n516 # mmcinfo
Device: JZ_MMC
Manufacturer ID: 41
OEM: 3432
Name: SD1GB
Tran Speed: 25000000
Rd Block Len: 512
SD version 2.0
High Capacity: No
Capacity: 962MiB
Bus Width: 4-bit
n516 # fatls mmc 0
Data transfer error: -19
block read failed: -19
No Fat FS detected