[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: machine doesn't know it has a tape drive



    Date: Wed, 29 May 91 14:01 MDT
    From: paul@taos.intel.com (Paul Collier)
  
	    >You might try flipping the wide ribbon cable connector 180 degrees -
	    >having
	    >it on backwards will cause the machine to think there is no tape
	    >drive,
	    >and might also cause the indicator to light when the machine is
	    >simply
	    >trying to access the drive.
	
    I would be most hesitant to try this. You could well smoke your drive;
    besides most ribbon connectors are keyed so as to make it very difficult
    to put them on incorrectly. 

I wish this were the case, but the older Cypher tape drives on Symbolics
machines do not have keyed cable connectors and are easily plugged in the
"wrong" way at either end.  This does no harm to the hardware, but does
cause the machine to think that no drive is in place - unless you reverse
the connection at both ends.  I speak from experience, not conjecture.

I have also used a newer portable cartridge tape drive which had no
keying, and connecting it backwards did not damage anything.

If you connect a power cable the wrong way, however, I'm sure bad things
will happen.  I have never seen a power cable connector on a Symbolics
machine that can be treated this way.  They're not just keyed, they're
shaped so that they will only fit one way.