Renesas SH7781 User Manual

Page 1242

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24. Multimedia Card Interface (MMCIF)

Rev.1.00 Jan. 10, 2008 Page 1212 of 1658
REJ09B0261-0100

Yes

Start of command sequence

Set command data in CMDR0 to CMDR4

Set command type in CMDTYR

Set command response type in RSPTYR

Set the CMDSTART bit in CMDSTRT to 1

(CMDI) interrupt detected?

End of command sequence

No

Figure 24.4 Example of Operational Flow for Commands

Not Requiring Command Response

(4)

Operation of Commands without Data Transfer

Broadcast, relative address, and flash memory operation commands include a number of
commands that do not include data transfer. Such commands execute the desired data transfer
using command arguments and command responses. For a command that is related to time-
consuming processing such as flash memory write/erase, the card indicates the data busy state via
the MMCDAT.

Figures 24.5 and 24.6 show examples of the command sequence for commands without data
transfer.

Figure 24.7 shows the operational flow for commands without data transfer.

• Make settings to issue the command.
• Set the CMDSTART bit in CMDSTRT to 1 to start command transmission.

Command transmission completion can be confirmed by the command transmit end interrupt
(CMDI).

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