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From: J Wunsch <j@ida.interface-business.de>
Message-Id: <199601091328.OAA02956@ida.interface-business.de>
Subject: Tape density&blocksize
To: freebsd-scsi@freebsd.org
Date: Tue, 9 Jan 1996 14:28:07 +0100 (MET)
Reply-To: joerg_wunsch@interface-business.de (Joerg Wunsch)
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Why is this?

        switch ((int)st->density) {
        case HALFINCH_800:
        case HALFINCH_1600:
        case HALFINCH_6250:
        case DDS:
                st->flags &= ~ST_FIXEDBLOCKS;
                st->blksiz = 0;
                SC_DEBUG(sc_link, SDEV_DB3, ("density specified variable\n"));
                goto done;
        case QIC_11:
        case QIC_24:
        case QIC_120:
        case QIC_150:
>>>     case QIC_525:
>>>     case QIC_1320:
                st->flags |= ST_FIXEDBLOCKS;
                if (st->media_blksiz > 0) {
                        st->blksiz = st->media_blksiz;
                } else {
                        st->blksiz = DEF_FIXED_BSIZE;
                }

To the best of my knowledge, QIC >= 525 is also variable-length.  Is
there any particular reason for the above?

Where could i find what a tape density code 0x92 might be?

I'm currently helping somebody to diagnose the Exabyte-2501 problems
several people have been reporting.  It looks like these are related
to density and/or blocksize probs.  (EXB-2501 is a 2-gig QIC drive,
apparently rather new, and it doesn't work right out of the box under
FreeBSD.)

-- 
J"org Wunsch					       Unix support engineer
joerg_wunsch@interface-business.de
					[private: http://www.sax.de/~joerg/]