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/**
@page I2C_OneBoard_ComSlave7_10bits_IT I2C One Board Communication Slave 10-Bit
then Slave 7-Bit IT example
@verbatim
******************** (C) COPYRIGHT 2019 STMicroelectronics *******************
* @file Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/readme.txt
* @author MCD Application Team
* @brief Description of the I2C One Board Master Communication with
* a Slave 10-Bit address then a Slave 7-Bit address example.
******************************************************************************
*
* Copyright (c) 2019-2021 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 perform I2C data buffer transmission/reception between
one master and two slaves with different address sizes (7-bit or 10-bit). This example
uses the STM32WBxx I2C HAL and LL API (LL API usage for performance improvement)
and an interrupt.
Board: P-NUCLEO-WB55 (embeds a STM32WB55RG device)
SCL MASTER Pin:PC0 (CN7, pin28)
SDA MASTER Pin:PC1 (CN7, pin30)
SCL SLAVE Pin: PB8 (CN10, pin3)
SDA SLAVE Pin: PB9 (CN10, pin5)
____________________________________________
| ____________ ____________ |
| | I2C3 | |I2C1 | |
| | | | | |
| | SCL_MASTER|________|SCL_SLAVE | |
| | | | | |
| | | | | |
| | SDA_MASTER|________|SDA_SLAVE | |
| |____________| |____________| |
| __ |
| |__| |
| USER |
| |
|____________________________________________|
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 16 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 and NVIC). You may update this function to change I2C configuration.
The user can disable internal pull-up by opening ioc file.
For that, user can follow the procedure :
1- Double click on the I2C_OneBoard_ComSlave7_10bits_IT.ioc file
2- When CUBEMX tool is opened, select System Core category
3- Then in the configuration of GPIO/I2C3, change Pull-up to No pull-up and no pull-down for the both pins
4- Same action in the configuration of GPIO/I2C1, change Pull-up to No pull-up and no pull-down for the both pins
5- Last step, generate new code thanks to button "GENERATE CODE"
The example is updated with no pull on each pin used for I2C communication
For this example two buffers are used
- aTxBuffer buffer contains the data to be transmitted
- aRxBuffer buffer is used to save the received data
Note that both buffers have same size
Example execution:
First step, press the User push-button (SW1), this action initiates a reception process (aRxBuffer) for
I2C Slave1 or Slave2 address through HAL_I2C_Slave_Receive_IT().
Then I2C Master starts the communication by sending aTxBuffer through HAL_I2C_Master_Transmit_IT()
for Slave1 (10-Bit address).
The end of this step is monitored through the HAL_I2C_GetState() function
result.
Finally, aTxBuffer and aRxBuffer are compared through Buffercmp() in order to
check buffers correctness.
Toggle LED2 when data is received correctly, otherwise LED3 is ON and communication is stopped (using infinite loop)
Second step, press the User push-button (SW1), this action initiates a transmission process (aTxBuffer) for
I2C Slave1 or Slave2 address through HAL_I2C_Slave_Transmit_IT().
Then I2C Master starts the communication by receiving aRxBuffer through HAL_I2C_Master_Transmit_IT()
from Slave2 (7-Bit address).
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.
Toggle LED2 when data is received correctly, otherwise LED3 is ON and communication is stopped (using infinite loop)
@note In Master side, only Acknowledge failure error is handled. When this error
occurs Master restart the current operation until Slave acknowledges it's
address.
@note I2C3 and I2C1 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 Keywords
Connectivity, Communication, I2C, SDA, SCL, Slave, 7 bits, 10 Bits, Interrupt, Transmission, Reception, Acknowledge
@par Directory contents
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Inc/stm32wbxx_hal_conf.h HAL configuration file
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Inc/stm32wbxx_it.h I2C interrupt handlers header file
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Inc/main.h Header for main.c module
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Src/stm32wbxx_it.c I2C interrupt handlers
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Src/main.c Main program
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Src/system_stm32wbxx.c STM32WBxx system source file
- Examples_MIX/I2C/I2C_OneBoard_ComSlave7_10bits_IT/Src/stm32wbxx_hal_msp.c HAL MSP file
@par Hardware and Software environment
- This example runs on STM32WB55RG devices.
- This example has been tested with P-NUCLEO-WB55 board and can be
easily tailored to any other supported device and development board.
-P-NUCLEO-WB55 Set-up
- Connect GPIOs connected to I2C1 SCL/SDA (PB8 and PB9)
to respectively SCL and SDA pins of I2C3 (PC0 and PC1).
- I2C1_SCL PB8(CN10, pin3) : connected to I2C3_SCL PC0(CN7, pin28)
- I2C1_SDA PB9(CN10, pin5) : connected to I2C3_SDA PC1(CN7, pin30)
- Launch the program.
- Press User push-button (SW1) to initiate a write request by Master
then Slave1 (10-Bit address) receive a Buffer. LED2 Toggle when data is received correctly.
- Press again User push-button (SW1) to initiate a read request by Master
then Slave2 (7-Bit address) Transmit a Buffer. LED2 Toggle when data is received correctly.
@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
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
*/
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