Техническая Спецификация для Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK

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SAM9M10 [DATASHEET]

6355F–ATARM–12-Mar-13

After reset, the HSMCI is disabled and becomes valid after setting the MCIEN bit in the HSMCI_CR Control
Register.

The PWSEN bit saves power by dividing the HSMCI clock by 2

PWSDIV 

+ 1 when the bus is inactive.

The two bits, RDPROOF and WRPROOF in the HSMCI Mode Register (HSMCI_MR) allow stopping the HSMCI
Clock during read or write access if the internal FIFO is full. This will guarantee data integrity, not bandwidth.

All the timings for High Speed MultiMedia Card are defined in the High Speed MultiMediaCard System
Specification.

The two bus modes (open drain and push/pull) needed to process all the operations are defined in the HSMCI
command register. The HSMCI_CMDR allows a command to be carried out.

For example, to perform an ALL_SEND_CID command:

The command ALL_SEND_CID and the fields and values for the HSMCI_CMDR Control Register are described in

Note:

bcr means broadcast command with response.

The HSMCI_ARGR contains the argument field of the command.

To send a command, the user must perform the following steps:

• Fill the argument register (HSMCI_ARGR) with the command argument.

• Set the command register (HSMCI_CMDR) (see 

The command is sent immediately after writing the command register.

CMD

S

T

Content

CRC

E

Z

******

Z

S

T

Content

Z

Z

Z

ALL_SEND_CID Command Description 

CMD2

bcr

[31:0] stuff bits

R2

ALL_SEND_CID

Asks all cards to send 
their CID numbers on 
the CMD line

Fields and Values for HSMCI_CMDR Command Register 

CMDNB (command number)

2 (CMD2) 

RSPTYP (response type)

2 (R2: 136 bits response)

SPCMD (special command)

0 (not a special command)

OPCMD (open drain command)

1

MAXLAT (max latency for command to response)

0 (NID cycles ==> 5 cycles) 

TRCMD (transfer command)

0 (No transfer)

TRDIR (transfer direction)

X (available only in transfer command)

TRTYP (transfer type)

X (available only in transfer command)

IOSPCMD (SDIO special command)

0 (not a special command)