Send an ACMD41 command
CC = 0x1 ?
NO
CTO = 0x1 ?
Send an CMD1 command*
End
CTO = 0x1 ?
NO
CC = 0x1 ?
NO
NO
Is it equal to 0x1 ?
Send a CMD3 command
Send a CMD7 command
Is it equal to 0x1 ?
SD cards
A
Card type?
YES
(it is a SD card compliant
with standard 1.x)
Read the SD_STAT
register
Set SD_SYSCTL[25] SRC
bit to 0x1 and wait until it returns to 0x0
Read the SD_STAT
register
Verify the card is busy: read the
SD_RSP10[31] bit
Verify the card is busy: read the
SD_RSP10[31] bit
B
B
Send a CMD2 command to get
information on how to access
the card content
MMC cards
YES, and all cards
are not identified
NO, or all cards
are identified
Is there more than one MMC
connected to the same bus, and are
they all indentified
End
(unknown
type of card)
YES
Send an CMD55 command
YES
(It is a MMC card)
YES
(The card is not busy)
NO
(The card is busy)
YES
(It is a MMC card)
NO
(The card is busy)
YES
(The card is not busy)
*With OCR 0.
Preliminary
www.ti.com
Low-Level Programming Models
Figure 9-28. SD/SDIO Controller Card Identification and Selection - Part 2
961
SPRUGX9 – 15 April 2011
Secure Digital (SD)/—Secure Digital I/O (SDIO) Card Interface
© 2011, Texas Instruments Incorporated