Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!crdgw1!rpi!sci.ccny.cuny.edu!jeffrey
From: jeffrey@sci.ccny.cuny.edu (Jeffrey L Bromberger)
Newsgroups: comp.sys.3b1
Subject: Re: "Floppy tape"
Keywords: segment size, standalone boot
Message-ID: <1991Feb18.162005.15219@sci.ccny.cuny.edu>
Date: 18 Feb 91 16:20:05 GMT
References: <72@fbits.ttank.com>
Organization: City College of New York - Science Computing Facility
Lines: 39

In article <72@fbits.ttank.com> Mariusz@fbits.ttank.com (Mariusz Stanczak) writes:
>Having recently accuired a tape backup unit (thanks Vince),
>I have the following quiestions:
>
>	- has anyone created a standalone boot floppy with
>	  a configuration that would permit the use of the
>	  tape unit?  What would that entail if I were to
>	  create one?
Look on OSU - Lenny posted something like this, using the .o's for the
kernel and the tp driver, you made a bootable floppy.

>	- even with large blocking (256KB is the largest
>	  I could enter to `gtar') the unit does not seem
>	  to "stream" for long... it's runs more like a saw,
>	  forth and back.  Is that it's "beauty"?  This be-
>	  havior makes it VERY slow (though I appreciate 
>	  having the ability to "compress"-backup the whole
>	  44MB on one cart :-)).  Any work-arounds (`dbuf'
>	  does help some, but not enough)?
I was working on this for a while, but gave up in disgust.  There was
*no* documentation on the driver interface!  Even with a little help
from some friends, it was still pretty ugly.  There was no
*distributed* tp.h file, and the man page for qt(7) is positively not
what we have - there were no working QIC-02 boards for the general
public.

What probably has to be done is to make a diffent kind of dbuf (maybe
tbuf?) that stores huge data chunks.  If you can push enough
data at the tape, you can get about a 6.5 second stream, the most I
ever saw :-(  If anyone ever managed to get it to really stream, I'd
be delighted to hear how!!

j

-- 
Jeffrey L. Bromberger
System Operator---City College of New York---Science Computing Facility
jeffrey@sci.ccny.cuny.edu			jeffrey@ccnysci.BITNET
	Anywhere!{cmcl2,philabs,phri}!ccnysci!jeffrey