[SPI Loopback Test] Rx is not working as expected, receiving 3 bytes(only) repeatedly

[Hardik Prajapati]

Posted on July 13, 2018 at 08:11

Hello ST Team,

I am working on STM32091C-EVAL board, and I need to work on SPI so loopback test preferred. But I am facing some issue while receiving the data, receiving 3 consecutive bytes(except 1st byte) repeatedly.

What I have done:

- Connect MISO and MOSI to test loopback test.

- Configure SPI in Master mode, also with many parameters what it needed to register the handler.

- I am sending static data and trying to receive it with that static length.

What I am facing:

- If I send 'abcdefghi', then I would receive 'bcdbcdbcd', I don't know why the first character is missing and why this is so repeatedly?

Note:

- By 'HAL_SPI_TransmitReceive_IT' API I am not facing any issue in Tx and Rx, but this persists only in separate APIs for Tx and Rx('HAL_SPI_Transmit_IT' and 'HAL_SPI_Receive_IT'), 

However, I am able to Tx the data using '

HAL_SPI_Transmit_IT' API but not able to receive proper data using '

HAL_SPI_Receive_IT' (As described above).

Let me know if you need any more information.

Any suggestions are welcome.

Thanks in advance,

Hardik Prajapati

#hal-spi #spi-communication #spi-write-and-read #spi_rx #stm32-spi-interrupts #spi