143 lines
6.9 KiB
Plaintext
143 lines
6.9 KiB
Plaintext
/**
|
|
@page I2C_TwoBoards_ComPolling I2C Two Boards Communication Polling example
|
|
|
|
@verbatim
|
|
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
|
|
* @file I2C/I2C_TwoBoards_ComPolling/readme.txt
|
|
* @author MCD Application Team
|
|
* @brief Description of the I2C Two Boards Communication 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
|
|
|
|
How to handle I2C data buffer transmission/reception between two boards,
|
|
in polling mode.
|
|
|
|
_________________________ _________________________
|
|
| ______________| |______________ |
|
|
| | I2C1 | | I2C1| |
|
|
| | | | | |
|
|
| | SCL(PB6)|______________________|(PB6)SCL | |
|
|
| | | | | |
|
|
| | | | | |
|
|
| | | | | |
|
|
| | SDA(PB9)|______________________|(PB9)SDA | |
|
|
| | | | | |
|
|
| |______________| |______________| |
|
|
| __ | | __ |
|
|
| |__| | | |__| |
|
|
| USER | | USER |
|
|
| GND|______________________|GND |
|
|
|_STM32F4 ________________| |_________________STM32F4_|
|
|
|
|
The communication is done with 2 Boards through I2C.
|
|
|
|
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 100 MHz.
|
|
|
|
The I2C peripheral configuration is ensured by the HAL_I2C_Init() function.
|
|
This later is calling the HAL_I2C_MspInit()function which core is implementing
|
|
the configuration of the needed I2C resources according to the used hardware (CLOCK &
|
|
GPIO). You may update this function to change I2C configuration.
|
|
|
|
The I2C communication is then initiated.
|
|
The project is split in two parts the Master Board and the Slave Board
|
|
- Master Board
|
|
The HAL_I2C_Master_Receive() and the HAL_I2C_Master_Transmit() functions
|
|
allow respectively the reception and the transmission of a predefined data buffer
|
|
in Master mode.
|
|
- Slave Board
|
|
The HAL_I2C_Slave_Receive() and the HAL_I2C_Slave_Transmit() functions
|
|
allow respectively the reception and the transmission of a predefined data buffer
|
|
in Slave 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 Button on the Master Board, I2C Master
|
|
starts the communication by sending aTxBuffer through HAL_I2C_Master_Transmit() to
|
|
I2C Slave which receives aRxBuffer through HAL_I2C_Slave_Receive().
|
|
The second step starts when the user press the User Button on the Master Board,
|
|
the I2C Slave sends aTxBuffer through HAL_I2C_Slave_Transmit()
|
|
to the I2C Master which receives aRxBuffer through HAL_I2C_Master_Receive().
|
|
The end of this two steps are monitored through the HAL_I2C_GetState() function
|
|
result.
|
|
Finally, aRxBuffer and aRxBuffer are compared through Buffercmp() in order to
|
|
check buffers correctness.
|
|
|
|
STM32 Nucleo boards LED can be used to monitor the transfer status:
|
|
- LED2 is ON when the transmission process is complete.
|
|
- LED2 is ON when the reception process is complete.
|
|
- LED2 toggles when there is an error in transmission/reception process.
|
|
|
|
@note I2Cx instance used and associated resources can be updated in "main.h"
|
|
file depending hardware configuration used.
|
|
|
|
@note Timeout is set to 10 Seconds which means that if no communication occurs
|
|
during 10 Seconds, a Timeout Error will be generated.
|
|
|
|
@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, Communication, I2C, Polling, Master, Slave, Transmission, Reception, Fast mode plus
|
|
|
|
@par Directory contents
|
|
|
|
- I2C/I2C_TwoBoards_ComPolling/Inc/stm32f4xx_hal_conf.h HAL configuration file
|
|
- I2C/I2C_TwoBoards_ComPolling/Inc/stm32f4xx_it.h Interrupt handlers header file
|
|
- I2C/I2C_TwoBoards_ComPolling/Inc/main.h Main program header file
|
|
- I2C/I2C_TwoBoards_ComPolling/Src/stm32f4xx_it.c Interrupt handlers
|
|
- I2C/I2C_TwoBoards_ComPolling/Src/main.c Main program
|
|
- I2C/I2C_TwoBoards_ComPolling/Src/system_stm32f4xx.c STM32F4xx system clock configuration file
|
|
- I2C/I2C_TwoBoards_ComPolling/Src/stm32f4xx_hal_msp.c HAL MSP module
|
|
|
|
|
|
@par Hardware and Software environment
|
|
|
|
- This example runs on STM32F410xx devices.
|
|
|
|
- This example has been tested with STM32F4xx-Nucleo RevC board and can be
|
|
easily tailored to any other supported device and development board.
|
|
|
|
- STM32F4xx-Nucleo Set-up
|
|
- Connect Master board PB6 to Slave Board PB6 (PB6 is connected to pin 17 in connector CN10)
|
|
- Connect Master board PB9 to Slave Board PB9 (PB9 is connected to pin 5 in connector CN10)
|
|
- 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
|
|
|
|
|
|
*/
|