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Siemens AG Semiconductors
Version 5.2
Confidential
20/10/1998
20
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The adapter is divided into two major parts:
The controller: macro unit, stack management and power management
The datapath: Adapter interface, read cache, write buffer, CRC unit and MultiMediaCard bus
interface
The width of the data path is a byte; the units which are handling data work on bytes or blocks of
bytes, too. Blocks are multiples of bytes. So the smallest unit of a control unit or data access is a
byte.
The architecture of the following MultiMediaCard adapter subunits will be described here:
MultiMediaCard bus interface: the MultiMediaCard bus master and interface.
Adapter interface: the interface to an application adapter or microprocessor.
Stack management:this unit stands for card stack management functions and information.
Data buffer:
to support a continuous data transfer with minimal access latency and a fast
burst write.
CRC unit:
generates and checks CRC bits for every command/response and data
block.
Power management: this unit will generate sequences like power up/down, reset and program-
ming voltage.
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MultiMediaCard adapter
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