Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!mit-eddie!media-lab.media.mit.edu!masaru
From: masaru@media-lab.media.mit.edu.MEDIA.MIT.EDU (Masaru Sugai)
Newsgroups: comp.sys.amiga.hardware
Subject: A3090 tape driver ??(Re: BTN 2.0 Tape handler)
Summary: TAR+BTN won't work with A3090!
Keywords: TAR, BTN, A3000, A3090
Message-ID: <5692@media-lab.media.mit.edu.MEDIA.MIT.EDU>
Date: 22 Apr 91 03:51:05 GMT
References: <1991Apr13.014520.13657@sugar.hackercorp.com> <61897@masscomp.westford.ccur.com>
Reply-To: masaru@media-lab.media.mit.edu (Masaru Sugai)
Organization: MIT Media Lab, Cambridge MA
Lines: 58

In article <61897@masscomp.westford.ccur.com> mark@calvin.westford.ccur.com (Mark Thompson) writes:
>In article <1991Apr13.014520.13657@sugar.hackercorp.com> ssd@sugar.hackercorp.com (Scott Denham) writes:
>>Does anyone recognize these symptoms?  
>> I'm running BTNTape 2.0 on an A2000 / A2090A to a Cipher 540 1/4" tape
>>drive. I can get TAR to read from the drive, but after some
>>(variable) number of blocks are read, the system locks up solid.
>
>Yes, I have seen the same thing. I was using BTNTape 2.0 with a 525 Meg
>Archive 1/4" tape drive in a 2500/30 with a 2091. When I ran with the
>default handler setups, it would take a while to lock, but when it was
>optimized for speed with my drive, lockup would occur quite quickly.
>I hope someone can answer how to fix this since the new BTN is about 4x
>faster than BRU with my configuration and I desparately need FAST archiving.

I third them :)

I've been frustrated with my A3090 (C= 150MB QIC) I picked up yesterday. 
I hooked it up to A3000/16, and was easy to take a full backup of WORK: 
using BRU w/o any problems.  All I had to do were moving tape: entry
to the top of BRUtab file, then "bru -c" at the root directory. That's it.

Encouraged with this success, I then tried TAR+MWtape from fish #440s, and
it ruined my Saturday night!  I had to check several FTP sites, CIS, and BIX
to get ARP mount command which MWtape requires, but no avail.

I gave up MWtape and went to BTN.  BTN seems quite useful, especially its
tapemon tool is wonderful as it shows what's going on in tape drives.
But there are several glitches.

  - I could store and restore files only when I set tape buffer to 512B long.
    Buuut, it's slow (say, 15KB/sec) and consumes most of tape for block gaps!
    Nearly 80% of tape has used to just save 30MB.

  - With buffer size over 1024B or more, TAR seems to write all data on tape.
    Archiving speed is around 90KB/sec when I set buffer size to 64KB, 
    acceptable performance, judging from A3090 transfer rate (112.5KB/sec).
    This is an option for a write-only mode, though.  I can read, say, first
    megs, but as soon as I hit upon a large file (a few hudred kilobytes),
    TAR quits with Tapemon's "SELECTION TIMEOUT ERROR" message.  I am better
    off than they are, as I am free from lockup and guru SO FAR.
    
I know what BTN stands for, but it is a decent implementation of tape 
driver on standard Amiga configuration. It would be a BTA with a little
bit more of error handling... Any idea ?

BTW, does anybody have working experience of TAR to exchange data with UNIX ?
I have no idea what is the most appropriate block size, as A3090 has nothing
technical on its booklet. Is there any preferred block size for each UNIX ?

Finally to A3090 owners: what are 'buttons' stapled on the installation
guide for ? Are they edible ?

-- Masaru Sugai

-- 
-- Masaru Sugai:Use disclaimer. CIS 72050,2141:NeXT + A3000 = money-eater
NEC Corporation:sugai@ccs.mt.nec.co.jp DORMANT:hardwired logic,machine language
MIT R.Affiliate:masaru@media-lab.media.mit.edu:  "Silicon on Sapphire" by CLASH