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ZX Interface 1: Difference between revisions
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→Microdrive Data Storage Format
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Each sector consists of two files, each similar. There is the Sector Header, which is a 15 byte file record, or the data record recorded after the sector header, which is 528 bytes, including one "sacrificial byte" on the D1 data line, which does not contribute to the data stored, though could be modified into a high-order byte checksum in the future to improve data integrity on older cartridges. | Each sector consists of two files, each similar. There is the Sector Header, which is a 15 byte file record, or the data record recorded after the sector header, which is 528 bytes, including one "sacrificial byte" on the D1 data line, which does not contribute to the data stored, though could be modified into a high-order byte checksum in the future to improve data integrity on older cartridges. | ||
[[File:Logic_Analysis_of_sector_Header_and_Data_sections_with_gaps.png]] | |||
[[File: | |||
Each of these structures is similar, apart from length, and can be examined independently. | Each of these structures is similar, apart from length, and can be examined independently. From this image, it can be seen that the ERASE line turns on just before the R/W line begins writing the sector. In this case, the Sector Header has been read, and it has been determined previously when the sector map was constructed that this sector can be written to. The ERASE is activated, and then the R/W is activated (active low ) just prior to writing data. | ||
== External links == | == External links == | ||