111 lines
2.1 KiB
INI
111 lines
2.1 KiB
INI
Macintosh 7 & 8 bit File Transfer Format - Protocol Independent
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Here is a description of the Hqx7 (7 bit format as implemented in BinHex
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4.0) and Hqx8 (8 bit format) formats for Macintosh Application and File
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transfers. The main features of the formats are:
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1) Error checking even using ASCII download (Hqx7 & Hqx8)
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2) Compression of repetitive characters (Hqx7 & Hqx8)
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3) 7 bit encoding for ASCII download (Hqx7)
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HQX Format Description (This is not intended to be a programmer's reference).
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The format is processed at three different levels:
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1) 8 bit encoding of the file:
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Byte: Length of FileName (1->63)
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Bytes: FileName ("Length" bytes)
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Byte: Version
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Long: Type
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Long: Creator
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Word: Flags (And $F800)
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Long: Length of Data Fork
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Long: Length of Resource Fork
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Word: CRC
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Bytes: Data Fork ("Data Length" bytes)
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Word: CRC
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Bytes: Resource Fork ("Rsrc Length" bytes)
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Word: CRC
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2) Compression of repetitive characters.
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($90 is the marker, encoding is made for 3->255 characters)
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00 11 22 33 44 55 66 77 -> 00 11 22 33 44 55 66 77
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11 22 22 22 22 22 22 33 -> 11 22 90 06 33
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11 22 90 33 44 -> 11 22 90 00 33 44
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3) 7 bit encoding (Hqx7 only).
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The whole file is considered as a stream of bits. This stream will
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be divided in blocks of 6 bits and then converted to one of 64
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characters contained in a table. The characters in this table have
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been chosen for maximum noise protection.
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The format will start with a ":" (first character on a line) and
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end with a ":". There will be a maximum of 64 characters on a line.
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It can be preceeded by comments for novice users.
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Table:
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!"#$%&'()*+,-012345689@ABCDEFGHIJKLMNPQRSTUVXYZ[`abcdefhijklmpqr
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Comment:
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(This file must be converted with BinHex 4.0)
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Yves Lempereur [YVES]
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