Table 140. Au_Size Field; Table 141. Maximum Au Size; Table 142. Erase Size Field; Table 143. Erase Timeout Field - ST STM32F40 Series Reference Manual

Secure digital input/output interface (SDIO)
Table 140. AU_SIZE field (continued)
09h
Ah – Fh
The maximum AU size, which depends on the card capacity, is defined in
card can be set to any AU size between RU size and maximum AU size.

Table 141. Maximum AU size

Capacity
Maximum AU Size
ERASE_SIZE
This 16-bit field indicates N
value is specified by ERASE_TIMEOUT (Refer to ERASE_TIMEOUT). The host should
determine the proper number of AUs to be erased in one operation so that the host can
show the progress of the erase operation. If this field is set to 0, the erase timeout
calculation is not supported.

Table 142. Erase size field

ERASE_SIZE
0000h
0001h
0002h
0003h
---------
FFFFh
ERASE_TIMEOUT
This 6-bit field indicates T
multiple AUs are being erased as specified by ERASE_SIZE. The range of
ERASE_TIMEOUT can be defined as up to 63 seconds and the card manufacturer can
choose any combination of ERASE_SIZE and ERASE_TIMEOUT depending on the
implementation. Determining ERASE_TIMEOUT determines the ERASE_SIZE.

Table 143. Erase timeout field

ERASE_TIMEOUT
00
01
02
03
875/1422
AU_SIZE
16 MB-64 MB
512 KB
. When N
ERASE
Erase timeout calculation is not supported.
1 AU
2 AU
3 AU
---------
65535 AU
and the value indicates the erase timeout from offset when
ERASE
Erase timeout calculation is not supported.
1 [sec]
2 [sec]
3 [sec]
Doc ID 018909 Rev 4
Value definition
4 MB
Reserved
128 MB-256 MB
1 MB 2 MB
numbers of AUs are erased, the timeout
ERASE
Value definition
Value definition
RM0090
Table 141. The
512 MB 1 GB-32 GB
4 MB