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 MMCi.MMCHS_STAT
register
Set MMCi.MMCHS_SYSCTL[25] SRC
bit to 0x1 and wait until it returns to 0x0
Read the MMCi.MMCHS_STAT
register
Verify the card is busy: read the
MMCi.MMCHS_RSP19[31] bit
Verify the card is busy: read the
MMCi.MMCHS_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)
108-031
*With OCR 0.
In case of a CMD1 with OCR=0, a second CMD1 must be sent to the card with the "negociated" voltage.
Public Version
www.ti.com
MMC/SD/SDIO Basic Programming Model
Figure 24-36. MMC/SD/SDIO Controller Card Identification and Selection - Part 2
24.5.2.2 Read/Write Transfer Flow in DMA Mode With Interrupt
describes the read and write protocol in DMA mode with interrupt signaling. See
,
SDMA, for more information on the DMA settings.
3401
SWPU177N – December 2009 – Revised November 2010
MMC/SD/SDIO Card Interface
Copyright © 2009–2010, Texas Instruments Incorporated