Specifications

©Copyright 2001-2013 SD Group (Panasonic, SanDisk, Toshiba) and SD Card Association
Physical Layer Simplified Specification Version 4.10
89
• AU_SIZE
This 4-bit field indicates AU Size and the value can be selected from 16 KB.
AU_SIZE
Value Definition
0h
Not Defined
1h
16 KB
2h
32 KB
3h
64 KB
4h
128 KB
5h
256 KB
6h
512 KB
7h
1 MB
8h
2 MB
9h
4 MB
Ah
8 MB
Bh
12 MB
Ch
16 MB
Dh
24 MB
Eh
32 MB
Fh
64 MB
Table 4-46: AU_SIZE Field
The maximum AU size, depends on the card capacity, is defined in Table 4-47. The card can set any AU
size specified in Table 4-46 that is less than or equal to the maximum AU size. The card should set
smaller AU size as much as possible.
Table 4-47: Maximum AU size
Application Notes:
The host should determine host buffer size based on total busy time of 4MB and the
card supported
class. The host can treat multiple AUs combined as one unit.
• ERASE_SIZE
This 16-bit field indicates N
ERASE
. When N
ERASE
numbers of AUs are erased, the timeout value is
specified by ERASE_TIMEOUT (Refer to ERASE_TIMEOUT). The host should determine proper
number of AUs to be erased in one operation so that the host can indicate progress of erase operation.
If this field is set to 0, the erase timeout calculation is not supported.
ERASE_SIZE
Value Definition
0000h
Erase Time-out Calculation is not supported.
0001h
1 AU
0002
2 AU
0003
3 AU
.......
.......
FFFFh
65535 AU
Table 4-48: Erase Size Field
Card Capacity
up to 64MB
up to 256MB
up to 512MB
up to 32GB
up to 2TB
Maximum AU Size
512 KB
1 MB
2 MB
4 MB
1
64MB