JFFS2 Out of Band usage
JFFS2 uses the default autoplacement scheme. The only JFFS2 specific usage of the oob area is the storage of the cleanmarker
Nand chips with 256 byte pagesize and 8 byte OOB size
| Offset | Content | Comment |
| 0x06 | Clean marker byte 0 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x85. In the remaining pages this byte is reserved |
| 0x07 | Clean marker byte 1 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x19. In the remaining pages this byte is reserved |
Nand chips with 512 byte pagesize and 16 byte OOB size
| Offset | Content | Comment |
| 0x08 | Clean marker byte 0 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x85. In the remaining pages this byte is reserved |
| 0x09 | Clean marker byte 1 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x19. In the remaining pages this byte is reserved |
| 0x0a | Clean marker byte 2 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x03. In the remaining pages this byte is reserved |
| 0x0b | Clean marker byte 3 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x20. In the remaining pages this byte is reserved |
| 0x0c | Clean marker byte 4 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x08. In the remaining pages this byte is reserved |
| 0x0d | Clean marker byte 5 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
| 0x0e | Clean marker byte 6 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
| 0x0f | Clean marker byte 7 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
Nand chips with 2048 byte pagesize and 64 byte OOB size
| Offset | Content | Comment |
| 0x10 | Clean marker byte 0 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x85. In the remaining pages this byte is reserved |
| 0x11 | Clean marker byte 1 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x19. In the remaining pages this byte is reserved |
| 0x12 | Clean marker byte 2 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x03. In the remaining pages this byte is reserved |
| 0x13 | Clean marker byte 3 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x20. In the remaining pages this byte is reserved |
| 0x14 | Clean marker byte 4 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x08. In the remaining pages this byte is reserved |
| 0x15 | Clean marker byte 5 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
| 0x16 | Clean marker byte 6 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
| 0x17 | Clean marker byte 7 | This byte indicates that a block was erased under JFFS2 control. If the page was succesfully erased this byte in the first page of a block is programmed to 0x00. In the remaining pages this byte is reserved |
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