Apple-2-Tools/AppleWin
1
0
Fork 0
mirror of https://github.com/AppleWin/AppleWin.git synced 2026-04-20 00:17:16 +00:00
Code Issues Projects Releases Wiki Activity

Document the disk image size magic numbers. (PR #1375)

Browse Source 
* Document the disk image size magic numbers (in source & help doc).
* Mention 40+ tracks after oddball disk sizes.
* Debugger 2.9.2.2: Fixed: DB HGR = 2000:3FFF was displaying help instead of being parsed.
* Debugger 2.9.2.3: Fixed: DB HGR = 2000:3FFF and DB FOO = 300 wasn't parsing correctly from 2.9.1.3. Fix for commit 48e0fe3a.
* Debugger: 2.9.2.4 Fixed: DA RESET = 3F2 was displaying help instead of being parsed.
* Debugger: 2.9.2.5 Added: Symbol table for DOS 3.3 using file A2_DOS33.SYM2
* Debugger: 2.9.2.6 Added: QoL: Turning a symbol table on/off now shows the current status.
This commit is contained in:
Michael "Code Poet" Pohoreski
2025-02-08 08:11:08 -08:00
committed by GitHub
parent bd87cae92c
commit 67896db65e
2 changed files with 45 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files
help/ddi-formats.html
+10 -2
View File
@@ -27,16 +27,24 @@ sectors. If you run a DOS program on the Apple which reads in
sectors one by one and then transfers them over a serial line to
the PC, you will get a DOS order disk image. </p>
<p>Apple floppy disks contained 35 tracks with
<p>Apple floppy disks (normally) contain 35 tracks with
16 sectors per track, for a total of 560 sectors. Each of these
sectors contained 256 bytes of information, for a total of
143,360 bytes per disk. Therefore, DOS order disk images are
always at least 143,360 bytes long. Sometimes on the Internet you
will see a disk image that is 143,488 or 143,616 bytes long; this
will see a disk image that is not 143,360 bytes long; this
is probably a DOS order image with extra header information
before or after the image. In most cases, AppleWin can
automatically detect this and handle it. </p>
<p>Due to some games being incorrectly converted to a disk image AppleWin also accepts disk images of sizes:
<ul>
<li>143,403 bytes (<i>Castle Wolfenstein</i>)</li>
<li>143,488 bytes (<i>Rescue Raiders</i>)</li>
</ul>
<p>Some disk drives were able to handle 40+ tracks. AppleWin accept disk images up to 40 tracks -- 163,840 bytes -- as long as the disk image is a multiple of 4,096 bytes / track.</p>
<p style="font-weight: bold;">ProDOS Order
Images: </p>
source/DiskImageHelper.cpp
+35 -4
View File
@@ -601,10 +601,41 @@ bool CImageBase::IsValidImageSize(const uint32_t uImageSize)
}
else
{
// TODO: Applewin.chm mentions images of size 143,616 bytes ("Disk Image Formats")
bValidSize = ( ((uImageSize >= 143105) && (uImageSize <= 143364)) ||
(uImageSize == 143403) ||
(uImageSize == 143488) );
// AppleWin.chm (Disks and Disk Images > Disk Image Formats) used to mention disk images of sizes 143,488 and 143,616 bytes
// "Sometimes on the Internet you will see a disk image that is 143,488 or 143,616 bytes long;"
// ... but doesn't mention where these magic numbers come from.
// Also, AppleWin doesn't even check for the 143,616 size!
//
// Mame in mame/src/lib/formats/ap2_dsk.cpp checks for sizes ...
// 143403,
// 143363,
// 143358, and
// 143195
// ... but also doesn't list references/sources/examples.
//
// Searching the Internet for these disk sizes we find them in a mame commit from 2019!
// https://github.com/mamedev/mame/commit/b380514764cf857469bae61c11143a19f79a74c5
// They are in the old file hash/apple2.xml. It has been renamed/moved to apple2_flop_misc.xml
// https://github.com/mamedev/mame/blob/master/hash/apple2_flop_misc.xml
//
// | Size | # | Disk Image Name |
// |-------:|--:|:---------------------------------------------------------------------------------------|
// | 143105 | ? | ??? Smallest Valid Size ??? |
// | 143195 | 1 | bard's tale iii - the thief of fate, the (1988)(interplay)(disk 3 of 4)(dungeon 1).dsk |
// | 143358 | 1 | bard's tale iii - the thief of fate, the (1988)(interplay)(disk 1 of 4).dsk |
// | 143358 | 2 | bard's tale iii - the thief of fate, the (1988)(interplay)(disk 2 of 4)(character).dsk |
// | 143358 | 3 | bard's tale iii - the thief of fate, the (1988)(interplay)(disk 3 of 4)(dungeon 2).dsk |
// | 143363 | 1 | bandits (1982)(sirius software)[o].dsk |
// | 143363 | 2 | berzap (1984)(infinity limited)[cr krackle - magic merlin][o].dsk |
// | 143363 | 3 | f15_strike_eagle.dsk |
// | 143364 | ? | ??? Largest Valid Size ?????? |
// | 143403 | 1 | castle wolfenstein (1981)(muse).do |
// | 143488 | 1 | rescue_raiders.dsk |
//
// NOTE: Update help/ddi-formats.html if the following disk sizes change.
bValidSize = ( ((uImageSize >= 143105) && (uImageSize <= 143364))
|| (uImageSize == 143403) // 43 byte header (Pre or Post?) + 35 Tracks * 16 Sectors/Track * 256 Bytes/Sector
|| (uImageSize == 143488) ); // 128 byte header (Pre or Post?) + 35 Tracks * 16 Sectors/Track * 256 Bytes/Sector
}
if (bValidSize)