Fatfs example does not work with every sd card?

Question

Hi, I am working on application where I need to store some bigger files. I chose to use sdcard, but I get weird behaviour. Some sd cards, this looks like totaly random ones are working and other are not with fatfs on nrf52. I was trying few cards with fatfs example from SDK and one was working while all other seems to hang up at disk_initialization: 0> app: FATFS example. 0> app: Initializing disk 0 (SDC)... 0> spi: Init 0> spi: Function: nrf_drv_spi_init, error code: NRF_SUCCESS. 0> spi: Transfer tx_len:1, rx_len:10. 0> spi: Function: spim_xfer, error code: NRF_SUCCESS. 0> spi: Transfer completed rx_len:10. 0> spi: Transfer tx_len:6, rx_len:15. 0> spi: Function: spim_xfer, error code: NRF_SUCCESS. 0> spi: Transfer completed rx_len:15. 0> spi: Transfer tx_len:6, rx_len:15. I tried making changes as suggested here: https://devzone.nordicsemi.com/f/nordic-q-a/25951/sd-card-example-not-working-fine but it wont help. I can work with that few are not working but it looks like most of them is not working. Is there recommended sdcard size/type/manufacturer to be used with nrf52? Regards, Michał

hmolesworth · Accepted Answer

The default SPI settings use standard drive for the SCK and MOSI pins; it's perhaps worth checking whether they simply need to be set to high drive (typically required only at higher clock frequencies). Offhand I don't know whether the FATFS example already does that, but most examples do not. Here's an example, must be set after SPI initialise (or change within SPI init): 
 nrf_gpio_cfg(SCK_PIN,
 NRF_GPIO_PIN_DIR_OUTPUT,
 NRF_GPIO_PIN_INPUT_DISCONNECT,
 NRF_GPIO_PIN_NOPULL,
 NRF_GPIO_PIN_H0H1, // Require High Drive low/high level
 NRF_GPIO_PIN_NOSENSE);

Fatfs example does not work with every sd card?

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