151 lines
8.3 KiB
Plaintext
151 lines
8.3 KiB
Plaintext
/**
|
|
@page I2C_WakeUpFromStop I2C Two Boards Communication IT Example on Stop Mode
|
|
|
|
@verbatim
|
|
******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
|
|
* @file I2C/I2C_WakeUpFromStop/readme.txt
|
|
* @author MCD Application Team
|
|
* @brief Description of the Wake Up from Stop mode example
|
|
******************************************************************************
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without modification,
|
|
* are permitted provided that the following conditions are met:
|
|
* 1. Redistributions of source code must retain the above copyright notice,
|
|
* this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
* this list of conditions and the following disclaimer in the documentation
|
|
* and/or other materials provided with the distribution.
|
|
* 3. Neither the name of STMicroelectronics nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
|
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
******************************************************************************
|
|
@endverbatim
|
|
|
|
@par Example Description
|
|
|
|
This example describes how to perform I2C data buffer transmission/reception between
|
|
two boards using an interrupt when the device is in STOP mode.
|
|
|
|
_________________________ _________________________
|
|
| ______________| |______________ |
|
|
| | I2C1 | | I2C1| |
|
|
| | | | | |
|
|
| | SCL(PB6)|______________________|(PB6)SCL | |
|
|
| | | | | |
|
|
| | | | | |
|
|
| | | | | |
|
|
| | SDA(PB7)|______________________|(PB7)SDA | |
|
|
| | | | | |
|
|
| |______________| |______________| |
|
|
| __ | | __ |
|
|
| |__| | | |__| |
|
|
| USER GND|______________________|GND USER |
|
|
| | | |
|
|
|_STM32F072B_DISCOVERY____| |_STM32F072B_DISCOVERY____|
|
|
|
|
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 48 MHz. When The system is wakeup from stop mode,
|
|
system clock is 8 Mhz. The I2C peripheral is directly clocked by HSI.
|
|
|
|
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 and NVIC). You may update this function to change I2C configuration.
|
|
|
|
The I2C communication is then initiated.
|
|
The project is splitted in two parts the Master Board and the Slave Board
|
|
- Master Board
|
|
The HAL_I2C_Master_Receive_IT() and the HAL_I2C_Master_Transmit_IT() functions
|
|
allow respectively the reception and the transmission of a predefined data buffer
|
|
in Master mode using interrupt.
|
|
- Slave Board
|
|
The HAL_I2C_Slave_Receive_IT() and the HAL_I2C_Slave_Transmit_IT() functions
|
|
allow respectively the reception and the transmission of a predefined data buffer
|
|
in Slave mode using interrupt.
|
|
The user can choose between Master and Slave through "#define MASTER_BOARD"
|
|
in the "main.c" file:
|
|
- Uncomment "#define MASTER_BOARD" to select Master board.
|
|
- Comment "#define MASTER_BOARD" to select Slave board.
|
|
|
|
For this example the aTxBuffer is predefined and the aRxBuffer size is same as aTxBuffer.
|
|
|
|
In a first step after the user presses the User push-button on the Master Board, I2C Master
|
|
starts the communication by sending aTxBuffer through HAL_I2C_Master_Transmit_IT() to
|
|
I2C Slave which wakes up from stop mode and receives aRxBuffer through HAL_I2C_Slave_Receive_IT().
|
|
The second step starts when the user presses the User push-button on the Master Board,
|
|
the I2C Slave after wake up from stop mode at address match, sends aTxBuffer through HAL_I2C_Slave_Transmit_IT()
|
|
to the I2C Master which receives aRxBuffer through HAL_I2C_Master_Receive_IT().
|
|
|
|
The end of this two steps are monitored through the HAL_I2C_GetState() function
|
|
result.
|
|
Finally, aTxBuffer and aRxBuffer are compared through Buffercmp() in order to
|
|
check buffers correctness.
|
|
|
|
STM32F072B-Discovery RevC's LEDs can be used to monitor the transfer status on the Slave Board :
|
|
- LED_GREEN is ON when the Transmission process is complete.
|
|
- LED_GREEN is OFF when the Reception process is complete.
|
|
- LED_RED is ON when there is an error in transmission/reception process.
|
|
- LED_BLUE is ON when Slave enters stop mode.
|
|
- LED_BLUE is OFF when Slave wakes up from stop.
|
|
|
|
@note I2Cx instance used and associated resources can be updated in "main.h"
|
|
file depending hardware configuration used.
|
|
|
|
@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 need to ensure that the SysTick time base is always set to 1 millisecond
|
|
to have correct HAL operation.
|
|
|
|
@par Directory contents
|
|
|
|
- I2C/I2C_WakeUpFromStop/Inc/stm32f0xx_hal_conf.h HAL configuration file
|
|
- I2C/I2C_WakeUpFromStop/Inc/stm32f0xx_it.h I2C interrupt handlers header file
|
|
- I2C/I2C_WakeUpFromStop/Inc/main.h Header for main.c module
|
|
- I2C/I2C_WakeUpFromStop/Src/stm32f0xx_it.c I2C interrupt handlers
|
|
- I2C/I2C_WakeUpFromStop/Src/main.c Main program
|
|
- I2C/I2C_WakeUpFromStop/Src/system_stm32f0xx.c STM32F0xx system source file
|
|
- I2C/I2C_WakeUpFromStop/Src/stm32f0xx_hal_msp.c HAL MSP file
|
|
|
|
|
|
@par Hardware and Software environment
|
|
|
|
- This example runs on STM32F072RB devices.
|
|
|
|
- This example has been tested with STM32F072B-Discovery RevC board and can be
|
|
easily tailored to any other supported device and development board.
|
|
|
|
-STM32F072B-Discovery RevC Set-up
|
|
- Connect Master board PB6 to Slave Board PB6
|
|
- Connect Master board PB7 to Slave Board PB7
|
|
- 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
|
|
|
|
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
|
|
*/
|