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8k Speedlock

340 bytes added, 05:58, 13 February 2022
Fixed language, added supplemental information
Speedlock is a tape and disc copy protection solution.
'8K Speedlock ' refers to a specific version of the Speedlock where most of the data was stored on special specially formatted tracks. Each track was setup with [[µPD765]] sector size 6, which indicated a sector with 8,192 (&2000) bytes of data. However in reality, only 6,146 (&1800) bytes were useable. Recreating this format on the Amstrad was difficult because the µPD765 would try to write 8,192 bytes of data, and in doing so it would wrap around on itself and corrupt the sector data header thereby making it impossible to read.
Each track Internally the format was setup with [[NEC765]] sector size 6known as "Indy", which indicated a sector with 8192 (&2000) bytes of data. However in reality, only 6146 (&1800) bytes were useable.Recreating this format on reference to the Amstrad fact that it was difficult because the NEC765 would really try necessary to write 8192 bytes of synchronize data, writing with the index hole and in doing so it would corrupt use special hardware to avoid the MFM wrap around. This synchronization was deliberately not maintained during duplication, thereby enabling data structure used to layout the sectors on the trackload more quickly.
[[Category:Copy Protection]]
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