Atari 8-bit Virtual Disk Editor for the Macintosh.
Copyright 1995 Richard A. Carvel
Why have I written an Atari 8-bit virtual disk editor for the Macintosh? Although an emulator for the Mac hasn't been released yet to my knowledge, I DO have PCXFormer 2.5 and SoftPC Pro 3.1, so the program is useful for myself. (And, of course, it was fun to program a Mac project for the 8-bit!) At first, the program was for my own use, but I feel it has evolved to the point where others can use it too.
Anyone with a Macintosh and at least SoftPC Pro, or access to PC's, can use the program. I hope it will also be useful when a Macintosh emulator is released.
Now the minority of Atari 8-bit enthusiasts who use a Macintosh have something to play with! :)
AtariVD Editor can edit Atari 8-bit virtual disks in these file formats:
ATR: Nick Kennedy's SIO ATR file format with a 16 byte header.
XFD: No header. File contains only the disk sectors themselves.
ATD: AtariDisk format. Has a 16 byte Macintosh header.
AtariVD Editor is capable of reading, writing, and creating virtual disks in both Atari DOS 2.x and MyDOS 4.5 formats. In MyDOS format, you can create virtual disks from 720 to 65535 sectors of 128 or 256 bytes. Keep in mind that MyDOS assumes high capacity disks have 256 byte sectors, however.
Virtual Disk File Editor features
Atari 8-bit files on a virtual disk may be cut, copied, pasted, or erased using the standard edit menu commands. A file is extracted by selecting "Extract Atari File" or by double-clicking on the file. Import files into a virtual disk with the "Add File..." command.
A copy of an open virtual disk may be saved in a different file format using the available "Save as..." commands. The program will NOT replace an already open file.
The four buttons next to the file list are for working with MyDOS directories. "Main" returns to the top directory level, "Open" opens a selected directory, "Create" creates a new empty subdirectory in the current directory, and "Erase" deletes an empty subdirectory. Subdirectories may also be opened by double-clicking on them.
Sector Editor features
Each virtual disk window has a sector editor associated with it. Click the zoom box to enable or disable it. Bytes in a sector can be edited in either hexadecimal or ASCII form. Type <return> while the byte edit box is active or click the "Write Sector" button to save a change. The current sector is changed by typing a number from 1 to a disk's last sector in the sector edit box, then pressing <return>. The Tab key toggles between the sector# and byte editing boxes.
Entire sectors can also be copied and pasted to other open virtual disks using the "Copy Sector" and "Paste Sector" commands. *Note: modify sectors at your own risk.
"Find Byte" searches a sector for a byte match with an entered value. "Compare Sectors" looks for differences between the current sector in the active window and the last sector copied with the "Copy Sector" command, starting at a selected byte. If a mismatch is found, the copied sector's byte value appears in the edit box.
Limitations of this version:
1. You should write (and delete) MyDOS dos files only from the dos itself. AtariVD Editor will NOT make the MyDOS virtual disk bootable by writing the dos files.
2. The boot data in the first 3 sectors of a double density disk are written contiguously in the first 384 bytes after the header. I believe this is compatible with PCXFormer. However, this differs from the ATR format (according to the documentation I have) which stores the data in the first 128 bytes of each sector. My boot sector handling is still crude, so any help or info about MyDOS boot sectors is much appreciated.
System Requirements:
AtariVD Editor 1.1 should run on any Mac using System 7.0 or later.
Version History:
1.0 Initial version.
1.1 Minor bug fixes, sector editor added.
Planned future enhancements:
Refined MyDOS boot sector handling.
Disk Communicator 3.2 (.DCM) file extraction/encoding.
Please email any bug reports, helpful comments, etc., to:
