#C-Ltd upgrade message
4 messages in this thread
Ron,
As with anything, the better the quality (and often price), the better the
product. Yes, there are high quality RLL drives, that are probably quite
reliable. That, however, does not say that they are _as reliable_ as the MFM
counterpart (same mechanism, etc.).
In the area of low cost drives, the difference is more noticable. Note that
these are comments of a general nature, and not specific to any given drive
(yours, Don's, mine, etc.). It is due to the more stringent requirements of the
drive if it is to handle RLL.
-larry
A question I had put to you I'd like to repeat – if you have a good enough (to
be properly reliable) rll drive of 30meg (example) and an equally available mfm
drive of the same capacity, what sort of prices would you be talking about
relative to each other? In other words, which, of either, would cost more?
BTW, in an embedded scsi drive, what method (other then mfm or rll?) is used to
encode the data?
Ron
Ron,
That's still comparing apples and oranges. Your 30 Meg RLL drive is
simply the same mechanism used in a 20 Meg MFM drive that has been designed,
tested and certified to run under RLL encoding. The controllers are obviously
different thou.
To get 30 Meg from a drive (MFM), you'd need more cylinders, or more
platters on the mechanism…thus you'd be comparing two different drives.
I can buy a card for my MS-DOS side HD that'll double it's capacity by
compressing the data (similar to what ARC does) but the drive itself still only
holds 10 Meg. Comparing that setup with a real 20 Meg drive isn't a valid
comparison.
With that said…since you insist on asking us for that comparison…
I'd GUESS the cost differnce would be in the $50 to $100 range. That would
include the cost difference between an MFM adapter and an RLL adapter.
Don
Ron,
I will give you the same answer I gave then, I don't know.
In an embedded SCSI drive, the encoding method is internal, and therefore
unknown, unless you want to take the trouble to hang an oscilloscope on it and
see what it is.
-larry