SparkFun GPS Breakout (ZOE-M8Q and SAM-M8Q) Hookup Guide

Contributors: Elias The Sparkiest
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SparkFun SAM-M8Q Hardware Overview


Power for this board is 3.3V. There is a 3.3V pin on the PTH header along the side of the board, but you can also provide power through the Qwiic connector.


The small metal disk in the upper left corner is a small lithium battery. This battery does not provide power to the IC like the 3.3V system does, but to relevant systems inside the IC that allow for a quick reconnection to satellites. The time to first fix will about ~29 seconds, but after it has a lock, that battery will allow for a one second time to first fix. This is known as a hot start and lasts for four hours after the board is powered down. The battery provides over a years worth of power to the backup system and charges slowly when the board is powered.

Pictured is the small battery on the upper left side of the board, if the board is oriented with the two Qwiic connectors on the sides.


There's a single red power LED just above the Qwiic connector to indicate that the board is powered. There is another LED labeled PPS that is connected to the Pulse Per Second line on the GPS chip. When connected to a satellite, this line generates a pulse that is synchronized with a GPS or UTC time grid. By default, you'll see one pulse a second.

Pictured is the power LED on the right side just above one of the Qwiic connectors and the PPS LED on the left side of the board just below the other Qwiic connector.


There are three jumpers on the topside of the product, each labeled with its function. At the bottom right of the picture is a three way jumper labeled I²C that connects two pull-up resistors to the I2C data lines. If you have many devices on your I2C data lines, then you may consider cutting these. Just above that jumper is the JP2 jumper. If you cut this trace it will disconnect the Power LED just above the Qwiic connector. Finally, on the left side of the product is the JP1 jumper that when cut disconnects the PPS LED.

This picture highlights two jumpers, one on the right labeled "JP1" and another on the left named "JP2". Orientation is Qwiic connectors on a horizontal plane.

Chip Antenna

This GPS unit at the center of the PCB may look a bit funky to you. In fact you may be thinking, "Wow, that looks suspiciously like a GNSS Antenna....". That's very astute dear hookup guide peruser. This GPS IC is actually built into the antenna giving you an all-in-one GPS solution.

This picture highlights the large chip at the center of the board that is a large GNSS chip antenna.

FTDI Header

At the top of the board, we have the traditional pinout for an FTDI header. Make sure that the FTDI that you use is 3.3V and not 5V!

This picture highlights the FTDI header at the top of the board that mates directly with any standart FTDI pinout.

Qwiic and I2C

At the opposite side of the board. There are two pins labeled SDA and SCL which indicates the I2C data lines. Similarly, you can use either of the Qwiic connectors to provide power and utilize I2C. The Qwiic ecosystem is made for fast prototyping by removing the need for soldering. All you need to do is plug a Qwiic cable into the Qwiic connector and voila!

This picture highlights the two Qwiic connectors and the I2C header at the bottom of the board. The four lower right through holes are the I2C pins. Orientation of the board is the two Qwiic connectors on a horizontal plane with the battery at the top left.

Broken Out Pins

There are four other pins broken out: Pulse per second PPS, Reset RST, Safeboot SAFE, and finally the interrupt pin INT. The first pin PPS outputs pulse trains synchronized with the GPS or UTC time grid. The signal defaults to once per second but is configurable over a wide range. Read the u-blox Receiver Protocol Specification in the Resources tab for more information. The reset pin resets the chip. The next pin, SAFE is used to start up the IC in safe boot mode. The final pin INT can be used to wake the chip from power save mode.

This picture highlights the other through holes on the lower left of the board that breaks out functional pins of the GPS unit.

GPS Capabilities

The SAM-M8 is able to connect to up to three different GNSS constellations at a time making it very accurate for its size. Below are the listed capabilities of the GPS unit.

Horizontal Position Accuracy 2.5m2.5m8m---
Max Navigation Update Rate ROM 10Hz 18Hz 18Hz 18Hz
Time-To-First-Fix Cold Start 26s 29s 30s ---
Hot Start 1s 1s 1s ---
SensitivityTracking and Navigation -165dBm -164dBm -164dBm -157dBm
Reacquisition -158dBm -158dBm -154dBm -151dBm
Cold Start-146dBm -146dBm -143dBm -136dBm
Hot Start -155dBm -155dBm -154dBm -149dBm
Velocity Accuracy 0.05m/s
Heading Accuracy 0.3 degrees

Board Dimensions

The board is 1.6"x1.6", which is slightly bigger than a typical Qwiic board. The board includes four mounting holes on each corner of the board.

Board Dimensions