CP2 - Revision history

John e: /* File structure */

2025-07-04T21:20:29Z

‎File structure

John e: /* File structure */

2025-07-04T16:42:30Z

‎File structure

John e: Created page with "{{FormatInfo |formattype=electronic |subcat=Disk Image Formats |extensions={{ext|cp2}} }} '''CP2''' is a disk image format created by the commercial disk copier Copy-II-PC in ..."

2025-07-04T16:38:56Z

Created page with "{{FormatInfo |formattype=electronic |subcat=Disk Image Formats |extensions={{ext|cp2}} }} '''CP2''' is a disk image format created by the commercial disk copier Copy-II-PC in ..."

New page

{{FormatInfo
|formattype=electronic
|subcat=Disk Image Formats
|extensions={{ext|cp2}}
}}
'''CP2''' is a disk image format created by the commercial disk copier Copy-II-PC in conjunction with a separate program, Snatch-It.

== Identification ==
The first 24 bytes of the file are ASCII 'SOFTWARE PIRATESRelease '.

== File structure ==
Files begin with a 30-byte header:
<pre>
+0x00 DB 'SOFTWARE Pirates'
+0x10 DB 'Release '
+0x18 DB release (printable ASCII)
+0x1C DB '$'
+0x1D DB volume number (ASCII, starting with '0')
</pre>
Following the header will be one or more segments, each 64k or less in size. A segment is formed:
<pre>
+0x00 DW segment header length, little-endian word.
+0x02 DB cylinder
+0x03 DB head
+0x04 DB sector
+0x05 Sector headers, 384 bytes per track.
DW length of sector data
DB sector data
</pre>
The length

A sector header is 16 bytes:
<pre>
+0x00 DB read result
+0x01 DB 8272 status register 0
+0x02 DB 8272 status register 1
+0x03 DB 8272 status register 2
+0x04 DB Sector ID: cylinder
+0x05 DB Sector ID: head
+0x06 DB Sector ID: sector
+0x07 DB Sector ID: size (0 for 128 bytes, 1 for 256 bytes, 2 for 512 bytes etc.)
+0x08 DW Offset to sector data from start of sector data area + 0x16AD
</pre>
To find the actual offset of a sector in the file, take its offset value in the header, subtract 0x16AD, and add the segment header length +

== Software ==
* [h ttps://github.com/retrohun/pce/blob/master/src/drivers/psi/psi-img-cp2.c PCE] contains some code to parse .CP2 disk images.

== Sample files ==
* ht tps://discmaster.textfiles.com/browse/29984/wbiz0000-0009/wbiz0008.tar/wbiz0008

@@ Line 12: / Line 12: @@
 Files begin with a 30-byte header:
 <pre>
-+0x00  DB  'SOFTWARE Pirates'
++0x00  DB  'SOFTWARE PIRATES'
 +0x10  DB  'Release '
 +0x18  DB  release (printable ASCII)

@@ Line 28: / Line 28: @@
         DB  sector data
 </pre>
-The length
+To find the sector data length and sector data, take the offset in the file of the segment header and add the segment header length + 2. This address may overlap with the end of the last sector header.
-−
 A sector header is 16 bytes:
@@ Line 43: / Line 42: @@
 +0x08  DW  Offset to sector data from start of sector data area + 0x16AD
 </pre>
-To find the actual offset of a sector in the file, take its offset value in the header, subtract 0x16AD, and add the segment header length +
+To find the actual offset of a sector in the file, take its offset value in the header, subtract 0x16AD, and add the offset to the address of the sector data as determined from the segment header.
-−
 == Software ==