Did you try my suggestions on SparkFun?
I.e try manually mounting by:
mount -t vfat /dev/mmcblk1 /mnt/mmc
If the above mount command doesn't work try:
mount -t vfat /dev/mmcblk1p1 /mnt/mmc
Also what is your output from:
dmesg -T | grep mmc1
I managed to get a Sandisk Ultra 16GB SDHC UHC-1 working by this method. Although not technically a class 10 it is the UHC equivalent.
P.S How do I format code in tags?
g.gregory, thank you for the suggestions on the sparkfun thread, I did try them. The problem is that /dev/mmcblk1 and /dev/mmcblk1p1 do not exist. I do not know if they are dynamically created when the card is recognized of one needs to create them with mknod. With no /dev file, the mount command fails.
The output from dmesg is actually the error message in the the title of this thread:
mmc1: error -110 whilst initialising SD card
I have verified that this message appears each time a card is inserted.
I have ordered a class -4 card on the suggestion of Kevin above, but have not yet received it. The only other card that I have is a 64Gb class 10, but as I understood it 32 is the limit. I might just pop it in there to see what happens (not expecting it to work).
If I have success with either, I will report back the result.