How to transmit data bytes from an I2C master device using polling mode to an I2C slave device using interrupt mode. The peripheral is initialized with LL unitary service functions to optimize for performance and size.
This example guides you through the different configuration steps by mean of LL API to configure GPIO and I2C peripherals using only one NUCLEO-C071RB.
The user can disable internal pull-up by opening ioc file.
For that, user can follow the procedure :
The example is updated with no pull on each pin used for I2C communication
I2C1 Peripheral is configured in Slave mode with EXTI (Clock 400Khz, Own address 7-bit enabled). I2C2 Peripheral is configured in Master mode (Clock 400Khz). GPIO associated to User push-button is linked with EXTI.
LED1 blinks quickly to wait for user-button press.
Example execution:
Press the User push-button to initiate a write request by Master through Handle_I2C_Master() routine. This action will generate an I2C start condition with the Slave address and a write bit condition. When address Slave match code is received on I2C1, an ADDR interrupt occurs. I2C1 IRQ Handler routine is then checking Address Match Code and direction Write. This will allow Slave to enter in receiver mode and then acknowledge Master to send the bytes. When acknowledge is received on I2C2, a TXIS event occurs. This will allow Master to transmit a byte to the Slave. Each time a byte is received on I2C1 (Slave), an RXNE interrupt occurs until a STOP condition. And so each time the Slave acknowledge the byte received a TXIS event occurs on Master side. Master auto-generate a Stop condition when size of data to transmit is achieved.
The STOP condition generate a STOP interrupt and initiate the end of reception on Slave side. I2C1 IRQ handler and Handle_I2C_Master() routine are then clearing the STOP flag in both side.
LED1 is On if data are well received.
In case of errors, LED1 is blinking slowly (1s).
Connectivity, Communication, I2C, Interrupt, Polling, Master, Slave, Transmission, Reception, Fast mode
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Inc/stm32c0xx_it.h Interrupt handlers header file
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Inc/main.h Header for main.c module
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Inc/stm32_assert.h Template file to include assert_failed function
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Src/stm32c0xx_it.c Interrupt handlers
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Src/main.c Main program
- I2C/I2C_OneBoard_Communication_PollingAndIT_Init/Src/system_stm32c0xx.c STM32C0xx system source file
This example runs on STM32C071RBTx devices.
This example has been tested with NUCLEO-C071RB board and can be easily tailored to any other supported device and development board.
NUCLEO-C071RB Set-up
Launch the program.
Press User push-button to initiate a write request by Master then Slave receive bytes.
In order to make the program work, you must do the following :