Sandisk SDDK-07 User Manual

© 2003 SanDisk Corporation 

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10/2003 

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At any given operational state, the maximum buffer required is 1K, except during the 
download or playback states. These two depends on the host system 

This layer encapsulates the SD Security, and SD Secure Files System. Using the API, SD-Audio layer can access 
this layer, and all the complexity of MKB process, AKE process, Bus Encryption/Decryption, and Audio Content 
Encryption/Decryption is hidden from the application layer. 

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AKE process is handled in this layer 

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Bus Encryption/Decryption is performed immediately after each AKE process 
successfully finished 

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MKB process is handled in this layer, its been invoked during the SD-Audio initialization 

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To support the download operations, generating title key method implemented in this 
layer 

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Title Key encryption/decryption 

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Audio content encryption/decryption 

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Secure file manipulation such as (open, read, delete, write, etc.) handled in this layer 

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Required buffer in this layer is 1.5 Kbytes for internal use, this is need for the MKB 
process after the MKB process is complete this layer only require 512 bytes for other 
operations 

This layer provides full FAT file system interface to SD card user area with API functions such as create, delete, 
insert, merge files, sub-directories, file date/time, file attributes and volume labels. 

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Support for FAT12, FAT16 and FAT32 

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Support for short and long file names 

This layer handles all low-level I/O access to MMC card and SD card. It provides eight functions. They are: 
xxx_init, xxx_drive_open, xxx_drive_close, xxx_read, xxx_write, xxx_erase, xxx_read_serial, where xxx is the 
peripheral bus name, such as MMC or SPI. 

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Hardware access to memory card is through SanDisk verilog host controller. 

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SD protocol, MMC protocol are implemented and tested on the top of the verilog host 
controller. 

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SPI protocol is implemented but not tested on the top of the verilog host controller, due 
to the limitation of the host controller in SPI mode.

There are four directories under the SD_SDK directory.