Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!tut.cis.ohio-state.edu!purdue!decwrl!shlump.nac.dec.com!enginr.dec.com!landry
From: landry@enginr.dec.com
Newsgroups: comp.sys.atari.st
Subject: media change problem with Toshiba drive
Message-ID: <7193@shlump.nac.dec.com>
Date: 4 Jan 90 04:35:17 GMT
Sender: newsdaemon@shlump.nac.dec.com
Organization: Digital Equipment Corporation
Lines: 30




	I read most of the messages on using generic drives with the ST and
	didn't expect any problems but . . .

	I'm adding a Toshiba ND-352TH-A also known as FDD4216G0D as a
	second floppy.  If I leave the media change diode 
	(pin 34 ---|<|--- pin 28) out, everything works fine, except of 
	course media change is not detected.  With the diode, once the disk 
	is removed once it always appears write protected.

	So I looked at the signals (only have a logic probe at home - but
	it's a good one :-)  ).  The "no media change" condition is 
	indicated by a "high" on pin 34 (jumper selected for this function)
	all the time.  "Media change" is indicated by that pin toggling
	with no drive select or constant low when the drive is selected.
	It seems that the only way I can get "no media change" is to
	power up the new drive with a disk inserted AND then reboot the ST.
	Once the disk is removed once, "media change" is always indicated.

	So, my questions are:
		1) What is the media change signal really supposed to do?
	    	   I guess that really is, what does Atari expect it to do?
		2) What is supposed to reset it from the "media change"
		   condition?
		3) Is it possible to use this drive with the ST?

	thanks
	chris