The Development Of Experiments Platform For Nand Flash

Due to the high speed,small size,lage storage capacity,strong anti-vibrationperformance characteristics,NAND Flash has been a wide range of use.However,due to the bad blocks and not continuously addressing shortcomings,existing diskmanagement approach is no longer suitable for NAND Flash Memory,the scientistsare actively seeking ways to solve the problems. There is no unified algorithmverification platform; it is urging to design a universal verification platform tointuitive evaluation of NAND Flash management algorithm. Based on thoroughanalysis of the operating characteristics of NAND Flash and NAND Flashmanagement algorithm research direction, we have developed a hardware-softwareco-design experiments platform for NAND flash based on Xilinx all programmableZynq-7000Soc.In the aspect of hardware, we have adopts a newly all programmable Soc Zynqproduce by Xilinx company as main control chip. We use the Zynq embedded PL(Programmable Logic) to achieve a NAND Flash controller, data transmissioncontrol module, the introduction of data errors module and bad block managementmodule.Among them, the NAND Flash controller adopts double ping-pong cache toenhance the data writing speed, data transmission control module adopted the AXIGP interface to realize the control by PS(Processing Syatem) on the one hand, onthe other hand, AXI DMA was realized using the HP AXI interface in order toachieve high speed data transmission between PS and PL. Data error introducedmodule through the AXI GP interface to get the wrong position given by PS, andcan realize the dislocation in NAND Flash page programming. Bad blockmanagement module in addition to the normal read, write, and erase the failure ofthe bad block markers and mapping, also uses Xilinx HLS tool implements theBCH error correction algorithm to find bad block of data error and marked withheavy mapping.In PS, we have transplanted real-time operating system FreeRTOS formanagement application. Used the Zynq embedded USB controller implements theUSB mass storage class to introduce a variety of file system algorithm. Throughtransplantation LwIP TCP/IP protocol stack to achieve the gigabit Ethernettransmission, complete the uploading necessary data which is useful to analysis the algorithm performance analysis in time. Finally, this paper use PS realized classicpage mapping algorithm, FAST FTL algorithm as other FTL algorithm referencedatum and running environment of advanced algorithms such as data compression,and aiming at the shortcomings of the existing commercial software, design thesupplement test software to evaluate the performance of the NAND Flashmanagement algorithm with the common indictors.The test result shows that the verification platform can validate NAND Flashmanagement algorithm and gives intuitive evaluation results.