Unable to get FatFs example working nRF52840 SDK14.2

[SRose]

I am unable to get the FatFs example working for my nRF52840 dev kit board using the latest SDK14.2. I have determined this is related to the type of SD Card that is inserted. Only 1 out of the 4 I have work...

SanDisk 2GB formatted Fat16 - Doesn't work

8GB / Fat32 - Doesn't work

32GB / Fat32 - Works

64GB / ExFat - Doesn't work

Anyone have ideas on what SDCards/Formats work and do not work?

Thanks

[slayer49]

Hi, 

I had the same issue.   My card required a pullup on MISO pin in order to get the example working.

Check sdk_config.h for this section:

// <o> NRF_SPI_DRV_MISO_PULLUP_CFG  - MISO PIN pull-up configuration.
 
// <0=> NRF_GPIO_PIN_NOPULL 
// <1=> NRF_GPIO_PIN_PULLDOWN 
// <3=> NRF_GPIO_PIN_PULLUP 

#ifndef NRF_SPI_DRV_MISO_PULLUP_CFG
#define NRF_SPI_DRV_MISO_PULLUP_CFG 3
#endif

[SRose]

Correct, my card slot also required a pull up.  I had to switch from SDKv14.0 to 14.2 to fix this.  Yes, but there is a type-o in the header.  The value should be 2, not 3.