time my local time?

No. The GPS module gives UTC time. Add or subtract your time zone offset in the code to get your local time.

What if my project needs more pins than the Uno headers give?

The ESP32 S3 Uno has two extra rows of holes with more GPIOs: GPIO15 and GPIO16 (I/O, PWM, analog), GPIO45 and GPIO35 to GPIO42 (I/O, PWM), and GPIO47/GPIO48 (output only, PWM). Solder pin headers to use them and write the GPIO number in code. For a GPS project, GPIO35 to GPIO42 are good for extra serial devices or buttons, and GPIO15/16 fit analog sensors. Do not use GPIO47/GPIO48 for inputs. Be careful with two things. First, GPIO47/GPIO48 may run at 1.8V instead of 3.3V on some modules (especially ones with "V" in the name, like R8V or R16V), so 3.3V devices can be damaged or act strangely. Second, GPIO0, GPIO3 (D6), GPIO45 and GPIO46 (D9) are boot strapping pins, and a wrong connection can stop the board from booting or uploading code. Use the other extra pins first.

Troubleshooting

Problem	Possible Cause	Solution
No COM port in the Arduino IDE	USB driver missing or charge-only cable	Install the CP210x or CH340 driver, use a data USB cable, or hold BOOT while you press RESET
"No GPS data received - check wiring" message	TX and RX are swapped or a wire is loose	Connect GPS TX to D4 (GPIO19) and GPS RX to D3 (GPIO17), and check VCC and GND
Location stays INVALID for a long time	No clear view of the sky	Move the module outside or near a window and wait a few minutes for the first fix
Strange characters instead of GPS data	Wrong baud rate	Keep gpsSerial at 9600 and set the Serial Monitor to 9600 baud
Compile error about TinyGPS++.h	Library not installed	Install TinyGPSPlus by Mikal Hart from the Library Manager
Compile error about SoftwareSerial.h	Using code made for other boards	Use the ESP32 S3 Uno code above, which uses HardwareSerial
Board resets or GPS LED is off	Weak power supply	Power the module from the 5V pin and use a good USB cable

Learn More

※ OUR MESSAGES

As freelancers, We are AVAILABLE for HIRE. See how to outsource your project to us
Please feel free to share the link of this tutorial. However, Please do not use our content on any other websites. We invested a lot of effort and time to create the content, please respect our work!