Renesas SH7781 - Manual (Page 1226)

24. Multimedia Card Interface (MMCIF)
Rev.1.00 Jan. 10, 2008 Page 1196 of 1658
REJ09B0261-0100
24.3.10 Mode Register (MODER)
MODER is an 8-bit readable/writable register that specifies the MMCIF operating mode. The
following sequence should be repeated when the MMCIF uses the multimedia card: Send a
command, wait for the end of the command sequence and the end of the data busy state, and send
a next command.
The series of operations from command sending, command response reception, data
transmission/reception, and data response reception is called as the command sequence. The
command sequence starts from sending a command by setting the CMDSTART bit in CMDSTRT
to 1, and ends when all necessary data transmission/reception and response reception have been
completed. The multimedia card supports the data busy state such that only the specific command
is accepted to write/erase data to/from the flash memory in the card during command sequence
execution and after command sequence execution has ended. The data busy state is indicated by a
low level output from the card side to the MMCDAT pin.
Bit:
Initial value:
R/W:
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
R
MODE
R R R R R R R/W
⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
Bit Bit Name
Initial
Value R/W Description
7 to 1 — All 0 R Reserved
These bits are always read as 0. The write value should
always be 0.
0 MODE 0 R/W Operating Mode
Specifies the MMCIF operating mode.
0: Operates in MMC mode
1: Setting prohibited