[geeks] The new IPC/LX, from Dell?

[Jochen Kunz]

On Fri, 20 Nov 2009 08:25:45 -0500
Lionel Peterson <lionel4287 at gmail.com> wrote:

> As I recall, IDE was all about cheap drives, and reducing the silicon
> on the actual drive is how they did it.
The oposite. They put the ST-506 MFM / RLL drive controller on the
drive itself. This increased the electronics on the drive and most
likely made the drive more expensive. But you didn't need an exrta
controller anymore. The "controller" was reduced to a small logic for
bus address decoding and a bus driver. This "controller" routed most of
the ISA bus directely to the drive and was very cheap. The actual
controller on the drive is cheaper than the MFM / RLL controller also.
A MFM / RLL must work with many different dirves. The controller in an
IDE drive needs to work with exactely one drive and can be optimized
(in cost) to this drive. Due to this optimazion and avoiding the MFM /
RLL interface you could also increase data density and speed. I.e. you
need a smaler drive with less heads to get the same capacity. Yet more
cost reduction...
--


tsch|_,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/