OOB中文解释【推荐详细去了解一下】
OOB： out of band，某些内存技术支持out-of-band数据——例如，NAND flash每512字节的块有
16个字节的extra data，用于纠错或元数据。
A NAND page consists of a number of data bytes (512 in the Neo1973 GTA01 case, 2048 in the GTA02 case) plus a number of out-of-band (OOB) bytes (GTA01: 16, GTA02: 64).
Only the data bytes are used for application data. The OOB bytes are used for
- Marking an erase block as bad (first or second page of erase block)
- Storing ECC (error correction codes)
- Storing filesystem specific information (JFFS2)
more info about OOB can refer here
Terminology术语
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Page – NAND addressable unit (normally 512b or 2Kbyte size) – can
be read, written, marked bad. Has associated OOB.
页-NAND地址单元(通常是512或者2K字节大小)-可以被读、写、标记为坏块。被联合OOB。
Block – Eraseable unit. 64 Pages. (128K on 2K NAND, 32K on 512b NAND)
块-可擦单元。64页。(128K在2K NAND,32K 在512B NAND)
OOB – ‘spare area’ of each page for ECC, bad block marked and YAFFS
tags. 16 bytes per 512b – 64 bytes for 2K page size.
OOB-每一个页上空余的区域,用于ECC。坏块被标记和YAFFS标签。每512B16字节-2K页大小有64字节。
Chunk – Basic YAFFS addressable unit. Same size as Page.
大块-基础YAFFS可设地址单元。同样的大小如同页一样。
Object – YAFFS Object: File, Directory, Link, Device etc.
对象-YAFFS对象文件，目录，链接，驱动等。