FATFS example doesn't work ...

[eyalasko]

Hi , 

I'm trying to evaluate the FATFS example and unfortunately the statement disk_initialize(0) in main.c fails.

I'm using PCA10040, SDK 15.1, and switched between several SD cards (2-16GB), wires set and SD socket breakout boards without any success...

The only change in the example code I did is setting CS to pin 19 (though I also tried to leave it 22) when using Sparkfun's micro SD shield.

I've single stepped through the code to the lowest level: disk_initialize(0) @main.c >> nrf_blk_dev_init() @nrf_block_dev.h >> block_dev_sdc_init() @nrf_block_dev_sdc.c  >> app_sdc_init() @app_sdcard.c >> which calls nrf_drv_spi_transfer() with CS_DEASSERTed to generate 80 SCLK pulses (as the comment in the code says)

I've set a breakpoint in the callback sdc_handler() @nrf_block_dev_sdc.c and noticed that event->result = 0x04 SDC_ERROR_COMMUNICATION (in case SDC_EVT_INIT: block)

What can cause this initialization failure?

Thanks

[eyalasko]

Another observation - 

in main.c disk_initialize(0) is recalled again (3 times) if it failed.

On calls 2 & 3 the nested calls described above terminates at block_dev_sdc_init() @nrf_block_dev_sdc.c with return code NRF_ERROR_BUSY...

[eyalasko]

I've found the answer here