96Boards WisTrio

Overview

96Boards WisTrio LoRa Tracker board is based on the RAK Wireless RAK5205 chipset integrating SX1276 LoRaWAN Modem, STM32L151CB-A MCU and GPS module. Zephyr applications use the 96b_wistrio configuration to run on these boards.

96Boards WisTrio

Fig. 57 96Boards WisTrio

This board is one of the 96Boards IoT Edition platforms providing LoRa connectivity.

Hardware

96Boards WisTrio provides the following hardware components:

  • RAK5205 Chipset

  • 3.3V work voltage

  • 128 KB Flash

  • 16 KB SRAM

  • On board sensors:

    • Accelerometer: STMicro LIS3DH

    • Integrated Environmental sensor: Bosch BME680

  • 2 User LEDs

  • GPIO with external interrupt capability

  • UART (2)

  • I2C (1)

  • GPS Module

  • GPS Antenna

  • LoRa Antenna

Supported Features

The Zephyr 96b_wistrio board configuration supports the following hardware features:

Interface

Controller

Driver/Component

NVIC

on-chip

nested vector interrupt controller

SYSTICK

on-chip

system clock

UART

on-chip

serial port

GPIO

on-chip

gpio

PINMUX

on-chip

pinmux

I2C

on-chip

i2c

SPI

on-chip

spi

RTC

on-chip

rtc

EEPROM

on-chip

eeprom

The default board configuration can be found in the defconfig file:

boards/arm/96b_wistrio/96b_wistrio_defconfig

Connections and IOs

LED

  • LED1 / User1 LED = PA12

  • LED2 / User2 LED = PB4

Push buttons

  • BUTTON = RST (BT1)

Serial Port

96Boards WisTrio board has 2 UARTs. Zephyr console output is assigned to USART1 with 115200 8N1 as the default setting and USART3 is used for GPS module.

I2C

96Boards WisTrio board has 1 I2C connected to on-board sensors. The default I2C mapping is:

  • I2C1_SCL : PB8

  • I2C1_SDA : PB9

I2C1 also goes to the J22 connector and can be used to attach external sensors.

SPI

96Boards WisTrio board has 1 SPI connected to on-chip LoRa Radio. The default SPI mapping is:

  • SPI1_SCLK : PA5

  • SPI1_MISO : PA6

  • SPI1_MOSI : PA7

  • SPI1_NSS : PB0

Programming and Debugging

Flashing

96Boards WisTrio can be flashed by two methods, one using the ROM bootloader and another using the SWD debug port (which requires additional hardware).

Flashing using the ROM bootloader requires a special activation pattern, which can be triggered by using the BOOT0 pin. The ROM bootloader supports flashing via UART, and I2C but this document describes the UART case only. You can read more about how to enable and use the ROM bootloader by checking the application note AN2606 .

Using ROM bootloader:

  1. Connect 96Boards WisTrio to your Linux PC using, USB-Micro to USB-A cable.

  2. ROM bootloader can be triggered by the following pattern:

    • Connect BOOT0 to VDD (link pin 1 and 2 on J12)

    • Press and release the RST button

More detailed information on activating the ROM bootloader can be found in Chapter 29 of Application note AN2606. The ROM bootloader supports flashing via UART, and I2C protocols.

Here is an example for building and flashing the Hello World application using stm32flash command line utility:

# From the root of the zephyr repository
west build -b 96b_wistrio samples/hello_world
west flash

Using SWD debugger:

Use the Black Magic Debug Probe as an SWD programmer, which can be connected to the SWD pins exposed on the J22 header using its flying leads and its 20 Pin JTAG Adapter Board Kit. When plugged into your host PC, the Black Magic Debug Probe enumerates as a USB serial device as documented on its Getting started page.

It also uses the GDB binary provided with the Zephyr SDK, arm-zephyr-eabi-gdb. Other GDB binaries, such as the GDB from GCC ARM Embedded, can be used as well.

$ arm-zephyr-eabi-gdb -q zephyr.elf
(gdb) target extended-remote /dev/ttyACM0
Remote debugging using /dev/ttyACM0
(gdb) monitor swdp_scan
Target voltage: 3.3V
Available Targets:
No. Att Driver

Debugging

After flashing 96Boards WisTrio, it can be debugged using the same GDB instance. To reattach, just follow the same steps above, till “attach 1”. You can then debug as usual with GDB. In particular, type “run” at the GDB prompt to restart the program you’ve flashed.

References