STM32CubeF4

@verbatim
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
* @file CAN/CAN_LoopBack/readme.txt
* @author MCD Application Team
* @brief Description of the CAN LoopBack example.
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@endverbatim

@par Example Description

How to set up a communication with the CAN in loopback mode.

The CAN cell first performs a transmission and a reception of a standard data
frame by polling at 1 MBit/s. The received frame is checked and some LEDs light
up to indicate whether the communication was successful.

STM32 Eval board's LEDs can be used to monitor the transfer status:
- LED1 is ON when the transfer is complete.
- LED2 is ON when there is a transfer error occurred.
- LED3 is ON when there is an initialization error occurred.

@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.

@note The application needs to ensure that the SysTick time base is always set to 1 millisecond
to have correct HAL operation.

@par Keywords

Connectivity, CAN, Communication, Transmission, Reception, Polling,

@par Directory contents

- CAN/CAN_LoopBack/Inc/stm32f4xx_hal_conf.h HAL configuration file
- CAN/CAN_LoopBack/Inc/main.h Header for main.c module
- CAN/CAN_LoopBack/Inc/stm32f4xx_it.h Interrupt handlers header file
- CAN/CAN_LoopBack/Src/main.c Main program
- CAN/CAN_LoopBack/Src/stm32f4xx_msp.c HAL MSP module
- CAN/CAN_LoopBack/Src/stm32f4xx_it.c Interrupt handlers
- CAN/CAN_LoopBack/Src/system_stm32f4xx.c STM32F4xx system source file

@par Hardware and Software environment

- This example runs on STM32F429xx devices.

- This example has been tested with STM324x9I-EVAL board and can be
easily tailored to any other supported device and development board.

@par How to use it ?

In order to make the program work, you must do the following :
- Open your preferred toolchain
- Rebuild all files and load your image into target memory
- Run the example