ST Nucleo WL55JC
The Nucleo-WL55JC is a development board for the STM32WL55 SoC from ST. It features 64 I/O, 3 onboard LEDs and buttons, integrated stlink for easy debug and flashing and on-board LoRa receiver with external antenna. NSH can be easily access via virtual serial port from usb.
Features
STM32WL55JC MCU, 256K FLASH, 64K SRAM
32768 Hz LSE crystal
32 MHz HSE crystal
Embedded stlink-v3 debugger (debug/flash and virtual serial port)
Reset button
3 user programmable LEDs
3 user programmable buttons
Power indicator LED
LoRa radio with antenna
64 Nucleo I/O
Arduino compatible pinout
Pin Mapping
Pin mapping can be altered by (de)soldering bridges, by default board uses following mapping:
Pin |
Signal |
Notes |
|---|---|---|
PA2 |
LPUART1 TX |
Virtual serial port over usb |
PA3 |
LPUART2 RX |
Virtual serial port over usb |
PB6 |
USART1 TX |
D1 on Arduino pinout |
PB7 |
USART1 RX |
R0 on Arduino pinout |
PA0 |
Button 1 |
|
PA1 |
Button 2 |
|
PC6 |
Button 3 |
|
PB15 |
Blue LED |
Active HIGH |
PB11 |
Red LED |
Active HIGH |
PB9 |
Green LED |
Active HIGH |
Default Peripherals Configuration
LED
Green and Red LEDs are used by the system at boot to show system state. Once system is booted these LEDs are for user to control. When CONFIG_ARCH_LEDS is set, Blue LED is reserved by OS for reporting system status. When CONFIG_ARCH_LEDS is not set, OS state won’t be reported on any of the LEDs and all 3 LEDs are available for user right from the start.
Serial Console
There are 2 serial ports - USART1 and LPUART1.
USART1 is connected to arduino D0/D1 pin and LPUART is connected to stlink that provides virtual serial port.
NSH is configured to use LPUART and virtual serial port. After flashing you can open /dev/ttyACM0 (may change depending on your system) and nsh prompt will be waiting for you there. Serial device does not disappear when flashing and resetting board - it can be left opened and flashing will work without problems.
Configurations
nsh
Basic NuttShell configuration (console enabled in LPUART1, exposed via USB connection, at 115200 bps 8n1).
demo
This configuration contains demonstration code and programs to show what board is capable of. These programs and settings are usually absolutely useless in production code and are here just to show, by example, what you can do with the board.
Flash & Debug
Both flashing and debugging are done using the embedded stlink-v3 debugger. OpenOCD can be invoked in the following way to flash:
openocd -f interface/stlink.cfg -f target/stm32wlx.cfg \
-c "program nuttx.bin exit 0x08000000"
To debug attach openocd to stlink with command:
openocd -f interface/stlink.cfg -f target/stm32wlx.cfg
start gdb:
arm-none-eabi-gdb ./nuttx --tui
attach to gdb server:
target remote localhost:3333
(optionally) reset program and start from the very beginning:
monitor reset halt
Remember to generate debug symbol by setting CONFIG_DEBUG_SYMBOLS and optionally (for more natural flow in gdb step) suppress optimization by setting CONFIG_DEBUG_NOOPT.