Newsgroups: comp.sys.m6809
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From: consi@athena.mit.edu (Thomas R Consi)
Subject: disk drives on color computer II
Message-ID: <1991Mar21.160021.23005@athena.mit.edu>
Sender: news@athena.mit.edu (News system)
Organization: Massachusetts Institute of Technology
Distribution: usa
Date: Thu, 21 Mar 91 16:00:21 GMT
Lines: 25

I am in the process of rejuvenating my Color Computer II and I have
some questions about adding double sided double density drives:

1. I have some 360K drives from an old Leading Edge clone, they are
made by Toshiba, model # FDD5425A0N.  There is a a 9 pin jumper block
on the drive (9 pairs of pins) labeled:
	TM, L1, LD, HM, HD, D4, D3, D2, D1
Does someone know what these pins do?  The D4 to D1 pins are obviously 
the drive selects but what are the other ones?

2. I read somewhere (I think in an issue of the Rainbow) that the second
drive (/D1) should be set so the disk motor always spins even if /D0 is
selected. Is this correct and if so, why?  By experimentation I put jumpers
on pins TM, LD, HD and D2 (for drive /D1) and obtained the desired behavior.
Is this a good jumper configuration?

3. Has anybody ever ROMed OS-9 (I guess the kernal, the CMDS directory and
a BOOT file of some sort) and put the ROM in the COCO disk controller so
the machine boots to OS-9 like it currently does to the BASIC interpreter?

Any help would be appreciated.

Tom Consi


