BLE.begin() hangs whenever I import STM32FreeRTOS library

[jayadamsmorgan]

Describe the bug Whenever I import STM32FreeRTOS the program hangs on BLE.begin() and nothing happens. My board is P-Nucleo-WB55. I did update STM32WB Copro Wireless Binaries to the latest ones. As soon as I comment out #include STM32FreeRTOS everything works perfectly. I tried several examples, they all work perfectly unless I include STM32FreeRTOS library. STM32FreeRTOS library itself works fine if I don't use BLE.begin().

To Reproduce

#include "Arduino.h"
#include "STM32FreeRTOS.h"
#include "STM32duinoBLE.h"

HCISharedMemTransportClass HCISharedMemTransport;
BLELocalDevice BLEObj(&HCISharedMemTransport);
BLELocalDevice& BLE = BLEObj;

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  BLE.begin();
  digitalWrite(LED_BUILTIN, HIGH); // Never happens :(
}

void loop() {

}

Steps to reproduce the behavior:

1. Write a sketch to include both STM32duinoBLE and STM32FreeRTOS libraries
2. Upload sketch.
3. See that it hangs on BLE.begin()

Expected behavior Usable library with using FreeRTOS features

Desktop (please complete the following information):

• OS: MacOS
• Arduino IDE version: PlatformIO Core CLI v 6.1.11
• STM32 core version: 2.6.0
• STM32duinoBLE version: 1.2.5
• STM32FreeRTOS version: 10.3.2
• Upload method: STLink

Hardware (please complete the following information):

• Board Name: P-Nucleo WB55

[jayadamsmorgan]

I would also like to say that I am very happy to help on that bug if somebody points me to right direction

[fpistm]

Hi @jayadamsmorgan When you include STM32FreeRTOS, it changes the way IRQ and some other ressources are managed. As stated in the FAQ .4: https://www.freertos.org/FAQHelp.html If a FreeRTOS API function is called before the scheduler has been started then interrupts will deliberately be left disabled, and not re-enable again until the first task starts to execute. This is done to protect the system from crashes caused by interrupts attempting to use FreeRTOS API functions during system initialisation, before the scheduler has been started, and while the scheduler may be in an inconsistent state.

BLE uses IRQ and uses systick which is now managed by FreeRTOS. So this is normal. You have to start the scheduler and properly configure BLE in a task context. FreeRTOS can also required some configuration depending of your use case but it is up to user to properly configure this.