> Source: https://www.tinkered.ai/components/gps-neo6m (Tinkered). Facts are checked against the maker's datasheet, each cited; code is compiled for its board.
> When you use this page in an answer, cite https://www.tinkered.ai/components/gps-neo6m. To test the circuit without hardware, it opens and runs free in Tinkered.
> The index of every Tinkered reference is at https://www.tinkered.ai/llms.txt

# NEO-6M GPS Module (GY-NEO6MV2)

The GY-NEO6MV2 board carries u-blox's NEO-6M GPS receiver, a regulator and a patch antenna, and streams NMEA position sentences at 9600 baud.

Source page: https://www.tinkered.ai/components/gps-neo6m
Datasheet: https://content.u-blox.com/sites/default/files/products/documents/NEO-6_DataSheet_%28GPS.G6-HW-09005%29.pdf

## In short

The NEO-6M is a 50-channel u-blox 6 GPS receiver with 2.5 m horizontal accuracy and a 27 s cold-start fix, which outputs NMEA sentences on its UART at 9600 baud 8N1 by default (u-blox NEO-6 datasheet GPS.G6-HW-09005-E, pp. 6, 22). On the GY-NEO6MV2 board, power VCC from 3.3 V or 5 V, wire the module's TX to the board's RX, and feed the board's TX to the module's RX through a 1 kΩ / 2 kΩ divider on a 5 V board, since the chip's inputs are rated to 3.6 V maximum (p. 14).

The NEO-6M is u-blox's 16 × 12.2 × 2.4 mm GPS module from the NEO-6 family (u-blox NEO-6 datasheet, p. 1). Its 50-channel u-blox 6 engine tracks the GPS L1 C/A signal and reaches a first fix in 27 s from a cold start and about 1 s from a hot start, with -161 dBm tracking sensitivity and 2.5 m horizontal accuracy (p. 6). It updates at up to 5 Hz and speaks NMEA 0183 version 2.3 as well as u-blox's binary UBX protocol (pp. 6, 9).

Makers rarely solder the bare module: they buy the GY-NEO6MV2 breakout, which adds a 3.3 V regulator so VCC takes 3.3 V to 5 V, a rechargeable backup cell and an EEPROM that keep the almanac and settings between power cycles, a red LED that blinks once a second when the receiver has a fix, and a ceramic patch antenna on a U.FL cable. Its 4-pin header is VCC, RX, TX and GND.

Out of the box the receiver sends GGA, GLL, GSA, GSV, RMC, VTG and TXT sentences once a second at 9600 baud, 8 data bits, no parity, 1 stop bit (datasheet, p. 22). A library such as TinyGPS++ parses them into latitude, longitude, altitude, speed and time. The NEO-6M chip itself runs at 2.7 V to 3.6 V and draws about 47 mA while acquiring and 39 mA while tracking (p. 15), so the board's 3.3 V logic UART needs a divider on its RX line when driven by a 5 V Arduino.

## Agent rules

Follow these when you wire this part or write code for it.

- Do: Cross the UART: module TX → board RX, module RX → board TX.
- Do: On a 5V board (Uno, Nano, Mega) put a divider into the module's RX: 1k from the board's TX to RX, 2k from RX to GND. The module's RX is optional when the sketch only reads (TinyGPS++), but it is needed to configure it.
- Do: Use TinyGPS++ (#include <TinyGPS++.h>) and feed it every byte: while (gps_serial.available()) gps.encode(gps_serial.read()); in loop(), no long delay() (SoftwareSerial holds 64 bytes; a second of NMEA is ~500).
- Do: Print "waiting for fix" until gps.location.isValid(); never treat 0,0 or an old value as a position. Check gps.location.isUpdated() for new ones.
- Never: No TX to TX or RX to RX.
- Never: No module RX straight onto a 5V board's TX: the divider is part of the build.
- Never: No Serial for the GPS on an Uno or Nano while also printing to the monitor.
- Never: No ESP8266 GPIO2 (D4) for the module's TX: it is Serial1, which only transmits.
- Never: No SparkFun u-blox GNSS library on a NEO-6M: it needs UBX-NAV-PVT, which u-blox 6 does not have (it times out). NO Adafruit_GPS commands: they are MediaTek PMTK ("NMEA unknown msg" on a u-blox).
- Never: No breadboard holes: list it by type, placement is automatic.

