Sd Status Register; Table 192. Sd Status - ST STM32F423 Reference Manual

Secure digital input/output interface (SDIO)
31.4.12

SD status register

The SD status contains status bits that are related to the SD memory card proprietary
features and may be used for future application-specific usage. The size of the SD Status is
one data block of 512 bits. The contents of this register are transmitted to the SDIO card
host if ACMD13 is sent (CMD55 followed with CMD13). ACMD13 can be sent to a card in
transfer state only (card is selected).
Table 192
fields in the table are abbreviated as follows:
Type:
•
E: error bit
•
S: status bit
•
R: detected and set for the actual command response
•
X: detected and set during command execution. The SDIO card Host must poll the card
by issuing the status command to read these bits
Clear condition:
•
A: according to the card current state
•
B: always related to the previous command. Reception of a valid command clears it
(with a delay of one command)
•
C: clear by read
Bits Identifier
511: 510 DAT_BUS_WIDTH S R
509 SECURED_MODE S R
508: 496 Reserved
495: 480 SD_CARD_TYPE
SIZE_OF_PROTE
479: 448
CT ED_AREA
447: 440 SPEED_CLASS
1054/1324
defines the different entries of the SD status register. The type and clear condition

Table 192. SD status

Type
'00'= 1 (default)
'01'= reserved
'10'= 4 bit width
'11'= reserved
'0'= Not in the mode
'1'= In Secured Mode
'00xxh'= SD Memory Cards as
defined in Physical Spec Ver1.01-
2.00 ('x'= don't care). The
S R following cards are currently
defined:
'0000'= Regular SD RD/WR Card.
'0001'= SD ROM Card
Size of protected area (See
S R
below)
Speed Class of the card (See
S R
below)
Value
RM0430 Rev 8
Description
Shows the currently defined
databus width that was
defined by
SET_BUS_WIDTH
command
Card is in Secured Mode of
operation (refer to the "SD
Security Specification").
In the future, the 8 LSBs will
be used to define different
variations of an SD memory
card (each bit will define
different SD types). The 8
MSBs will be used to define
SD Cards that do not comply
with current SD physical
layer specification.
(See below)
(See below)
RM0430
Clear
condition
A
A
A
A
A