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USB—IT'S NOT JUST A BUS, IT'S AN ADVENTURE

by Tom Cantrell

Start ı Nearvana ı Waiting for Baudot ı Not So Fast ı VolksPort ı Going Mobile ı Sources and PDF

Itıs all too easy to become hard-hearted and cynical when it comes to PCs. You would think buying a new computer or some snazzy software or hardware upgrade would be fun. Instead, itıs something I contemplate only when thereıs no other way out. Computersıcanıt live with them, canıt live without them.

Writing stories, developing embedded code, communicating over a modem, I was doing those things 25 years ago. It seems like the only difference is that megahertz, kilobytes, and megabytes turned into gigahertz, megabytes, and gigabytes, with seemingly little more than a bunch of eye candy to show for it. Now, thereıs C, C++, and Java instead of ASM, BASIC, and Pascal. Oh, the joy!

Fussing with RS-232 and Centronics ports? I was doing that, too.

Plug in some strange piece of hardware, have the OS automatically detect and report that fact, and nicely help with the details of getting it installed, now thatıs worth writing home about. Yes, Iım talking about USB, one of the few things about PCs that brings a smile to my face. Maybe Iıve just been lucky, but Iıve had nothing but good experiences with USB. Just plug it in and it works.

Compared to serial ports, USB is a dream come true. No more fussing with gender changers, nine to 25 pin adapters, DTE/DCE mix-ups, software settings, IRQ overloads, and handshaking foibles. I estimate that the effort spent grappling with such over the years exceeds the GNP of many well-developed countries. And, just what dollar value do you put on premature gray hair?

Donıt think Iım letting the parallel port off the hook. Things were OK way back when a printer port was just that, but it wasnıt long before folks couldnıt leave well enough alone.

Desperate for a place to plug-in without going under the hood (i.e., internal slots), impetuous designers soon hijacked the printer port for disk drives, scanners, EPROM programmers, emulators, and just about anything else with an electron moving in it. The infamous bidirectional hack, using printer status lines like "out of paper" for a back channel, was just the ignominious start. Too far along the primrose path, the IEEE stepped in to try to bring some order to the chaos, but even they werenıt up to the task.

Today, things seem so messed up youıre lucky if you can get a printer to work. Awhile back, I spent about $300 worth of my time trying to get a parallel port inkjet printer linked properly before I wised up and just bought a new $100 USB inkjet.

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