CompuServe Messages

AMAX

    19-Mar-90 22:40:31
Sb: #94423-AMAX
Fm: Ed Bercovitz 76314,3340
To: Mike Schiller 76416,3065
Mike, The problem of disk interchangeability between the Mac and the Amiga is due to (as Betty has explained) the fact that the Mac floppy drives operate at a variable speed while Amiga drives maintain a constant speed. The original Apple drives and early clone drives were 'dumb' mechanisms….they were capable of variable speeds but the actual speed control was done by a special floppy controller chip in the Mac….a chip called the Incredible Woz Chip (the Amiga isn't the only computer withe 'cute' chip names!). More recent Apple and Mac clone floppy drives have the speed control built into the drive and do not need to depend on the Woz chip to rotate at the right speed depending on the position of the drive head. Amax does not emulate the Woz chip in their software hence only new drives work with it. Central Coast Software is selling a combination hardware and software product called Mac-2-Dos which allows you to hook up a Mac drive to an Amiga and to transfer files back and forth all under AmigaDos. Mac-2-Dos also provides for a full emulation of the Woz chips. They also market an 'older' style 'dumb' drive which can be held at a constant drive speed and hence can be used as both a Mac drive and an Amiga drive. This drive will also function normally on all real Macs since they contain the Woz chip. It will NOT work under Amax since as noted above Amax does not emulate the Woz chip. Apple has a new drive called the Unidrive which can read both Mac and IBM disks which must mean that it is capable of having a fixed and a variable speed. You should be able to get this drive and any third party clones of it (if there are any) to work as an Amiga drive either under Mac-2-Dos or under custom software. <continued>