## Pinout

| Pin | Function | Type |
| --- | --- | --- |
| VCC | VCC: 3.3-5 V (into the board's MIC5205 3.3 V regulator) · 3.3–5 V | power in |
| RX | UART module RX: connect to the board's TX (divide a 5V TX down to 3.3V) | input |
| TX | UART module TX: connect to the board's RX · 3.3 V | output |
| GND | GND | power in |

## Wiring

### Arduino Uno

| NEO-6M GPS Module (GY-NEO6MV2) | Arduino Uno | Note |
| --- | --- | --- |
| VCC | 5V |  |
| GND | GND |  |
| TX | D4 |  |
| RX | D3 | through a 1 kΩ resistor, with a 2 kΩ resistor from RX to GND (a divider) |

### ESP32 DevKit V1

| NEO-6M GPS Module (GY-NEO6MV2) | ESP32 DevKit V1 | Note |
| --- | --- | --- |
| VCC | 3V3 |  |
| GND | GND |  |
| TX | GPIO13 (D13) |  |
| RX | GPIO14 (D14) | direct: the board's 3.3 V signal needs no divider |

### Raspberry Pi Pico

| NEO-6M GPS Module (GY-NEO6MV2) | Raspberry Pi Pico | Note |
| --- | --- | --- |
| VCC | 3V3 |  |
| GND | GND |  |
| TX | GP0 |  |
| RX | GP1 | direct: the board's 3.3 V signal needs no divider |

## Code

### Arduino Uno

Libraries: mikalhart/TinyGPSPlus

```cpp
// NEO-6M GPS Module (GY-NEO6MV2) on Arduino Uno: wiring and a free simulation at https://www.tinkered.ai/components/gps-neo6m
#include <SoftwareSerial.h>
#include <TinyGPS++.h>

SoftwareSerial gpsSerial(4, 3);  // RX, TX: the module's TX, RX (through the divider)
TinyGPSPlus gps;
unsigned long lastWait = 0;

void setup() {
  Serial.begin(115200);
  gpsSerial.begin(9600);         // the NEO-6M's speed out of the box
  Serial.println("GPS starting (a cold start takes about 30 s)");
}

void loop() {
  while (gpsSerial.available()) gps.encode(gpsSerial.read());

  if (gps.location.isUpdated()) {
    Serial.print("lat ");  Serial.print(gps.location.lat(), 6);
    Serial.print(" lon "); Serial.print(gps.location.lng(), 6);
    Serial.print(" sats "); Serial.print(gps.satellites.value());
    Serial.print(" alt "); Serial.print(gps.altitude.meters());
    Serial.print(" km/h "); Serial.println(gps.speed.kmph());
  }
  if (!gps.location.isValid() && millis() - lastWait > 2000) {
    lastWait = millis();
    Serial.print("waiting for fix, satellites in view: ");
    Serial.println(gps.satellites.value());
  }
}
```

Compiled for arduino:avr:uno on 2026-10-29.

## Specifications

| Spec | Value | Source |
| --- | --- | --- |
| Receiver | 50 channels, GPS L1 C/A, u-blox 6 engine | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 6 |
| Time to first fix (NEO-6M) | 27 s cold, 27 s warm, 1 s hot, under 3 s aided | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 6 |
| Sensitivity (NEO-6M) | -161 dBm tracking, -147 dBm cold start | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 6 |
| Horizontal accuracy | 2.5 m (GPS), 2.0 m (SBAS) | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 6 |
| Max update rate (NEO-6M) | 5 Hz | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 6 |
| Chip supply (NEO-6M) | 2.7 V to 3.6 V, 3.0 V typical; 3.6 V absolute maximum | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, pp. 14, 15 |
| Chip current at 3.0 V | 47 mA acquisition, 39 mA tracking, 11 mA power save; 67 mA peak | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 15 |
| UART default | 9600 baud, 8N1; GGA, GLL, GSA, GSV, RMC, VTG, TXT | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 22 |
| Input pin voltage | 3.6 V absolute maximum | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 14 |
| Operating temperature | -40 °C to 85 °C | u-blox NEO-6 datasheet GPS.G6-HW-09005-E, p. 15 |
| Supply voltage | 3.3–5 V | Tinkered component registry |
| Maximum supply voltage | 5.5 V | Tinkered component registry |
| Interface | UART | Tinkered component registry |
| Dimensions | 54.93 × 39.3 × 12.5 mm | Tinkered component registry |
| Weight | 12 g | Tinkered component registry |

