SPI_FullDuplex_ComPolling_Slave Example Description

Data buffer transmission/reception between two boards via SPI using Polling mode.

   Board: NUCLEO-C031C6 (embeds a STM32C031C6 device)
   - CLK Pin: PB3 (CN9, pin 4)
   - MISO Pin: PB4 (CN9, pin 6)
   - MOSI Pin: PB5 (CN9, pin 7)

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.

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 Full-Duplex SPI transfer (16bit) is done using LL Driver functions LL_SPI_TransmitData16 and LL_SPI_ReceiveData16.

Example execution:

First step, press the User push-button (User push-button), this action initiates a Full-Duplex transfer between Master and Slave.

After end of transfer, aRxBuffer and aTxBuffer are compared through Buffercmp() in order to check buffers correctness.

STM32 board LED can be used to monitor the transfer status:

Notes

  1. You need to perform a reset on Slave board, then perform it on Master board to have the correct behaviour of this example.

  2. 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.

  3. The application need to ensure that the SysTick time base is always set to 1 millisecond to have correct HAL operation.

Keywords

Connectivity, SPI, Full-duplex, Transmission, Reception, Slave, MISO, MOSI, Polling

Directory contents

Hardware and Software environment

How to use it ?

In order to make the program work, you must do the following: