Applesauce
The Applesauce project was started in March 2017 by John K Morris of EvolutionInteractive.com. John is a well know programmer in his own right, however this is his most important contribution to the Apple II Community to date.
Background
In early 2017 John and Henry from ReActiveMicro were discussing project ideas mostly based around the Raspberry Pi. Henry sent John some hardware and after a few weeks of tinkering and discussing different projects John mentioned an idea he had involving floppy drives and backing up software. John knew Henry had worked on the EDD project and fixed several issue as a consultant for UltimateApple2 and they started to discuss how horrible and unreliable at best the EDD was in its attempt to capture the data which represents "the floppy". John started to talk about what if we attacked the problem of copying protected disks directly from the drive rather than trying to intercept the data stream from the drive under use like the EDD did. This was the start of what would become the Applesauce project.
John discovered it would not be possible to copy disks on-platform as the Apple II is too slow and too dependent on the Disk II Controller card. There would be no way to capture the timing data coming from the drive which occurs every 4 microseconds. In order to fully read a floppy disk as "raw data", also know as the flux patterns, he would need to take the drive off-platform and control it directly.
After some research about how the Apple II encodes floppy disks John found the only one to get things right is Jim Sather in his book Understanding the Apple II. All the other books and resources seem to have major flaws in their interpretation of how things work and plagiarized from one another. It is quite possible that John may be one of the few people besides Wozniak and Sather to actually understand how the whole floppy subsystems actually work.
By March 2017 John had started to look in to how to control the Disk II Drive and its power requirements. After some research he found the drive should be able to be controlled by a microcontroller. However most microcontrollers are not 5v tolerant and would need active and bidirectional level shifting. A proper speed microcontroller would also be needed in order to provide enough resolution to handle all the data being read from the floppy disk and allow enough time to control the drive.
A major issue would also be how to determine where the disk is in relation to the drive. This is called synchronization. IBM PC drives use a sensor to track synchronization which allows for less floppy controller processing requirements and simpler controller design to navigate tracks and sectors. The Disk II drive however does not track synchronization which some copy protections relied on and would make copying these protected disks impossible on-platform. In order to over come this issue John designed a sync sensor with the help from Henry and added it to the arbor of the Disk II drive.
The Disk II drive's power requirements also posed some issues as the power supply would need to support universal AC input to allow for international use, and also be tri-output in order to power the Disk II drive and its logic board.
There have been other similar projects such as Kryoflux and Catwheesel, however these projects have fallen short in several areas especially where Apple II is concerned.
What Is Applesauce?
Applesauce comprises two parts - hardware and software.
The hardware component of the project is a "Controller Interface" that allows an Apple II Floppy Drive to be connected via USB to a modern computer.
The software component runs on the modern computer and controls the Floppy Drive and captures a data stream from the inserted disk.
Once this data stream is captured, the Applesauce software can then process the data for saving as disk image files.
Because Applesauce captures the data on the disk at the flux level, it is able to capture Apple II copy-protection schemes "in place".
The resultant disk image could have its copy protection cracked, or it can be written back to a physical disk by the Applesauce software with protection in place, or (subject to emulation hardware or software support) it can be used with copy protection left in place in the disk image in Apple II emulators or solid state Apple II disk drive emulators.
For non-protected (or previously cracked disks), Applesauce is able to capture a .dsk disk image in approximately 11s.
Blah blah... crap.
Teensy
Info on exactly what is the Teensy and what it does.
Sync Sensor
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