Mitsubishi Electric Apricot LS Pro, Hardware Technical Reference

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Chapter 4
Chapter 6
Chapter 4
Peripheral items
Appendix A
Appendix C
Pr
eface
Chapter 4
LS PRO HARDWARE TECHNICAL REFERENCE 4/13
Warning
Do not attempt to perform a low level format on a ProDrive, this can only adversely affect
the performance of your drive. If you do try to format your drive most standard low level
formatting programs will return a “Drive formatted” message very quickly. In fact, the drive
has not been formatted.
Discache The ProDrive LPS 240AT drive is fitted with 256kbytes of RAM and look-ahead cache
circuitry known as Discache.
When a read access is made to the drive, Discache loads subsequent data into the RAM.
If an attempt is made to read this data it is accessed from RAM rather than from the
disk, thus considerably reducing access times.
Cache performance benefits tend to be application dependent. Discache has a number
of alterable parameters which allow the cache to be configured for maximum
performance benefit in any given application.
Full information on configuring Discache is given in the Quantum specification.
Quantum LPS525A
The 525 Mbyte hard disk drive that may be fitted in the LS Pro range is a Quantum
LPS525A. It has a nominal access time of 10mS and can transfer data at up to 5 Mbytes
per second.
The drive circuit board contains the drive control electronics and a hard disk
controller. The drive features an on-board media defect and error recovery scheme
which is fully user transparent.
Jumpers Three jumpers on the drive circuit are used to configure the drive. These are shown
in the following illustration.