Tandy 1000 Hard Card

Tandy offered a Hard Card for it's Tandy 1000 Series of (broadly) IBM compatible PCs to provide hard drive storage. Capacities of 20 and 40MBs were offered.

Controller

Typically Western Digital 8-bit ISA controllers were used such as the Western Digital WD 61-000347, an early IDE controller designed to operate with 8-bit XT class machines.

Drives

The drives were typically of the slow stepper-motor design, such as the Western Digital WD93028-X IDE drive.

Performance

The formating utility for the cards provided by Tandy used an Interleave of 3:1, which unfortunately the controller and CPU combination could not keep up with, hence for MFM drives a full 17 revolutions were required to read a track, resulting in disk transfer rates of just 40KB/s.

By reformatting the drives with an Interleave of 4:1, sequential performance could be boosted over four times, to around 160KB/s.

See Also

• Hard Card
• Tandy
• RLL Hard Drives
• MFM Hard Drives
• IDE