149 lines
7.1 KiB
Plaintext
149 lines
7.1 KiB
Plaintext
/**
|
|
@page SPI_FullDuplex_ComPolling SPI Full Duplex Polling example
|
|
|
|
@verbatim
|
|
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
|
|
* @file SPI/SPI_FullDuplex_ComPolling/readme.txt
|
|
* @author MCD Application Team
|
|
* @brief Description of the SPI Full Duplex Polling 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 in Polling
|
|
mode between two boards.
|
|
|
|
The communication is done with 2 boards through SPI.
|
|
_________________________ _________________________
|
|
| ______________| |______________ |
|
|
| |SPI4 | | SPI4| |
|
|
| | | | | |
|
|
| | CLK(PE02)|______________________|(PE02)CLK | |
|
|
| | | | | |
|
|
| | MISO(PE05)|______________________|(PE05)MISO | |
|
|
| | | | | |
|
|
| | MOSI(PE06)|______________________|(PE06)MOSI | |
|
|
| | | | | |
|
|
| |______________| |______________| |
|
|
| __ | | __ |
|
|
| |__| | | |__| |
|
|
| USER | | USER |
|
|
| GND|______________________|GND |
|
|
| | | |
|
|
|_STM32F429i______________| |_STM32F429i______________|
|
|
|
|
This example guides you through the different configuration steps by mean of HAL API
|
|
to ensure SPI Data buffer transmission and reception using Polling.
|
|
|
|
HAL architecture allows user to easily change code to move to IT or DMA mode.
|
|
To see other communication modes please check following examples:
|
|
SPI/SPI_FullDuplex_ComDMA
|
|
SPI/SPI_FullDuplex_ComIT
|
|
|
|
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 180 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). You may update this function to change SPI configuration.
|
|
|
|
The SPI communication is then initiated.
|
|
The HAL_SPI_TransmitReceive() 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(), at the same time SPI Slave transmits aTxBuffer
|
|
and receives aRxBuffer through HAL_SPI_TransmitReceive().
|
|
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. Once done LED3 turns off.
|
|
- LED4 turns ON when there is an error in transmission/reception process
|
|
- LED3 turns ON when the transmission/reception process is complete.
|
|
- LED4 toggle when there is a timeout error in transmission/reception process.
|
|
|
|
@note SPIx instance used and associated resources can be updated in "main.h"
|
|
file depending hardware configuration used.
|
|
|
|
@note Timeout is set to 5 Seconds which means that if no communication occurs
|
|
during 5 Seconds, a Timeout Error will be generated.
|
|
|
|
@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, Polling, Transmission, Reception, Master, Slave, MISO, MOSI
|
|
|
|
@par Directory contents
|
|
|
|
- SPI/SPI_FullDuplex_ComPolling/Inc/stm32f4xx_hal_conf.h HAL configuration file
|
|
- SPI/SPI_FullDuplex_ComPolling/Inc/stm32f4xx_it.h SPI interrupt handlers header file
|
|
- SPI/SPI_FullDuplex_ComPolling/Inc/main.h Main program header file
|
|
- SPI/SPI_FullDuplex_ComPolling/Src/stm32f4xx_it.c SPI interrupt handlers
|
|
- SPI/SPI_FullDuplex_ComPolling/Src/main.c Main program
|
|
- SPI/SPI_FullDuplex_ComPolling/Src/system_stm32f4xx.c STM32F4xx system clock configuration file
|
|
- SPI/SPI_FullDuplex_ComPolling/Src/stm32f4xx_hal_msp.c HAL MSP module
|
|
|
|
|
|
@par Hardware and Software environment
|
|
|
|
- This example runs on STM32F429xx devices.
|
|
|
|
- This example has been tested with STMicroelectronics STM32F429I-Discovery RevC
|
|
boards and can be easily tailored to any other supported device
|
|
and development board.
|
|
|
|
- STM32F429I-Discovery RevC Set-up
|
|
- Connect Master board PE02 to Slave Board PE02
|
|
- Connect Master board PE05 to Slave Board PE05
|
|
- Connect Master board PE06 to Slave Board PE06
|
|
- 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
|
|
|
|
|
|
*/
|