Wio Tracker L1

Overview

The Seeed Studio Wio Tracker L1 is a LoRa + GNSS tracker based on a Nordic Semiconductor nRF52840. The board is sold as a Meshtastic node, with optional variants (notably the L1 Pro) that bundle the same signal board with an enclosure and an integrated battery.

For more information, see the Wio Tracker L1 product page [1] and the Wio Tracker L1 wiki [2].

Hardware

The Wio Tracker L1 signal board carries:

  • Nordic Semiconductor nRF52840 (ARM Cortex-M4F, 1 MB flash / 256 kB RAM, Bluetooth 5 and IEEE 802.15.4 transceiver, native USB 2.0 full-speed).

  • Semtech SX1262 LoRa modem (862-930 MHz) with TCXO (DIO3, 1.8 V) and an RF switch driven by DIO2 plus a separate LNA-enable line on P1.08.

  • Quectel L76K GNSS receiver (GPS / BeiDou) on UART0 at 9600 baud.

  • 16 Mbit Puya P25Q16H QSPI flash.

  • 1.3” SH1106 OLED on the primary I2C bus.

  • External Grove I2C connector on TWIM1.

  • One user LED, one user button, a buzzer (PWM), a 5-way trackball and a battery voltage divider gated by a control GPIO.

  • USB Type-C connector wired to the nRF52840 native USB peripheral.

Connections and IOs

Pin

Direction

Function

Usage

P1.01

OUT

GPIO

User LED (active high)

P0.08

IN

GPIO

User Button (active low)

P0.30

OUT

SPIM3 SCK

SX1262 LoRa SCK

P0.03

IN

SPIM3 MISO

SX1262 LoRa MISO

P0.28

OUT

SPIM3 MOSI

SX1262 LoRa MOSI

P1.14

OUT

GPIO

SX1262 NSS (chip select)

P0.07

IN

GPIO

SX1262 DIO1 (IRQ)

P1.10

IN

GPIO

SX1262 BUSY

P1.07

OUT

GPIO

SX1262 RESET (active low)

P1.08

OUT

GPIO

SX1262 RX-enable

P0.27

OUT

UART0 TX

L76K GNSS RX

P0.26

IN

UART0 RX

L76K GNSS TX

P0.05

OUT

TWIM0 SCL

SH1106 OLED I2C

P0.06

I/O

TWIM0 SDA

SH1106 OLED I2C

P1.11

I/O

TWIM1 SDA

Grove I2C SDA

P1.12

OUT

TWIM1 SCL

Grove I2C SCL

P1.04

IN

GPIO

Trackball Up

P0.12

IN

GPIO

Trackball Down

P0.11

IN

GPIO

Trackball Left

P1.03

IN

GPIO

Trackball Right

P1.05

IN

GPIO

Trackball Press

P1.00

OUT

PWM0 OUT0

Buzzer

P0.04

OUT

GPIO

Battery divider enable

P0.31

AIN7

ADC

Battery voltage sense

P0.21

OUT

QSPI SCK

Puya P25Q16H flash

P0.20

I/O

QSPI IO0

Puya P25Q16H flash

P0.24

I/O

QSPI IO1

Puya P25Q16H flash

P0.22

I/O

QSPI IO2

Puya P25Q16H flash

P0.23

I/O

QSPI IO3

Puya P25Q16H flash

P0.25

OUT

QSPI CSn

Puya P25Q16H flash

Supported Features

The wio_tracker_l1 board supports the hardware features listed below.

on-chip / on-board
Feature integrated in the SoC / present on the board.
2 / 2
Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files.
vnd,foo
Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.

Programming and Debugging

The wio_tracker_l1 board supports the runners and associated west commands listed below.

flash debug

The Wio Tracker L1 ships with a pre-installed Adafruit nRF52 bootloader that exposes a UF2 USB Mass Storage interface when the user double-taps the RST button. The volume identifies itself as Seeed TRACKER L1 with Board-ID TRACKER L1 (see INFO_UF2.TXT on the mounted volume). The default Zephyr workflow relies on this bootloader, so no external SWD probe is required for day-to-day development.

Warning

The bootloader lives in the top 48 kB of flash and is what makes the USB-only flashing flow possible. Erasing it (for example via an external SWD probe and nrfjprog --eraseall) is a one-way trip without that probe: USB recovery will no longer work and the bootloader UF2 must be re-flashed through the SWD pads on the rear of the board.

Flashing

  1. Build the application; the build system produces build/zephyr/zephyr.uf2 because CONFIG_BUILD_OUTPUT_UF2 is enabled by default for this board.

  2. Double-tap the RST button. The board re-enumerates as a USB MSC volume titled WTL1BOOT (or similar, depending on the bootloader revision).

  3. Run west flash. The uf2 runner copies zephyr.uf2 onto the mounted volume; the bootloader writes the image and resets into the application.

Alternatively, drag and drop zephyr.uf2 onto the volume manually.

board.cmake already passes --board-id="TRACKER L1" so that the runner picks the Wio Tracker L1 when multiple UF2-capable devices are mounted at once. Should the bootloader ever be rebuilt with a different Board-ID, override the default on the command line:

west flash --runner uf2 --board-id "<Board-ID from INFO_UF2.TXT>"

Building and flashing the Blinky sample is the recommended smoke test:

# From the root of the zephyr repository
west build -b wio_tracker_l1 samples/basic/blinky
west flash

References