Re: transfer from Explorer to Symbolics

[Doug Evans <DE%phoenix.sch.symbolics.com@RELAY.CS.NET>]

    Date: Thu, 23 Mar 89 13:18:30 pst
    From: snicoud@atc.boeing.com (Stephen Nicoud)

        Date: Thu Mar 23 12:32:34 PST 1989
        From: DE@PHOENIX.SCH.Symbolics.COM (Doug Evans)
        Subject: transfer from explorer to Symbolics

        6250 didn't work as density can only be specified for reel-to-reel
        tapes.  Density for cart tapes on all Lisp Machines is fixed (by the
        type of tape drive) at 8000 ftpi.

    Is this true?  I have successfully restored files put on tape by an
    Explorer using the Carry Tape mode (6250 density) from a 3670.  I used
    the READ CARRY TAPE command.  It prompted me for :DENSITY and :DEVICE
    (among other things).  I gave it 6250 and CART respectively, and it
    merrily restored the files from the tape.

The value for the :density keyword is ignored by the software when
:device cart is used.  Different specified densities for device cart
should have no effect on the written format or density of a cart tape as
those attributes are preset physically on the cart tape drive.

Just to make sure I don't have both feet in my mouth, I did a search
thru the cart tape software:
	sys:lmtape;fep-tape.lisp
	sys:lmtape;cart-tape.lisp
	sys:lmtape;nbs-cart.lisp 
and I found no reference to use of the :density keyword hidden in the
software.  The :density keyword is used in other files (almost every
other one in the directory) for when a reel-to-reel tape drive is used.
FYI, our software (with all patches loaded) supports 1600/3200/6250
densities for reel-to-reel tape drives.

I'm confused here with what you're reporting.  Did you specify 6250 on
the Symbolics, the Explorer, or both.  As I said, on the 3670, density
values are ignored and have no effect for cart tapes.  Every QIC-02
interface cart tape drive we have used or evaluated has fixed density at
8000ftpi.  On the Explorer, I can't say.  Maybe TI Technical Support can
throw some light on what happens in their machines.

    I certainly didn't have to put jumpers across any pins.

This probably means that in either your case or in Mr. Baechler's case,
the Explorer's or the 3670's cart tape drive might have been setup
wrong. 

    Steve Nicoud	ARPA: <snicoud@atc.boeing.com>