Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!rpi!sci.ccny.cuny.edu!phri!cooper!mayer
From: mayer@cooper.cooper.EDU (Mayer Ilovitz )
Newsgroups: comp.sys.ncr
Subject: Copying from tape and byte swapping
Message-ID: <2053@cooper.cooper.EDU>
Date: 19 Jan 90 00:34:36 GMT
Organization: The Cooper Union (NY, NY)
Lines: 27

Hi,

	The SCSI tape controllers used on our Tower 650 has a register
that determines whether or not the bytes are swapped by the controller.
By changing the value of this register you can avoid having to do a
dd conv=swab.  In Release 2.01.00 there is an undocumented command which can
change this register's value. The command is

	/menu/obj/mtswap.o TAPEDEVICE -set VALUE

	TAPEDEVICE is the device name of your tape drive
	VALUE is:	0	for no swapping
			256	for swapping

There are two restrictions to this command; you must be root to execute it and
you must have a tape in the drive for the command to work.

On our system, the 150M drive is set to swab and the 45M drive is set to
no swab.

						Mayer Ilovitz

						mayer@cooper.cooper.edu
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