Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sdd.hp.com!hp-pcd!hplsla!tomb
From: tomb@hplsla.HP.COM (Tom Bruhns)
Newsgroups: comp.sys.amiga.misc
Subject: Re: Adding an IBM type 3.5" High Density Drive to Amiga
Message-ID: <18730003@hplsla.HP.COM>
Date: 3 Jun 91 20:08:58 GMT
References: <1991May7.002625.1696@tplrd.tpl.oz.au>
Organization: HP Lake Stevens, WA
Lines: 33

cmcmanis@stpeter.Eng.Sun.COM (Chuck McManis) writes:

> When, in fact, to get them into "high density" mode you have to
> redesign the floppy interface including new drivers, a memory/bus
> interface, etc. And yet no one to date has ever posted a question
> like yours and followed it up with exactly what it takes to do it.

So what's wrong with posting to find out if anyone has indeed done
it before (or maybe even just given it some serious thought)?  Not
everyone posts about each and every success, and even if they did,
I wouldn't have time to read them all, and I don't have a good
enough memory to remember them all.

Also, why assume that "new drivers, a memory/bus interface, etc."
are required?  If the HD floppy external electronics makes it
look like a standard 1-meg floppy (same data rate and format), but
with more tracks, would the Amiga care (given the apropriate mountlist
entry)?  If I built a solid-state external 'floppy', would the Amiga
OS even care how many tracks it had?

BTW, a good source of floppy info from 'the old days' is some issues of
Pertec's "Peripheral Review."  I wrote a white paper for one of my 
classes (long ago) on feasibility of a certain floppy interface, and
data from Byte's articles and from floppy drive manufacturers could 
not have let me make the case I did; the short Peripheral Review 
articles were packed with useful data on what really goes on in a 
floppy interface.  I think they've been out of business for some time,
but some old-timer (1970's ;-) may have copies.  (These were little 
4-8 page newsletters published occasionally...some sales articles and
some technical)

PS:  Why would someone designing an interface to a stock floppy drive
care about the flux density at the medium?