Spotlight: Adaptec USBXchange

If you want to move drives or devices between machines and are unwilling to open your PC to add a SCSI card, Adaptec may have the...

If you want to move drives or devices between machines and are unwilling to open your PC to add a SCSI card, Adaptec may have the answer. Its USBXchange allows you to connect SCSI peripherals to non SCSI PCs or Macs

It's been some time since manufacturers began trying to convince us of the benefits of USB connection for peripheral devices. Indeed, it's got a lot to offer - the interface is built into almost every new PC and supported natively by all current versions of Windows and MacOS. In addition, the convenience of an external connection is really boosted by the fact that USB devices, no matter what they are, are hot swappable - you can move drives and scanners from machine to machine without having to reboot.

On the downside, although USB is all very well, it's less than convenient if you already have an investment in legacy devices - printers, Jaz drives and the like - which use more conventional devices such as SCSI or the parallel port. It's at this niche market that Adaptec is aiming its USBXchange.

Like its forerunner, the USB Connect 2000, USBXchange is a soap-on-a-rope type device. At one end there's a USB plug, at the other there's a 50-pin SCSI connector. In the box, you'll also find a disk of drivers and a 50-25 pin SCSI converter. Armed with all of these, you're ready to plug a SCSI device into your PC's USB port.

And, well, it simply works. Under Windows 2000, 98 and ME, the combination of Plug and Play and a driver CD-ROM had the USBXchange recognised and installed within a couple of minutes. That done, our machine was equipped with a SCSI port without us having to open the case - a real convenience for technophobes.

The USBXchange will also run under MacOS. However, here it's worth noting that the adaptor will only support one SCSI device (a limitation which also applies under Windows 2000). What's more, if you want to use both a mass storage device (a CD-ROM, Jaz drive or similar) and another type of peripheral (perhaps a scanner or a tape drive) on your Macintosh, you will have to manually switch modes on the adaptor. This necessitates a reboot, removing much of the convenience that should be offered by the USBXchange.

For those not running MacOS or Windows 2000, however, it should be difficult to find fault with the USBXchange. As long as you're using Windows 98 or ME, you can connect up to seven SCSI devices, although Adaptec suggests you will achieve best performance with no more than two hooked up. At 1.5Mbps, data transfer speeds are adequate, but reflect the limitations of the USB interface.

Realistically, for best performance, it is better to use a true SCSI connection rather than an emulator like this Adaptec offering. But it remains a convenient solution if you are unwilling or unable to open your PC to add a SCSI card, or need to use a SCSI device on several different PCs.

USBXchange is more flexible than its predecessor. The USB Connect 2000 drew its power from the SCSI bus, requiring a SCSI device with powered termination - this ruled out Zip drives among others. But the USBXchange can use the SCSI termination power, or run from the USB connection if you have a powered hub, or use its own optional AC adaptor. For convenience, neatness and ease of use it is a fine - and reasonably priced - option.

John Sabine

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