SPI STM32H743 function problem

[JovanCicic021]

Hi, I have problem with my SPI peripheral. For generate inicial code I used STM32 Cube IDE Version 6.14.1, and programming IDE STM32 Cube IDE Version 1.18.1.

Description of problem:

1.I want simple to check loop with transmit and receive data, but when I do that I always have 0 or 255 in receive register. I tried the same thing with UART, and it works.

2.On SCK I don't have clock, I try with oscilloscope to see but nothing.

In attachment I leave full project and video, please can someone check and say me some advice.

[TDK · Accepted solution]

> 1.I want simple to check loop with transmit and receive data, but when I do that I always have 0 or 255 in receive register. I tried the same thing with UART, and it works.

> //HAL_UART_Transmit(&huart4, &b, 1, 100);
> //HAL_UART_Receive(&huart4, &d, 1, 100);
> HAL_SPI_Transmit(&hspi4, &b, 1, 100);
> HAL_SPI_Receive(&hspi4, &d, 1, 100);

SPI is not asynchronous like UART. Data is sent and received at the same time. To send and receive one byte:

HAL_SPI_TransmitReceive(&hspi4, &b, &d, 1, 100);

If MOSI is connected to MISO, then the received data (d) will match the sent data (b).

> 2.On SCK I don't have clock, I try with oscilloscope to see but nothing.

> GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;

Set SPI pin speed to very high, or reduce clock rate.,

[JovanCicic021]

Thank you very much, first question solve, and in attachment video how it is working (SPI_STM32H743).

I didn't use GPIO A7 for synchronize periphery, I used SCK pin from SPI. I try to see physically external clock, how synchronized slave.

With this GPIO A7 I selected slave, and that worked.

I am trying to read MPU 9250 gyroscope, but I can't. And I am not sure witch parth not working.