! Description
|-
| 1 2| Sector Size and Flags?
|-
| 1 | Flags?|-| ?
| Compressed sector data
|}
9 means same byte for entire The Sector Size and Flags are stored as a word (LSB first), containing the stored data length (when not empty), compression flag, and deleted data address mark. The top 3 bits of the Size are flags, with the bottom 13 bits containing the size of the stored data (when not empty). A sector? 80 which does not have a deleted data address mark and contains only E5 bytes is considered empty. In this case, the byte? then there top 3 bits will be 100 and the size is no ignored. WinAPE stores this as #8009, but it could be any value from #0000 to #1FFF or #8000 to #9FFF. For all other sectors: {| border="1"|-! Bit! Description|-| 15| RLE compressed sector if set (see below)|-| 14| Sector has Deleted Data Address Mark (DDAM)|-| 13| Sector data is present (not empty)|}
== Compression scheme ==