3 ms·
The original Mac floppy also was constant linear velocity (https://en.wikipedia.org/wiki/Constant_linear_velocity https://en.wikipedia.org/wiki/Constant_linear_
by Someone 1y ago
The original Mac floppy also was constant linear velocity (https://en.wikipedia.org/wiki/Constant_linear_velocity https://en.wikipedia.org/wiki/Constant_linear_velocity), with rotation speed being under software control.
http://www.mac.linux-m68k.org/devel/plushw.php http://www.mac.linux-m68k.org/devel/plushw.php:
“The Macintosh disk interface uses a design similar to that used on the Apple
II and Apple III computers, employing the Apple custom IWM chip. Another
custom chip called the Analog Signal Generator (ASG) reads the disk speed
buffer in RAM and generates voltages that control the disk speed. Together
with the VIA, the IWM and the ASG generate all the signals necessary to
read, write, format, and eject the 3 1/2-inch disks used by the Macintosh.”