Datasheet

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Pin Number Name Type
(1)
Description HSMCI Pin Name
(2)
(Slot z)
6 VSS2 S Supply voltage ground VSS
7 DAT[0] I/O/PP Data line Bit 0 MCDz0
8 DAT[1] I/O/PP Data line Bit 1 or Interrupt MCDz1
9 DAT[2] I/O/PP Data line Bit 2 MCDz2
Note:
1.
I: input, O: output, PP: Push Pull, OD: Open Drain.
2. When several HSMCI (x HSMCI) are embedded in a product, MCCK refers to HSMCIx_CK, MCCDA to
HSMCIx_CDA, MCDAy to HSMCIx_DAy.
Figure 40-6. SD Card Bus Connections with One Slot
2 3 4 5 61 7
MCDA0 - MCDA3
MCCDA
MCCK
8
SD CARD
9
Note:
When several HSMCI (x HSMCI) are embedded in a product, MCCK refers to HSMCIx_CK, MCCDA to
HSMCIx_CDA MCDAy to HSMCIx_DAy.
When the HSMCI is configured to operate with SD memory cards, the width of the data bus can be selected in the
HSMCI_SDCR. 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 High Speed MultiMedia cards, only the data line 0 is used. The other data lines can
be used as independent PIOs.
40.8 High-Speed Multimedia Card Operations
After a power-on reset, the cards are initialized by a special message-based High-Speed 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.
• Response—A response is a token which is sent from an addressed card or (synchronously) from all connected
cards to the host as an answer to a previously received command. A response is transferred serially on the
CMD line.
• Data—Data can be transferred from the card to the host or vice versa. Data is transferred via the data line.
Card addressing is implemented using a session address assigned during the initialization phase by the bus
controller to all currently connected cards. Their unique CID number identifies individual cards.
The structure of commands, responses and data blocks is described in the High-Speed Multimedia Card System
Specification. See Table 40-4 for additional information.
High-Speed Multimedia Card bus data transfers are composed of these tokens.
There are different types of operations. Addressed operations always contain a command and a response token. In
addition, some operations have a data token; the others transfer their information directly within the command or
response structure. In this case, no data token is present in an operation. The bits on the DAT and the CMD lines are
transferred synchronous to the clock HSMCI clock.
Two types of data transfer commands are defined:
• Sequential commands—These commands initiate a continuous data stream. They are terminated only when a
stop command follows on the CMD line. This mode reduces the command overhead to an absolute minimum.
SAM E70/S70/V70/V71 Family
High-Speed Multimedia Card Interface (HSMCI)
©
2019 Microchip Technology Inc.
Datasheet
DS60001527D-page 930