Re: Convert AppleWriter 1.0 binary files to text files

[Andy McFadden <fadden@fadden.com>]

Peter Ibbotson <spambox@ibbotson.demon.co.uk> wrote:
>> Reading on the web, AppleWriter 1.x stored the files at binary files,
> which
>> is accurate with what I have (AppleWriter 2.0 started storing files as
> text
>> files). Fortunately, one of the disks has AppleWriter 1.0 on it, and I'm
>> able to run the program and read the files.

> IIRC the text format just has the high bit set, it certainly wasn't anything
> special. I remember using it as the editor for an assembler I wrote for DOS
> 3.3. Best bet is to try some simple bitmasks.

Almost.  It looks like capital letters show up in the control character
range, and lower-case letters show up as upper-case ASCII with their high
bits set.  Space is 0xe0 instead of 0xa0.  For example, the CiderPress
hex dump shows:

00000000: 83 09 ce d4 d2 cf c4 d5 c3 d4 c9 cf ce fa e0 e0  ..NTRODUCTIONz``
00000010: 0f c6 e0 c1 cc cc e0 d4 c8 c5 e0 d4 c5 c3 c8 ce  .F`ALL`THE`TECHN
00000020: cf cc cf c7 c9 c3 c1 cc e0 c4 c5 d6 c9 c3 c5 d3  OLOGICAL`DEVICES
00000030: e0 c9 ce d4 d2 cf c4 d5 c3 c5 c4 e0 c9 ce e0 d4  `INTRODUCED`IN`T
00000040: c8 c5 e0 cc c1 d3 d4 e0 c3 c5 ce d4 d5 d2 d9 ec  HE`LAST`CENTURYl

This doesn't trigger the automatic high-ASCII detector because there's
low-ASCII stuff at the start of every sentence... looks like binary.  If
we assume that what is shown above is what was stored directly into screen
memory, then it makes sense: lower-case letters as normal upper-case
text, and upper-case letters as inverse upper-case text.

It appears to use high-ASCII control chars in a few places, e.g. 0x03
at the start above and 0x8d for hard returns.  There are also some
occurrences of high-ASCII lower case letters that appear to be used for
formatting commands.

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