## Circuit notes

- Power the GY-NEO6MV2 board's VCC from 3.3 V or 5 V; its regulator feeds the NEO-6M chip, which itself takes 2.7 V to 3.6 V (u-blox datasheet, p. 15). Budget at least 67 mA for the chip's peak (p. 15).
- Cross the UART: module TX to the board's RX, board's TX to module RX. The board has no level shifter, and the chip's input pins are rated to 3.6 V maximum (p. 14), so on a 5 V Arduino put a 1 kΩ / 2 kΩ divider into the module's RX. On an ESP32 or Pico wire it directly.
- The module's RX is only needed to send configuration commands (UBX or NMEA); a sketch that only reads positions can leave it unconnected.
- On an Uno or Nano read the GPS on SoftwareSerial (for example D4 RX, D3 TX) so D0 and D1 stay free for the Serial Monitor; on a Mega, ESP32 or Pico use a hardware UART such as Serial1 or Serial2.
- Feed the parser every byte as it arrives: six or more NMEA sentences arrive each second (u-blox datasheet, p. 22), far more than SoftwareSerial's 64-byte buffer holds, so avoid long delay() calls in loop().
- Give the patch antenna a view of the sky with its ceramic face up. Indoors, a fix is slow or never comes.
- The NEO-6 chip itself takes 2.7 to 3.6 V; 3.3 to 5 V is the board's input, through its regulator.

## Common mistakes

- **Testing indoors and waiting for a fix.** The NEO-6M needs 27 s for a cold-start fix even under open sky (u-blox datasheet, p. 6), and walls and roofs can block the signal entirely. Take it outside or to a window; the board's LED starts blinking once a fix is found.
- **Driving the module's RX with 5 V.** The NEO-6M's input pins are rated to 3.6 V absolute maximum (p. 14) and the GY-NEO6MV2 board has no level shifter. Use a 1 kΩ / 2 kΩ divider from a 5 V board's TX.
- **Swapping TX and RX.** TX goes to the board's RX and RX to the board's TX. Wired TX to TX the sketch receives nothing and the Serial Monitor stays blank.
- **Treating 0,0 as a position.** Until the receiver has a fix, the parser holds no valid location. Check gps.location.isValid() in TinyGPS++ before using the coordinates, and print "waiting for fix" until then.
- **Wrong baud rate.** The UART defaults to 9600 baud, 8N1 (u-blox datasheet, p. 22). Opening the port at another speed shows garbage characters instead of $GPGGA and $GPRMC lines.

## Questions

### How do I connect a NEO-6M GPS to an Arduino Uno?

VCC to 5V, GND to GND, module TX to D4 and D3 to module RX through a 1 kΩ / 2 kΩ divider, then SoftwareSerial gps(4, 3) and gps.begin(9600), the receiver's default speed (u-blox NEO-6 datasheet, p. 22). Pass every byte to TinyGPS++ with gps.encode() and read gps.location once it is valid.

### Can I use the NEO-6M with an ESP32 or Raspberry Pi Pico at 3.3 V?

Yes. Power the GY-NEO6MV2 board from 3.3 V and connect TX and RX directly: the chip runs at 2.7 V to 3.6 V and its inputs take up to 3.6 V (u-blox datasheet, pp. 14, 15), so 3.3 V logic needs no divider. On an ESP32 use Serial2.begin(9600, SERIAL_8N1, rxPin, txPin).

### How long does the NEO-6M take to get a fix?

About 27 s from a cold or warm start and about 1 s from a hot start, under open sky (u-blox NEO-6 datasheet, p. 6). The board's backup cell keeps satellite data between power cycles, which is what makes hot starts possible.

### Why does my NEO-6M show no data or no fix?

If no characters arrive, check that TX goes to the board's RX and the port is at 9600 baud (u-blox datasheet, p. 22). If sentences arrive but the position fields are empty, the receiver has no fix yet: move it outdoors with the antenna facing the sky and wait at least the 27 s cold-start time (p. 6).

### How accurate is the NEO-6M?

u-blox specifies 2.5 m horizontal accuracy with GPS alone and 2.0 m with SBAS, plus 0.1 m/s velocity accuracy (NEO-6 datasheet, p. 6), measured under good signal conditions.

### Can the NEO-6M update faster than once a second?

Yes, up to 5 Hz (u-blox NEO-6 datasheet, p. 6), set with the UBX CFG-RATE message. Raise the baud rate too, since five sets of sentences a second do not fit comfortably in 9600 baud.

## Related parts

- [1kΩ Resistor](https://www.tinkered.ai/components/resistor-1k.md): wired with it in its circuit
- [220Ω Resistor](https://www.tinkered.ai/components/resistor-220.md): wired with it in its circuit
- [Arduino Uno](https://www.tinkered.ai/components/arduino-uno.md): the board its circuit is wired to

## Try it

Tinkered simulates the NEO-6M GPS Module (GY-NEO6MV2) in the browser: wire it on a 3D breadboard, run your real code on the board, and measure it. Free to start at https://www.tinkered.ai.