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Line 45:
Line 45: − The 2 bytes that follow the blockmap are the CRC16 (with starting value 0xFFFF (like modbus)) of the first 8 bytes and the blockmap. Line 67:
Line 66: − With magic being a constant 0x080d6ce0.+ − The checksums in the blockmap/journal entries work as follows:+ − + − +
→Wear leveling
blockmap后2字节为最开始的8个字节，以及blockmap的CRC16校验码（开始值为0xFFFF（像modbus））。
blockmap后2字节为最开始的8个字节，以及blockmap的CRC16校验码（开始值为0xFFFF（像modbus））。
然后是journal。其结构如下:
然后是journal。其结构如下:
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magic 是一个固定值 0x080d6ce0.
blockmap/journal入口的验校和是这样工作的:
* each byte is the checksum of an encrypted 0x200 bytes large block
* 每个 byte 是一个 0x200 大小加密的块的验校和
* to calculate the checksum, a CRC16 of the block (with starting value 0xFFFF) is calculated, and the two bytes of the CRC16 are XORed together to produce the 8bit checksum
* 计算一个块的CRC16 (从 0xFFFF 开始) ,两个byte的CRC16一起进行异或运算，以产生 8bit 校验和
=== Partitions ===
=== Partitions ===