RT809H Lost My Nand firmware

noori1

dear nasir what is the price of RT809H in Pakistan? i also want to buy it but after reading your problem i am afraid . so guide me do i bought it or not?

noori1

Http://www.ifix.net.cn/thread-59982-1-1.html
i AM sending you Link.
The After translating chines in English in Google trancelater It may Changes  some sentence Sequences so  Read Properly.
03,314,402,101

admin

首先，请搞清楚NAND和EMMC的差异，EMMC芯片内置控制器，管理坏块和对外的通讯，对于编程器来说，读写EMMC不需要考虑坏块问题，复制起来非常简单，成功率很高；但是对于NAND来说，编程器完整复制NAND，是很难做到的100%好用的，如果你不信，可以购买更贵的编程器，读取母片再写入多个新的芯片，看看是不是全部能用。
复制NAND有一个重要的原则：母片只能读取不要写入！
请准备多个相同型号的NAND芯片，分别写入测试，有个别字节校验不一致，并不影响使用。焊接NAND后一定要清洗烘干，很多问题是焊接、清洗造成的。
如果你不相信，提供SONY此款机型的板号和图片，我们会购买一片板子，然后拍视频教程给你看。


First of all, please understand EMMC and  NAND, EMMC chip built-in controller, bad block management and external communication, for programmer, reading and writing EMMC don't need to consider the bad block, clone is very simple, the success rate is very high; But for NAND clone, 100% is hard to do good, if you don't believe, you can buy more expensive programmer, read the mother again in multiple new chip, and see if it is all can use.

Copy the NAND has an important principle: the mother can only read ,do not write!

Please prepare more than the same type of NAND chips, written test respectively, have individual bytes check, does not affect the use. Must be clean after welding NAND drying, a lot of problems is caused by welding, cleaning.

If you don't believe, provide SONY this type of board number and take a photo, we will buy a piece of the board, and then shoot video tutorials to show you.

螺丝刀

admin 发表于 2017-2-15 21:55
首先，请搞清楚NAND和EMMC的差异，EMMC芯片内置控制器，管理坏块和对外的通讯，对于编程器来说，读写EMMC不 ...

NAND FLASH 闪存生产厂家三星在其产品DATASHEET里是这样描述坏块问题的：3.1 Initial Invalid Block(s)
Initial invalid blocks are defined as blocks that contain one or more initial invalid bits whose reliability is not guaranteed by Samsung. The information regarding the initial invalid block(s) is called the initial invalid block information. Devices with initial invalid block(s) have the same quality level as devices with all valid blocks and have the same AC and DC characteristics. An initial invalid block(s) does not affect the performance of valid block(s) because it is isolated from the bit line and the common source line by a select transistor. The system design must be able to mask out the initial invalid block(s) via address mapping. The 1st block, which is placed on 00h block address, is guaranteed to be a valid block at the time of shipment.
这让我们想到相似的硬盘坏道问题，坏道和闪存坏块一样不可绝对避免，因此有了相应的补救方法：把坏道mark下来让使用程序跳过坏道，上文中一句话“The system design must be able to mask out the initial invalid block(s) via address mapping.”提到的即是应用方应该将测出的坏块mark掉的方法来解决坏块不可避免的问题。所以希望809H厂家能增加对NAND FLASH闪存的记录屏蔽坏块的功能，应该说它是闪存写入功能的一部分。否则买一堆闪存闭眼写入，然后再一个个焊到板上试出好坏，这种盲目做法还真让人怀疑科学二字。非常抱歉给老大添麻烦了，言语若有不敬请多包涵。