Who USB'ed the Firewire on IrDA?

September 1, 1999

Dear Squeak and Blat,

OK, I'm really frustrated. I just bought one of those new Macs with the fancy color scheme that reminds me of a set of pool toys I bought last summer. The machine runs beautifully and I am getting use to the new mouse and keyboard, but I looked for a place to plug in my printer and MIDI interface and couldn't do it. A friend of mine told me that I need a new MIDI interface that uses USB technology. He also said something about FireWire. What is this all about.

Signed, Dr. I. M. Upset 



Dear Dr. Upset:

Relax, relax. Both USB (Universal Serial Bus) and FireWire are really exciting innovations for Macs. They are also becoming standard on Wintel machines too, so this is not just a Mac thing. Both of these features have to do with new ways for peripheral devices to link to your computer. On the Mac side, USB replaces the traditional 8-pin serial port that has been standard for years. FireWire replaces the traditional SCSI (small computer system interface) port. Each of these new approaches to connecting things to your computer offers two distinct advantages: speed and flexibility. More about this in a moment.

The USB development has really thrown musicians for a loop because the new USB compatible MIDI interfaces have been slow in reaching the market. Folks like you have had to scramble to continue to be productive musically. As I write these words, the interfaces are just arriving in stores near me in Chicago so I assume that you should be in good shape when you read this. I will let Squeak deal with some of the options that you have on the USB side and some of the more technical aspects. I will help you with FireWire.

USB is much faster than the older 8-pin serial connection for the Mac (as Squeak will surely describe) and FireWire (technically called IEEE-1394 High Performance Serial Bus) really blows SCSI out of the water. SCSI works at 40 Mbps (megabits per second) as opposed to FireWire that screams at up to 400 Mbps. This is fast enough to transfer digital video and audio in real time! In fact, some of the very first computer peripherals to emerge that use FireWire are video cameras (see links listed below). Another category of devices that are now reaching the market are external hard drives that this technology. These drives are quite portable and can be carried from home to work or used as effective external hard drives for notebook computers. (The current crop of laptop computers typically do not have FireWire built in but do support PCMCIA cards that are devoted to the FireWire interface.)

FireWire products are appearing each week. Many of the devices are on the high end of the price range (especially the cameras), but this will change as time goes on.

Besides speed, FireWire does away with the SCSI chain termination problems and the setting of SCSI numbers. Up to 63 devices (16 can be daisy chained together) can be supported with little work about order.


Hey I.M. Don't be upset or confused. USB and Firewire are great notions. So are infrared ports too for that matter. In fact, the several members of the computing industry got together several years ago and plotted this development over several years to insure that a smooth migration is made from the days of SCSI, parallel, and serial ports (with many varieties of dreaded connectors for which you never had the right combination), to the day when the back of your computer will only have a power plug, USB, and Firewire ports (and probably an infra red port as well). Let me elaborate on some of Blat's well informed comments and clear up a few places where his chewing tobacco missed the old spittoon (trumpet players can get away with this, when clarinet players wouldn't dare….)

For plain-vanilla computing (sans video and audio), USB is your main concern. As Blat noted, with one common cable-and-plug, you can connect up printers, MIDI interfaces, modems, NICS or network interface cards (like Ethernet), scanners, Zip drives, digital video cameras, CD-RW drives, keyboards, mice, and the list goes on for more devices than you can imagine. You will need to manage connecting a number of these devices with USB hubs. Below is a diagram of a series of USB devices connected with a hub in a star configuration. (Graphic from www.aten-usa.com)

If you want a generous sampling of what peripherals are going to USB connectivity check out the allUSB web site: http://www.allUSB.com. The image on the left shows what a USB connector looks like.

Now for Firewire. You mainly will concern yourself with this interface technology when you want to do heavy duty, ultra high speed stuff. As Blat noted, it also goes by the more technical name of IEEE 1394. To confuse matters more, Sony calls the connector the "iLink" on its digital cameras. It is the same thing.

The first devices to use Firewire are digital video cameras where you need to shove a bit-load of video data between the camera and the computer in a hurry. Digital audio applications will come along soon as well. You are going to be able to feed digital audio fast enough over Firewire to play music in real time as it streams off a hard drive without your computer missing a beat in the music.

The speed of the USBs and Firewire is fast; faster than even Blat's figures when the specification is fully implemented. (Check out the discussion of these interface standards in the 2nd edition of our EMT textbook.). Here's a great table from the Adaptec web site that nicely compares the differences. Basically, Firewire in its currently implementation, is 16 times faster than USB. Potentially, it can go as high as 80 times as fast (that's over 1 GBPS, and the G doesn't stand for a circus gallop!)



Maximum Number Of Devices 62 127
Hot-Swap (Add Or Remove Devices Without Rebooting Computer) Yes Yes
Maximum Cable Length Between Devices 4.5m 5m (about 16 feet!)
Data Transfer Rate 200mbps (25MB/sec) 12mbps (1.5MB/sec)
Bandwidth Roadmap 400mbps (50MB/sec)
800mbps (100MB/sec)
1Gbps+ (125MB/sec+) None
Peripheral Devices DV Camcorders
High-Resolution Digital Cameras
Set-Top Boxes
Hard Disks
DVD-ROM Drives
Scanners Keyboards
Low-Resolution Digital Cameras
Low-Speed CD-ROM

Any downside to the magic of USB and Firewire? Yes! We haven't eliminated the spaghetti of wires that will accumulate off the back of your computer. Enough USB devices networked off the back of your computer and your computer workstation will look like a rattlesnake pit at the Okeene, Oklahoma rattlesnake hunt. Fortunately, not as dangerous.

The great thing about connecting and disconnecting these things is your don't have to turn the computer off every time you want to plug or unplug something as you did in the days of SCSI connectors. This is called "hot swapping" connections. Also, the wires are small and flexible. Just about any computer you buy these days will have USB and Firewire ports; that's the grand industry plan. In another year, the serial, parallel, and SCSI stuff will start disappearing completely.

What about infrared? This is also known as IrDA ports. This is one solution to the snakepit-of-wires hassle. I had this infrared port on my Dell laptop for over a year and never used it. Then I purchased a little color ink-jet printer to take with me on the road and it had infra red built into it. When I got this to working it was pretty slick. Look Ma, no wires! You just have to line things up so that the device's infra red ports are in sight of one another. The transfer rates for IrDA is equivalent to the speed of most things you could connect to a parallel port on a computer. This is the same technology used for your remote controls for TV, video players, and the like. You can even purchase an IrDA add-on hub for your computer if you don't already have one built in.

Gee, I wonder if you can do MIDI over IrDA? We could be throwing wireless, infrared MIDI music at each other across the room!

Well that's my 2 cents, Dr. Upset, on USB, Firewire, and, one more, IrDA, wireless connectivity from your computer workstation. I've got to hot swap my computer for my clarinet. My polka band, the USB Meisters, is doing a gig at the national Firewire hunt in Sapalupa!

2201 Last modified on December 19, 2013
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