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AMSDOS Header

717 bytes added, 15:23, 21 April 2012
Created page with "In [[AMSDOS]] it is possible to store files in two ways: headerless and with a header. Headerless files are often files which were created with [[OPENOUT]] and ''SAVE"filename",a..."
In [[AMSDOS]] it is possible to store files in two ways: headerless and with a header. Headerless files are often files which were created with [[OPENOUT]] and ''SAVE"filename",a''. Programs normally have a file header, which is consists of 128 bytes and contains the following data:

<pre>
Byte 00: User number
Byte 01 to 08: filename
Byte 09 bis 11: Extension
Byte 18: type-byte
Byte 21 and 22: loading address
Byte 24 and 25: file length
Byte 26 and 27: execution address for machine code programs
Byte 64 and 65: checksum for byte 00 to byte 66
Byte 67 and 68: (file length)
</pre>

To calculate the checksum, just add byte 00 to byte 66 to each other.

[[Category:Programming]] [[Category:Disc Operating System]]
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