ERROR: Could not open file : DISK_ERR

I had the following config:

  'SD' :  { 'pin_cs' :  'A8',
            'pin_di' :  'B15',
            'pin_do' :  'B14',
            'pin_clk' :  'B13' }

The platform_config.h defines are looking good as well:

#define SD_CS_PIN 8/* A8 /
#define SD_DI_PIN 30/ B15 /
#define SD_DO_PIN 29/ B14 /
#define SD_CLK_PIN 28/ B13 */
#define SD_SPI EV_SPI2