SPI communication method of nrf 52832 and SD card.

[y001]

Hello!

I am a beginner.

I am trying to communicate with the SD card with SPI using nrf 52832.(BLE Nano v2)

I am using fatfs of nRF5_SDK_15.0.0_a53641a. I am writing a program with keil.

I refer to sdcard.c to initialize the SD card, but I do not know how to use it and I not initialize it.

How do you describe it in the main program?

Thank you!

[Jakub Rzeszutko]

Hi,

Did you check an example provided in the SDK?

\sdk\nrf5\examples\peripheral\fatfs

[y001]

HI,

thank you for your reply!

nRF5_SDK_15.0.0_a53641a/examples/peripheral/fatfs  is referred to.

On the first row

#define SDC_SCK_PIN     2   ///< SDC serial clock (SCK) pin.
#define SDC_MOSI_PIN    29  ///< SDC serial data in (DI) pin.
#define SDC_MISO_PIN    30  ///< SDC serial data out (DO) pin.
#define SDC_CS_PIN      28  ///< SDC chip select (CS) pin.

If you change the pin number and use it, a file is created and added to a text file.

#define TEST_STRING "SD card example."

Will characters weitten as defined in are written ?

Are there other parts to change?

[Jakub Rzeszutko]

Example is intended to create a file: NORDIC.TXT
Within this file you shall see text "SD card example."

Update:

Some SD cards requires different pull up configuration on MISO line. You can modify it in the sdk_config.h file: NRF_SPI_DRV_MISO_PULLUP_CFG

[y001]

Thank you

I found out thea using fatfs makes it possible to write to a file, but I do not know how to put the SD card in SPI mode.

Do you know what to do?

[Jørgen Holmefjord]

The FatFS example will put the SD card in SPI mode. The card is put in SPI mode by pulling the CS/CD pin low. Please read more in footnote 3 of chapter 3.7.1 in SD Association Part1 Physical Layer Simplified Specification Ver6.00.

[y001]

I was able to execure fatfs by changing CS from HIGH to LOW!

Thank you for your cooperation!