/** @page SPI_FullDuplex_ComIT SPI Full Duplex IT example @verbatim ******************** (C) COPYRIGHT 2017 STMicroelectronics ******************* * @file SPI/SPI_FullDuplex_ComIT/readme.txt * @author MCD Application Team * @brief Description of the SPI Full Duplex IT example. ****************************************************************************** * @attention * * Copyright (c) 2017 STMicroelectronics. * All rights reserved. * * This software is licensed under terms that can be found in the LICENSE file * in the root directory of this software component. * If no LICENSE file comes with this software, it is provided AS-IS. * ****************************************************************************** @endverbatim @par Example Description This example shows how to ensure SPI data buffer transmission/reception between two boards by using an interrupt. The communication is done with 2 boards through SPI. _________________________ _________________________ | ______________| |______________ | | |SPI2 | | SPI2| | | | | | | | | | CLK(PB13)|______________________|(PB13)CLK | | | | | | | | | | MISO(PB14)|______________________|(PB14)MISO | | | | | | | | | | MOSI(PB15)|______________________|(PB15)MOSI | | | | | | | | | |______________| |______________| | | __ | | __ | | |__| | | |__| | | USER | | USER | | GND|______________________|GND | | | | | |_STM32F401 ______________| |_STM32F401 ______________| This example guides you through the different configuration steps by mean of HAL API to ensure SPI Data buffer transmission and reception using Interrupt. HAL architecture allows user to easily change code to move to DMA or Polling mode. To see other communication modes please check following examples: SPI/SPI_FullDuplex_ComDMA SPI/SPI_FullDuplex_ComPolling At the beginning of the main program the HAL_Init() function is called to reset all the peripherals, initialize the Flash interface and the systick. Then the SystemClock_Config() function is used to configure the system clock (SYSCLK) to run at 84 MHz. The SPI peripheral configuration is ensured by the HAL_SPI_Init() function. This later is calling the HAL_SPI_MspInit()function which core is implementing the configuration of the needed SPI resources according to the used hardware (CLOCK, GPIO and NVIC). You may update this function to change SPI configuration. The SPI communication is then initiated. The HAL_SPI_TransmitReceive_IT() function allows the reception and the transmission of a predefined data buffer at the same time (Full Duplex Mode) The user can choose between Master and Slave through "#define MASTER_BOARD" in the "main.c" file. If the Master board is used, the "#define MASTER_BOARD" must be uncommented. If the Slave board is used the "#define MASTER_BOARD" must be commented. For this example the aTxBuffer is predefined and the aRxBuffer size is same as aTxBuffer. In a first step after the user press the User Key, SPI Master starts the communication by sending aTxBuffer and receiving aRxBuffer through HAL_SPI_TransmitReceive_IT(), at the same time SPI Slave transmits aTxBuffer and receives aRxBuffer through HAL_SPI_TransmitReceive_IT(). The end of this step is monitored through the HAL_SPI_GetState() function result. Finally, aRxBuffer and aTxBuffer are compared through Buffercmp() in order to check buffers correctness. STM32 Discovery boards LEDs can be used to monitor the transfer status: - LED3 toggles on master board waiting user button to be pressed. - LED4 turns ON when the transmission process is complete. - LED6 turns ON when the reception process is complete. - LED5 turns ON when there is an error in transmission/reception process. @note SPIx instance used and associated resources can be updated in "main.h" file depending hardware configuration used. @note You need to perform a reset on Slave board, then perform it on Master board to have the correct behaviour of this example. @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, SPI, Full-duplex, Interrupt, Transmission, Reception, Master, Slave, MISO, MOSI @par Directory contents - SPI/SPI_FullDuplex_ComIT/Inc/stm32f4xx_hal_conf.h HAL configuration file - SPI/SPI_FullDuplex_ComIT/Inc/stm32f4xx_it.h SPI interrupt handlers header file - SPI/SPI_FullDuplex_ComIT/Inc/main.h Main program header file - SPI/SPI_FullDuplex_ComIT/Src/stm32f4xx_it.c SPI interrupt handlers - SPI/SPI_FullDuplex_ComIT/Src/main.c Main program - SPI/SPI_FullDuplex_ComIT/Src/system_stm32f4xx.c STM32F4xx system clock configuration file - SPI/SPI_FullDuplex_ComIT/Src/stm32f4xx_hal_msp.c HAL MSP module @par Hardware and Software environment - This example runs on STM32F401xCx devices. - This example has been tested with STM32F401-Discovery RevB board (MB1115B) and can be easily tailored to any other supported device and development board. - STM32F401-Discovery RevB Set-up - Connect Master board PB13 to Slave Board PB13 - Connect Master board PB14 to Slave Board PB14 - Connect Master board PB15 to Slave Board PB15 - Connect Master board GND to Slave Board GND @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 o Uncomment "#define MASTER_BOARD" and load the project in Master Board o Comment "#define MASTER_BOARD" and load the project in Slave Board - Run the example */