double-density disk

Included support for single and double-density disk drives.

It was therefore possible to use a high-density drive to format a double-density disk to the higher capacity.

High-density drives could also read and write to double-density disks, allowing an upgrade path.

The Amiga disk drive officially supported tracks 0-79 from a double-density disk, but could actually read tracks 80 through 82.

When these stronger fields were written onto a double-density disk (having lower coercivity media), the strongly magnetized oxide particles would begin to affect the magnetic charge of adjacent particles.

North Star later updated the disk drive to support double-density disks with 180 kB, and later still double-sided, double-density disks with 360 kB of storage.

Codename during production: ADOS When the Atari XF551 drive came out, not only was it Atari's first drive that could read double-density disks, it was also double-sided.