 |
|||||||||||||||||||||
|
|||||||||||||||||||||
| April 5th, 2007 ___________________________________________ mDOC devices by Dean Ramsier of the Windows CE 6 Team Greetings Sandisk has a family of DiskOnChip products (from recently acquired M-Systems) that are often used in Windows Embedded CE devices. These mDOC devices contain NAND flash as well as proprietary logic that presents a cpu friendly interface. NAND flash is typically less expensive and higher performance than NOR based flash, but requires a much more complex software implementation to handle error detection and correction. The combination of this proprietary on chip logic and software from Sandisk provides a complete storage solution based on the lower cost NAND flash. The latest H3 generation of devices pushes more of the software down into firmware on the mDOC itself, making future upgrades easier on the system developer. The mDOC devices are easily used as storage solutions in embedded devices. However they also provide a boot capability using a small amount of linear access memory inside the mDOC. This allows BSQUARE that do not have the ability to boot from raw NAND flash to still use a single chip NAND based solution. This type of implementation is also supported by libraries provided by Sandisk, but is considerably more complex to integrate than a storage only solution. The mDOC devices can be divided up into multiple partitions with different characteristics, with partitions dedicated to boot code, OS code, parameter storage areas, as well as file system partitions. BSQUARE has implemented a number of mDOC based designs and has integrated support for this technology in our SchemaBSP product. Designs using the SchemaBSP code base can immediately benefit from our experience using these parts, and take advantage of a number of mDOC related bootloader features. These include the ability to boot from the latest generation mDOC devices on a number of different BSQUARE, dynamically create OS and bootloader partitions, easily update the bootloader and OS partitions etc. OEMs considering booting from Sandisk mDOC devices should consider contacting BSQUARE to see how we may be able to speed up the development cycle. . . . . . . . . . . . . . . . . . . . . . . .
|
|||||||||||||||||||||
