at91sam9260-cj ATMEL Corporation, at91sam9260-cj Datasheet - Page 554

• Manufacturer Part Number: at91sam9260-cj
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

Figure 35-7. SD Card Bus Connections with Two Slots
Note:
Figure 35-8. Mixing MultiMedia and SD Memory Cards with Two Slots
Note:
35.7
6221G–ATARM–31-Jan-08
When several MCI (x MCI) are embedded in a product, MCCK refers to MCIx_CK,MCCDA to MCIx_CDA, MCDAy to MCIx_DAy,
MCCDB to MCIx_CDB, MCDBy to MCIx_DBy.
When several MCI (x MCI) are embedded in a product, MCCK refers to MCIx_CK, MCCDA to MCIx_CDA, MCDAy to
MCIx_DAy, MCCDB to MCIx_CDB, MCDBy to MCIx_DBy.
MultiMedia Card Operations
MCDB0 - MCDB3
When the MCI is configured to operate with SD memory cards, the width of the data bus can be
selected in the MCI_SDCR register. Clearing the SDCBUS bit in this register means that the
width is one bit; setting it means that the width is four bits. In the case of multimedia cards, only
the data line 0 is used. The other data lines can be used as independent PIOs.
After a power-on reset, the cards are initialized by a special message-based MultiMedia Card
bus protocol. Each message is represented by one of the following tokens:
• Command: A command is a token that starts an operation. A command is sent from the host
either to a single card (addressed command) or to all connected cards (broadcast
command). A command is transferred serially on the CMD line.
MCCDA
MCCDB
MCDA0
MCCK
MCDB0 - MCDB3
MCDA0 - MCDA3
MCCDB
MCCDA
MCCK
1
2 3 4 5 6
MMC1
7
SD CARD
1
2 3 4 5 6
MMC2
SD CARD 1
SD CARD 2
7
1
2 3 4 5 6
MMC3
AT91SAM9260
7
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