Re: Amiga 500

From: Ethan Dicks <ethan.dicks_at_gmail.com>
Date: Mon, 2 May 2011 18:18:04 -0400
Message-ID: <BANLkTi=tN17sEPTAGGijxjpemrKi7v8KMg@mail.gmail.com>
On Mon, May 2, 2011 at 5:33 PM, Anders Carlsson <anders.carlsson@sfks.se> wrote:
> Scott wrote:
>
>> Also, the disk drive continually runs or clicks

That's "normal" - the machine is stepping the drive to set/reset the
/DSKCHG signal when the user changes media (something that DOS PCs
don't do and don't know about).  There were a number of "no click"
hacks back in the day (which IIRC relied on the drive not stepping
below track zero, so the internal drive electronics still checked the
media-inserted switches but didn't actually move the heads).

> You should be aware that Amiga floppy drives tend to be the first item
> to break. There are a lot of Amigas out there which work except for the
> built-in floppy drive. The mechanism is the same Chinon F?-354 type as
> found in e.g. Atari ST and some other computers. Supposedly the way the
> Amiga accesses the floppy drive would shorten its life.

I've owned a lot of Amigas over the years and I don't recall a higher
floppy drive mortality rate than PC or Mac hardware of the same era,
but perhaps so few Amiga 500s had hard drives that they simply racked
up more hours on the floppy drives than other types of machines and
the drives wore out.  There's nothing intrinsically "wrong" with the
way Amigas access the floppy drive (they achieve greater storage
density by writing out whole tracks at a time vs writing out
individual sectors one by one, so they can skimp on the inter-sector
gaps enough to add up to a couple more sectors per track).

> The fact that the drive reads for a few seconds then fails tells me you
> might as well try to get another drive as another floppy disk. In theory
> I think a standard PC drive would work after a few modifications, mainly
> emulating the disk change signal but I never went through with doing it
> myself.

http://dliapp.wizhut.com/blog/?p=59
http://www.flickr.com/photos/tbl/4068073847/

-ethan

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Received on 2011-05-02 23:00:12

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