Example explanation of SPI transaction manager

[Ree Wang]

Hi DevZone,

Regarding example: \examples\peripheral\spi_master_using_nrf_spi_mngr, can I ask several questions?

1. I want to modify this code for receive the response from SPI slave too. For configuration, is it only thing I need to do is adding miso_pin number?

.miso_pin = ARDUINO_12_PIN.

2. I want to check the Tx and Rx data, but I could not find the function nrf_drv_spi_transfer, could you please tell how this function is in the example? How can I check the tx and rx data?

Best regards

[Edvin]

Hello,

For a simple spi example with a TX and an RX buffer, I suggest that you take a look at the spi (master) and spis (slave) examples, found in SDK\examples\peripheral\...

If you need to use the spi_master_using_nrf_spi_mngr there are a couple of things you must set in order to see the data coming from the spi slave:
You must set the .miso_pin, as you describe. You will also have to set the .end_callback to something else than NULL, and pass it into nrf_spi_mngr_schedule. This is the function that will be called when the transaction is complete. 

The data is located in the 3rd input variable in NRF_SPI_MNGR_TRANSFER(...). Please see this post.

 

Best regards,

Edvin

[Edvin]

This will work if you use one buffer. If you need different buffers to different SPI slaves, you can send the pointer to the buffer through the p_user_data parameter before NRF_SPI_MNGR_TRANSFER(...).

BR,

Edvin

[Ree Wang]

Thanks. My project is for simple spi example. I was trying spi(master), but Nordic could not receive the response... The detailed issue is https://devzone.nordicsemi.com/f/nordic-q-a/32012/spi-communication-failure-between-nrf52840-preview-dk-and-arduino-uno

[Edvin]

Ok. It seems like there is some issues with the setup between the two SPI devices. I see you have received a reply on the case that you linked to. I do not have an Arduino to test on in the office, so maybe my colleague can help you in your other post. Do you have any analyzing tools, like an oscilloscope or a logic analyzer that you can check the traffic on the MISO and MOSI pins?

 

Best regards,

Edvin

[Ree Wang]

Thank you very much.

I don't have a oscilloscope or a logic analyzer. But I did a loopback test simply connect MISO and MOSI pins. The log shows the data input from MISO and output send by MOSI are the same. So I think both MISO and MOSI PINs are working well.  

Best regards