Path: utzoo!attcan!uunet!portal!cup.portal.com!oliver From: oliver@cup.portal.com Newsgroups: sci.electronics Subject: Hard disk Ctrl Query!!!!!! Message-ID: <6490@cup.portal.com> Date: 14 Jun 88 06:21:54 GMT Organization: The Portal System (TM) Lines: 22 XPortal-User-Id: 1.1001.3624 I have an IBM AT clone....12Mhz 0 wait...and such... I run SCO Xenix with 2-130 meg Priam drives. What I want to do is add a third disk!!!!! I have had no luck in locating a MFM 3+ drive controller! I know there must be one avaible..or a way of configuring a second controller to accept disks 2 and 3... I want the third to be partioned DOS.... If there are no controllers avaible for 3+ how about this.. Cabeling 2 drive ones....i.e. same drive select/data/controll lines.... and have a 2 way toggle switch for the power between the drives????? i.e. only one would recieve the 12,5 volts at once..... Would this cause a problem with the operation of the other drive???? If so is there a way I could build a switch to connect the data/ctrl lines between the drives.....Some sort of swichable buffer device????? I do not know if some of the pins are bi-directional High speed...... Any help or schematics on my questions would be GREATLY APPRECIATED!!!!!! Oliver@cup.portal.com