EDD Plus Card
|EDD Plus Card|
|Type||Drive Controller/Copy Card|
|Compatibility||II, II+, IIe, IIGS|
The EDD Plus Card was sold with some versions of the EDD (Essential Data Duplicator) 4 Plus bitcopy program. It is an auxiliary disk drive controller designed by Charles Rosenberg that goes between the Apple II floppy disk controller and floppy disk drive that intercepts the raw data stream from the drive and passes it to the EDD 4 Plus program. The card was placed in an unused slot, usually slot 5, and the floppy drive cable is plugged into it. A second cable connects the EDD Plus Card to the normal Apple floppy disk controller in slot 6.
Essential Disk Duplicator
Essential Disk Duplicator 4 Plus is a bit copy program that can utilize the EDD Plus Card to make copies of disks that other software-only bit copiers may have trouble copying. Version 4.4 and earlier do not run properly on a IIGS, but can be patched to do so using Brian A. Troha's single byte patch that was published in issue #61 of Computist magazine.
In addition to backing up disks, EDD 4 Plus includes several utilities to examine and analyze disks, display disk drive speed, certify disks, etc.
EDD 4 Source Code
Although the EDD 4 software disk was heavily copy protected, the publisher offered registered owners the opportunity to purchase a 6502 Assembly Language Source Code Listing of the EDD 4 program to see the "insides" of the program for educational purposes. This source code listing is of the EDD version 4.2 disks recorded on April 23, 1986 and is for the BIG MAC assembler. The file also contains a section on "Plus Card Technical Information and Software Interfacing".
Bob Brown's Homebrew EDD Plus Card
Bob Brown reverse-engineered an EDD Plus card and drew up this schematic. He then built a homebrewed card to verify his schematic, and ended up making some improvements to the original design.
UltimateApple2 EDD+ Data Duplication Card
In 2008 UltimateApple2 released their version of the EDD Plus card, called the EDD+ Data Duplication Card. It was a clone of the original card with LEDs added to indicate read and write status. The UltimateApple2 store is currently "on hiatus" and it is unknown when it will reopen.
I'm fEDD up
In October of 2012 Antoine Vignau and Olivier Zardini, founders of Brutal Deluxe Software, released a new program called "I'm fEDD up" that can take advantage of the EDD Plus card to archive and preserve 5.25" Apple II disks. The software uses the EDD Plus or compatible card (including the UltimateApple2 version) to capture the raw data from the disk at the bit level, before any processing.
EDD 4 Plus Software v4.9 - This version of the Essential Data Duplicator software requires the EDD Plus Card to be installed and will run on a IIGS, as well as earlier Apple IIs. This is a Shrinkit disk archive (.sdk) of a bootable 5.25" DOS 3.3 diskette.
EDD 4 Plus Software v4.2 - This version of the Essential Data Duplicator 4 Plus program can be used without the EDD Plus card, but will use it if it is available. It will not run on a IIGS unless a one-byte patch is applied. This is a Shrinkit disk archive (.sdk) of a bootable 5.25" DOS 3.3 diskette.
This Softkey for EDD 4 by Brian A. Troha that leads you step-by-step through a boot trace of the disk appeared in issue #49 of Computist magazine.