Instead, Apple supplied on the System Master disk a conversion program called “MUFFIN” to allow files to be moved from 13 sector to 16 sector disks.Įnterprising hackers in the Apple II world made modifications to MUFFIN and created DE-MUFFIN, a DOS 3.2 utility to convert the files back to the 13 sector format. It could have been incorporated into DOS 3.3, but would have called for a major effort in rewriting the track and sector access routines, as well as making DOS larger than the earlier versions. īecause of the changes in the ROM controller, it was not easy to read disks formatted under DOS 3.2 directly from DOS 3.3. (Also, a separate disk called “BASICS” was included that could be used in the same way as a pre-boot for 13 sector disks). To allow users to startup their older 13 sector DOS 3.2 disks, a binary program called “BOOT13” was included. The newer COPY programs also worked properly on single drive systems (previously, you had to have two disk drives in order to use this program to copy a disk). The “COPY” program (used to copy entire disks) was translated to Applesoft as “COPYA” for those II Plus users who didn’t have access to Integer BASIC. The DOS 3.3 System Master disk included many programs that had previously been present on the DOS 3.2 Master, plus a few others.
Apple disk map manual#
An updated and greatly expanded version of the DOS manual was also included in the DOS 3.3 upgrade.
Apple disk map upgrade#
Those users who bought this upgrade to DOS 3.3 had to change the ROM chip on the disk controller (or have their dealer do it for them). Only the ROM program on the Disk II controller card needed to be changed to make the move to DOS 3.3. The remarkable thing about this upgrade was that the disk drives themselves did not need to be changed to make this possible. This resulted in a disk that could now hold a maximum of 140K of data (124K excluding DOS and the catalog track), a 23 percent increase over the 13 sector disks. Changing slightly the method used for encoding data on the disk made it possible to have 16 sectors per track, instead of the original 13 sectors per track in DOS 3.1 and 3.2.
Apple disk map driver#
Steve Wozniak, the author of the original DOS disk driver ( RWTS), had found a way to increase the storage capacity of Apple floppy disks. Since it was designed to have DOS present on each disk in the first three tracks, and the catalog took up another entire track, there was actually only 100.75K available for data storage. At 256 bytes possible per sector, this made the disk capable of holding 113.75K of information. The original disk drive had been designed with the ability to read and write 35 tracks of 13 sectors each on a 5.25 inch disk. It consisted of not only a new System Master disk, but a hardware upgrade chip as well. In August of 1980, Apple released an upgrade for DOS, to version 3.3.
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