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From: jdow@gryphon.CTS.COM (Joanne Dow)
Newsgroups: sci.electronics,comp.sys.amiga
Subject: Re: noKLICKstart
Message-ID: <1544@gryphon.CTS.COM>
Date: Mon, 14-Sep-87 18:25:22 EDT
Article-I.D.: gryphon.1544
Posted: Mon Sep 14 18:25:22 1987
Date-Received: Wed, 16-Sep-87 06:40:18 EDT
References: <3688@zen.berkeley.edu>
Reply-To: jdow@gryphon.CTS.COM (Joanne Dow)
Organization: Wizardess Designs
Lines: 48
Keywords: Matsuhita, Mitsumi, Sony, NEC, Chinon, Panasonic, Fujutsu
Summary: An easier way in HW?
Xref: mnetor sci.electronics:1301 comp.sys.amiga:8364

In article <3688@zen.berkeley.edu> bryce@hoser.berkeley.edu (Bryce Nesbitt) writes:
>[ Cross-posted to sci.electronics because it's about electronics,
>  though the problem showed up with the Amiga Computer. Please edit the
>  group line if your response is not approprate to both groups. ]
>[ You need to know that the 90mm disk drives of the Amiga Personal Computer
>  make a clicking noise when empty.  You also need to know that 90mm ~=
>  3.5 inches ]
>
>Recently I posted a Kickstart patch to turn 1.2 Kickstart into 1.2
>noKLICKstart.  I know it was popular because hundreds of people
>responeded (Email and otherwise).  Sadly, many of those 
>complained that it did not stop the click of *their* drives.  What
>follows is a technical desciption of what goes on and how to fix
>it:

>all the drives that do, *already work fine*.  If you want to get a non
>working drive to work you would need to either:
>
>A> Cut /STEP on the drive PCB so it gets to the latch, but not the stepper
>motor.  Now add a gate that will disallow /STEP if the track zero sensor
>is active and the direction is out.
>
>B> Tap the change sensor on the board and drag it external.  Use /STEP to
>reset your external latch (ignore the internal one).  Now add the circuit
>to disable /STEP when track zero is active and the direction is out.
>
>Both are simple, but painful to do.  I don't expect that anyone will try
>them.
>

Er, there may well be a better way. If you're going to hack at the drive why 
not tell the fool thing to not step the head unless the head is loaded? The
clicks come with the head unloaded. Hence going in and adding a gate to 
intercept the head step pulses unless the head is loaded should do the trick
admirably.

Hm, maybe my hardware background is showing here... SW weenies shouldn't
know this kinda stuff, nie?     <^_->


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