Inky Frame: Sensible limit on SDCard speed.
Going any faster will result in corruption- this showed up as visible lines of distortion down decoded JPEG files.
#define CT_BLOCK 0x08 /* Block addressing */
#define CLK_SLOW (100 * KHZ)
-#define CLK_FAST (50 * MHZ)
+#define CLK_FAST (30 * MHZ)
static volatile
DSTATUS Stat = STA_NOINIT; /* Physical drive status */
