STMicroelectronics B-U585I-IOT02A board

This project is a simple Fault component example running on Arm Cortex-M33 microcontroller on a STMicroelectronics B-U585I-IOT02A evaluation board.

The application allows triggering of specific faults upon which the fault information is saved and system is reset. When system restarts the fault information is output via the Event Recorder and via the STDIO.

The fault information can also be inspected with Component Viewer in a debug session.

Prerequisites

Software:

• Keil MDK v5.38 or newer containing:
  • Arm Compiler 6 (part of the MDK)
• STM32CubeMX v6.8.1 or newer with:
  • STM32Cube MCU Package for STM32U5 Series v1.2.0
• STM32CubeProgrammer utility

CMSIS Packs:

• Required packs:
  • ARM::CMSIS-View v1.0.0 or newer
  • ARM::CMSIS-Compiler v1.0.0 or newer
  • ARM::CMSIS v5.9.0 or newer
  • Keil::STM32U5xx_DFP v2.1.0 or newer
  • Keil::B-U585I-IOT02A_BSP v1.0.0 or newer

Hardware:

This board has to be properly configured with TrustZone enabled.

Please follow the steps below carefully:

Configure the following Option bytes with STM32CubeProgrammer utility:

• User Configuration:
  • TZEN: checked
  • DBANK: checked
• Boot Configuration:
  • SECBOOTADD0: Value = 0x1800 Address = 0x0c000000
• Secure Area 1:
  • SECWM1_PSTRT: Value = 0x0 Address = 0x08000000
  • SECWM1_PEND: Value = 0x7f Address = 0x080fe000
• Write Protection 1:
  • WRP1A_PSTRT: Value = 0x7f Address = 0x080fe000
  • WRP1A_PEND: Value = 0x0 Address = 0x08000000
• Secure Area 1:
  • SECWM2_PSTRT: Value = 0x7f Address = 0x08000000
  • SECWM2_PEND: Value = 0x0 Address = 0x08100000
• Write Protection 1:
  • WRP2A_PSTRT: Value = 0x7f Address = 0x081fe000
  • WRP2A_PEND: Value = 0x0 Address = 0x08100000

Build and Run

To try the example do the following steps:

1. Open the Fault.uvmpw in the uVision
2. Build the Project: Fault_S project
3. Build the Project: Fault_NS project
4. Download the built application to the MCU's Flash
5. Open the Serial Terminal application and connect to the STMicroelectronics STLink Virtual COM Port (COMx) (115200-8-N-1)
6. Press RESET button on the board
7. Follow the instructions in the Serial Terminal and observe the results

Note: In the debug session fault information can be inspected in the Component View and Event Recorder windows

The fault triggering is done by entering a number via Serial Terminal application (see possible values below).

• 0: terminate the example
• 1: trigger the Non-Secure fault, Non-Secure data access Memory Management fault
• 2: trigger the Non-Secure fault, Non-Secure data access Bus fault
• 3: trigger the Non-Secure fault, Non-Secure undefined instruction Usage fault
• 4: trigger the Non-Secure fault, Non-Secure divide by 0 Usage fault
• 5: trigger the Secure fault, Non-Secure data access from Secure RAM memory
• 6: trigger the Secure fault, Non-Secure instruction execution from Secure Flash memory
• 7: trigger the Secure fault, Secure undefined instruction Usage fault

Example details

Clock Settings:

• XTAL = MSIS = 4 MHz
• Core = 160 MHz

The example contains 2 applications: Secure and Non-Secure.

Secure application (bare-metal, no RTOS):

• setups the system (clocks, power, security and privilege rights (GTZC), caching) according to the CubeMX configuration
• provides a function for triggering a fault on the Secure side

Non-Secure application (uses RTX RTOS and Standard C Library):

• setups the peripherals used by the non-secure application (LEDs, button, UART1) according to the CubeMX configuration
• it runs 2 threads:
  • 'AppThread' thread: Blink Green LED with 1 second interval
  • 'FaultTriggerThread' thread: Trigger a fault according to input from the STDIO

When a fault is triggered the fault handler saves the fault information with the ARM_FaultSave function. When valid fault information exists it can be viewed with Component Viewer or with ARM_FaultRecord function the fault information can be output to the Event Recorder or with the ARM_FaultPrint function it can be output to the STDIO.