Whitney Head

A successor to the original Winchester read/write head design. The primary change was to make the flexure smaller and more rigid. First used in IBM 3370/3380.

 

Whitney Technology

A method of constructing a read/write head in a rigid disk drive using a Whitney head. In all other details it is the same as Winchester technology.

 

Winchester Drive

Originally meant to signify that the drive used Winchester technology, but many times it is used to mean it is a fixed disk drive, implementing either Winchester or Whitney technology and non-removable disks sealed in a contaminant-free housing.

 

Winchester Head

The read/write head used in Winchester technology, non-removable media disk drives. May be either a monolithic or composite type. It is aerodynamically designed to fly within microinches of the disk surface.

 

Winchester Technology

A method of constructing a rigid disk drive using concepts introduced in the IBM model 3340 disk drive. The primary changes from prior art technology was to lower the mass of the slider, use of a monolithic slider, radically changing the design of the flexure and having the slider come to rest on a lubricated disk surface when disk rotation ceases. In addition to the above, a totally sealed chamber containing the read/write heads and disks was used to protect against contamination.

 

Window Margin

The amount of tolerance a read/write system has for Transition Jitter at a specified error rate level.

 

Word

A number of bits, typically a multiple of eight, processed in parallel (in a single operation). Standard word lengths are 8, 16, 32, and 64 bits (1, 2, 4, or 8 bytes).

 

Write

The recording of flux reversals on a magnetic media.

 

Write Cache Stacking

Write cache mode accepts the host write data into the buffer until the buffer is full or the host transfer is complete. A command complete interrupt is generated at the end of the transfer. A disk write task begins to store the host data to disk. Host write commands continue to be accepted and data transferred to the buffer until either the write command stack is full or the data buffer is full. The drive may reorder write commands to optimize drive throughput.

 

Write Gate Signal

A digital input signal level which causes the drive circuitry to record data.

 

Write Pre-Compensation or WPC

The intentional time shifting of write data to offset the effects of bit shift in magnetic recording. This is technology that was used on old MFM and RLL drives but is not needed with IDE drives. This setting is usually set to 0. Some systems with "Auto Detect" set this to 65.535, this is fine also. It doesn't matter what it is set to, the system ignores it.