STM32WL family

st.com STM32WL family page

This ST MCU family is dual-core : based on an Arm Cortex-M4 core and an Arm Cortex-M0+ core.

Only M4 core is currently used by mbed-os applications.

• Supported boards
  • NUCLEO_WL55JC
  • CUSTOM boards
• LoRa
  • MBED-OS support
  • baremetal support
  • Antenna configuration
  • GPIO debug pins
  • mbed-os test
  • Application example

Supported boards

NUCLEO_WL55JC

st.com STM32WL5x MCU page

st.com NUCLEO page

mbed.com NUCLEO page

• Total FLASH is 256KB
• RAM: 64 KB

CUSTOM boards

Check https://github.com/ARMmbed/stm32customtargets

LoRa

MBED-OS support

Lora radio is enabled in default STM32WL configuration

baremetal support

Baremetal is supported.

mbed_app.json:

{
    "requires": ["bare-metal", "stm32wl-lora-driver"]
}

Antenna configuration

NUCLEO HW configuration is provided as the default configuration.

https://github.com/ARMmbed/mbed-os/blob/master/connectivity/drivers/lora/TARGET_STM32WL/STM32WL_radio_driver.cpp#L23

MBED_WEAK void set_antenna_switch(RBI_Switch_TypeDef state)

So you can overwrite it for your custom board.

GPIO debug pins

2 pins can be configured to check RX and TX activity.

Example of mbed_app.json:

{
    "target_overrides": {
        "NUCLEO_WL55JC": {
            "stm32wl-lora-driver.debug_rx": "LED1",
            "stm32wl-lora-driver.debug_tx": "LED2"
        }
    }
}

mbed-os test

Application example

https://github.com/ARMmbed/mbed-os-example-lorawan/