Intel® PXA255 Processor Developer’s Manual
15-3
MultiMediaCard Controller
the bidirectional MMDAT signal. A typical MMC mode command timing diagram with and
without a response is shown in
Figure 15-2
while
Figure 15-3
shows a typical MMC mode timing
diagram for a sequential read or write
.
In SPI mode, not all commands are available. The available commands have both a command and
response token. The MMCMD and MMDAT signals are no longer bidirectional in SPI mode. The
MMCMD is an output and the MMDAT is an input with respect to the processor. The command
and data tokens to be written are sent on the MMCMD signal and the response and read data tokens
are received on the MMDAT signal.
Figure 15-4
shows a typical SPI mode timing diagram without
a data token.
Figure 15-5
and
Figure 15-6
show SPI mode read and write timing diagrams,
respectively.
Figure 15-2. MMC Mode Operation Without Data Token
Figure 15-3. MMC Mode Operation With Data Token
Command
MMCMD
MMDAT
Operation (No Response)
Operation (No Data)
Command
Response
from host to card(s)
from card to host
from host to card
Command
MMCMD
MMDAT
Data Transfer Operation
Data Stop Operation
Response
Data Stream
from
host to
from
stop command
stops data transfer
Command
Response
data to/from
Summary of Contents for PXA255
Page 1: ...Intel PXA255 Processor Developer s Manual January 2004 Order Number 278693 002 ...
Page 24: ...xxiv Intel PXA255 Processor Developer s Manual Contents ...
Page 30: ...1 6 Intel PXA255 Processor Developer s Manual Introduction ...
Page 310: ...7 46 Intel PXA255 Processor Developer s Manual LCD Controller ...
Page 330: ...8 20 Intel PXA255 Processor Developer s Manual Synchronous Serial Port Controller ...
Page 358: ...9 28 Intel PXA255 Processor Developer s Manual I2 C Bus Interface Unit ...
Page 488: ...13 36 Intel PXA255 Processor Developer s Manual AC 97 Controller Unit ...
Page 572: ...16 30 Intel PXA255 Processor Developer s Manual Network SSP Serial Port ...
Page 599: ...Intel PXA255 Processor Developer s Manual 17 27 Hardware UART ...
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