Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ukma!gatech!ncsuvx!mcnc!rti!sunpix!matthew
From: matthew@sunpix.UUCP ( Sun NCAA)
Newsgroups: comp.sys.apple
Subject: Re: Disk ][, Apple //c, HELP!!
Message-ID: <604@greens.UUCP>
Date: 1 May 89 15:38:17 GMT
References: <890430153927.040595@UNCAMULT.BITNET>
Organization: Sun Microsystems, Research Triangle Park, NC
Lines: 34

In article <890430153927.040595@UNCAMULT.BITNET>, CYLau@UNCAMULT.BITNET writes:
> 
>  Help!!  My //c is acting up..  The stupid machine won't shut off the
> drive..  it will read and write properly but not shut the drive off when
> it's finished..  I suspect the IWM chip, but I'm not absolutely sure.

If your problem was on an older Disk ][ controller card I'd say the problem 
was the 555 timer on the card that keep the drives spinning for a second or
two after being turned off (keeps the drive spinning during very short off time
to reduce startup time if your software makes a lot of quick accesses).  A look
at the Apple //c schematics show that the Apple //c drives are controlled from
the IWM, so I assume this function of the Disk ][ controller was also incorporated
into the IWM

> Also, is it possible, if the problem is the IWM, to get a new one ANYWHERE??

IWM are available from a few sources selling Apple original parts. I believe 
the selling price of a IWM is $29.  Computer Shopper is your needed source of info 

> I tested it on my //c (before I blew the IWM) and it kept running until I put 
> a disk in the drive, then it said "Check Disk"...  I wasn't aware that an ext.  
> drive was supposed to do that..  my internal doesn't do that...  

I've never heard of an external drive doing that either, but your internal drive
is suppose to do that after a number of retries at reading track 0/sector 0.
turn on your //c without any disks in any drive. You'll see what I mean.



-- 
Matthew Lee Stier                         |
Sun Microsystems ---  RTP, NC  27709-3447 |        "Wisconsin   Escapee"
uucp: { sun, mcnc!rti }!sunpix!matthew    |
phone: (919) 469-8300 fax: (919) 460-8355 |