Research And Design Of ROM Writer Software Based On NAND Flash Management Architecture For Embedded Devices

As the developing of the iOS and Android user operation system in embedded mobilephone industry, new smart phone becomes more and more popular, getting more marketshare which was occupied by feature phone. With the evolution of the product form, somenew demands are required in the production line process accordingly.For the consideration of various factors such as the form of products, demand, andfunction, NAND Flash is widely used as power-down storage devices of mobile phone inthe mobile phone industry. NAND Flash, due to the special nature of the process, must beoperated and maintained by special algorithm or management software, and the quality ofthe algorithm or management software will greatly affect the performance and efficiencyof the equipment. XSR Flash memory management architecture, which is widely used asNAND Flash management software in the current mobile phone industry, is widely used inhigh-end flagship smart phone of major brands and low-end feature phone of medium andsmall brands, and its stability, performance and efficiency have been mass-productiontested.In the era of feature phone, due to the small software program size and the shortdownload time, there is no need to use the ROM Writer download method which is faster and more efficient in the production line process.Even if some projects used ROM Writerdownload, they were rarely based on the XSR flash management architecture. With thegrowing size of the smart phone software, and download time of the software gettinglonger and longer, the previous production line process gradually doesn’t apply to therequirements for the development of the industry. On the other hand, ROM Writer becomesmore and more necessary to enhance the efficiency and cut the cost of the production lineobviously on the very large volume products. And ROM Writer for NAND Flash devicesshould be designed based on the flash management software that used by mobile phone,which is different from the traditional direct writing. The design of the ROM Writer basedon the XSR architecture, which is widely used in the flash management software in themobile phone industry, is urgently needed. Although the ROM Writer technique is alreadya mature market technology, ROM technology based on XSR Flash managementarchitecture, which adds new requirements in ROM Writer to improve the management ofNAND storage optimization, is a new demand in the current smart phone market.This paper analyses the XSR flash management architecture deeply, design andimprove the ROM Writer software based on the XSR architecture. The ROM Writerprocess mainly realizes the generation of XSR Reservoir area for management, andconstructs the remapping table used to replace the bad blocks of NAND device, andextends calculating3bytes ECC check code per512bytes to better match the sector size ofNAND Flash basic unit according to the current algorithm of calculating3bytes ECCcheck code per256bytes for1bit error detection and correction. Ultimately, based on therealization and optimization of the ROM Writer design for the XSR management structure,it would effectively enhance the efficiency of the production line, reduce the costs, andachieve the expected results.