A piece I wrote for Which Computer -- certainly not the best review I've ever written. It falls into the common error of getting too bogged down in reporting problems the reviewer encountered, without giving a proper overview of what the device is supposed to do.
I was overawed by DAT. The idea of being able to pile that much data (a gigabyte was a huge amount back in the late '80s) onto a tiny, cheap cartridge became an obsession for several years. I followed DAT through its many iterations over the following decade, and still have an HP 2GB DAT device that somehow got left behind after a review. And a lot of old DAT tapes containing, I'd imagine, fascinating historical data. I have to imagine the fascination, because without a suitable SCSI controller card and a copy of whatever proprietary software I used to make the backup, I've no prospect of ever seeing that data again.
[The GigaTape 1230][wc?][13 July 89][chb]
The first company with a practical DAT system on the open market is the German firm GigaTape, known in the US as GigaTrend. Its GigaTape 1230 is a stand-alone cream coloured box with a foot print of approximately 9 inches square, standing a little under five inches high. Versions are available for the Macintosh and IBM PC environment: the review system hooked into our CompuAdd 386-25 by means of one and a half metres of stout cable that plugged into an AT SCSI adaptor board supplied with the system. This is a full length 16-bit card built by Western Digital, using high reliability surface mount technology.
Those used to the whirr and clatter of a traditional tape backup system will find the GigaTape 1230 a mysterious box to work with. The DAT cartridge is fed in through a small letterbox above the front panel, whereupon it disappears from sight behind a flap, spirited away by an actuator. That's the last you will see or hear of the tape until you eject it again. The machine is virtually silent in use, the only indication of action being the computer screen and a four digit LCD in the front panel of GigaTape device that racks up the units of tape travel.
Beside the LCD is a row of four pressure buttons marked OnLine, Unload, Setup and Test, whose plainly labelled functions belie the fact that you will have to work in very close conjunction with the manual is you want to do anything useful with them. You will also need to turn to the documentation to discover why the button beside the cassette slot marked Eject doesn't give you your tape back. "The button marked EJECT is not operative," the manual explains helpfully.
On booting up the host computer, the BIOS in the SCSI adaptor reports "no devices are responding" -- in fact correctly, as the SCSI interface is only activated later when you load the backup software. Unfortunately there is nothing in the very skimpy photocopied A4 manual to reassure you that this "error" is correct behavior.
The GigaTape device is scheduled to appear outside the PC world bundled with a variety of backup software. But it looks as if PC users are stuck with GigaTape's own LANSAFE software, developed in house in Germany. The first version of this we received was a mess of mixed languages, but version 1.04, arriving a week before going to press, had corrected most of these problems.
LANSafe works with DOS drives and can also backup and restore Novell devices, although it wasn't able to recognise NETBIOS type device names on our Invisbile Network LAN. It is a powerful, well-structured package, but like so much backup software lacks the finesse of more widely used products, and at first glance gives the impression of an engineers' utility to which a pop-up menu front end has been attached as an afterthought. Error messages tend to be terse and are flashed up on the screen only momentarily, usually without explanation. For example, a quick glimpse of the message "Read Error" down in the left hand corner of the screen as you attempt to mount a tape might lead you to supect that something is seriously wrong with the machine, or with the quality of the media. In fact all this message meant when we encountered it was that we had forgotten to initialise the tape correctly.
GigaTape uses a format called DATA-DAT, promoted by Hitachi and others. Unlike H-P's DDS system (see Technology Report), DATA-DAT requires the tape to be pre-formatted. Normally this two-hour process is carried out by the manufacturer, but to ensure you're not trapped into a single source for your tape supply, the GigaTape system allows you to format your own tapes, either through the LANSafe software (which means your machine will be tied up for two hours) or directly through the front panel of the GigaTape device.
Two further steps are necessary before the tape can be used to store new data. First you have to create a volume, giving the tape a name by which the tape library, stored on your hard disk, will identify it in the future. Each volume is further divided into what GigaTape calls "chapters" within the volumes. A chapter corresponds to what other backup system manufacturers would call a "session", or a "dataset". By this means multiple sessions can be recorded on the same tape -- obviously on most systems the 1.2 gigabyte capacity would be wasted if you couldn't do this.
LanSafe's library is a database of all your DAT tapes, preserving the directory structure of the files you have backed up. You can restore single or multiple files by choosing them from the library, and you can inspect the database either tape by tape or file by file. This second approach assembles files of the same name from several sessions, together with their creation dates and sizes, so that you can keep track of multiple revisions.
Conclusions
The GigaTape 1230 is very fast, streaming data at a rate of over seven Mbytes a minute.
The relatively high purchase price of the device, 5,000 pounds including LANSafe software, is offset by the remarkable low cost of the media -- around
10 pounds or less per DAT cassette.
The very poorly produced software and hardware manuals are off-putting at this price, but the unit itself is handsomely produced and a joy to use.
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