Humble Pie Dept.

Advantages of the Xerox 820 Microcomputer over the IBM PC

by Gerald Grow

June, 1982

Author's Note: I kept this analysis I wrote in 1982 of the original IBM PC microcomputer to remind me that, no matter how well informed I am, no matter how reasoned my analysis, and no matter how articulate my argument, I can be terribly wrong. Sigh.

Such a document is a humbling reminder of the fallibility of expert predictions. Especially the predictions of those of us who are only modestly expert.

    In the Xerox microcomputer, you get a highly reliable “industry standard” microcomputer that will never lose its usefulness.  The CP/M operating system, 8-inch disc drives, Z-80 type microprocessor, full 64K memory, standard keyboard, excellent monitor, wide range of software, and many available printers and modems make the Xerox 820 microcomputer a superb choice for business applications.Xerox820

    Here is a summary of the features of the Xerox 820 microcomputer and how they can benefit you.

1.    Operating system. 

The operating system is CP/M 2.2, the industry standard for microcomputers.  There is more software available for the CP/M operating system than for any other system—including Apple, IBM, and TRS80.  According to recent reports, CP/M has been implemented on more than 450 brands of computer systems, with millions of users.

More and more manufacturers are turning to CP/M as their standard. When given the choice, experienced individual computer users frequently move to CP/M as their operating system.  According to the June 1982 BYTE, fully 20% of all Apple users have paid an extra $300 for a plug-in board that gives them CP/M capability.

CP/M is the most widely used and best-known operating system in existence.  It is the system most programmers use.

CP/M-based microcomputers have been adopted as the university standard at FSU.  This means that each year FSU will be graduating students experienced in the CP/M system, insuring a steady local supply of expertise.

There is an important library of CP/M software available for just the cost of copying.  These public domain programs contain many earlier, well-used utility programs, and even some newly developed games.  You can order these programs for the cost of the discs, or you can dial up certain sources and copy these programs onto your own discs over the phone.

There is a monthly magazine—MICROSYSTEMS—devoted to CP/M users.  It contains useful information ranging from helpful hints to highly technical analyses and construction projects.
2.    Disc drives. 

With the Xerox 820 microcomputer, you get industry standard 8” disc drives, with double-density option.

When considering a microcomputer, you should give careful consideration to the disc drives.  For any serious business or professional use, 8” disc drives are essential.  Ordinary 5” drives simply do not have the storage capacity to handle the larger, more powerful programs.

The standard drives for the Xerox 820 use “single-density, single-sided” (SDSS) discs, each of which holds about 241,000 units of data (conventionally referred to as 241 kilobytes, 241 Kb, or simply, 241K.)  By contrast, the single-sided, single-density 5” drives used on many microcomputers hold only about 100K.

This additional disc space can be crucial for word-processing, database management, mailing lists, financial programs, inventory, statistics, and other serious programs.

The additional disc space is extremely convenient, even if you are not using the larger programs, because it allows you to keep on-line more of the programs you frequently use—such as word-processing programs, programs to make backups, to move files around, to create indexes, and the most-used group of CP/M programs.

The Xerox 820 microcomputer is also available with double-density single-sided (DDSS) drives, for a modest price.  Each DDSS disc holds about 610K, almost three times the data of a SSSD disc, and more than 5 times the data of an Apple or IBM PC disc.  With the double-density adaptor, the Xerox will accept both single- and double-density discs.  It will even accept a single-density disc in one drive and a double-density disc in the other drive.

3.    Central processing unit. 

The Xerox 820 microcomputer uses time-tested and proven electronics.  It is an important synthesis of computer design, consisting of the best-tested, most widely available components in the microcomputer field.

The Xerox 820 is not a “new” machine.  It is a combination of rock-solid technologies.  More people use, understand, program over, and support the kind of electronics in the Xerox 820 than in any other microcomputer in the world.

In my analogy, the Xerox 820 is the “slant six” of the microcomputer field.  The slant six, you may recall, was that great Dodge engine that so many of us drove for well over 100,000 miles trouble-free—while many of the newer, more exotic engines were dying by the roadside.
The Z-80 family of microprocessor chips, combined with the CP/M operating system, is such an important combination that it will never become obsolete.   New computers will always come along that can do new things.  But the Xerox 820 will always do, and do well, what it was designed for.  It will never lose its usefulness.

“CP/M 2.2 is extremely important, and the Z-80 chip will live forever because of it.”—Dr. Portia Isaacson, Future Computing Inc., quoted in May 1982 Byte.

By comparison, the IBM Personal Computer uses several unproven technologies.  It has little software available for it.  The Apple, like the IBM, has small, limited-capacity discs and uses a microprocessor chip that has never been accepted widely outside of Apples.  

Although the new generation of 16-bit microcomputers brings some interesting new capacities—mainly because they can access more memory, and they can be combined more readily into multi-computer shared networks—don’t forget that this new technology will bring its new and undiscovered problems.  Some of these problems are beginning to surface in the letters columns of computing magazines.  Watch for them.

Every technology has to be debugged.  The greatest advantage of the Z-80, CP/m system used in the Xerox 820 is that it has already been debugged.  It is a known quantity.  Most of the problems have occurred, and they have been solved.

Remember when the first Volkswagen Rabbits came out?  Or the first passenger-car diesel engines?  Problems, problems.  Give the new computers a few years before you jump into them.  Let them find out what their problems are, not you.

Some computing magazines have given the Xerox 820 microcomputer lukewarm reviews.  Remember though, that these reviews are written by people mostly interested in new technologies, new advances, new experiments, new risks, and new problems.

Keep in mind that for the most part these reviewers are “computer hot-rodders.”  But notice what they use at home.  Most of those same reviewers, when they mention it, say that they themselves use the same Z-80, CP/M system found in the Xerox 820 microcomputer.
4.    Memory. 

Unlike the Apple, IBM, certain models of the TRS80, and other “add-on” computers, the Xerox 820 comes configured with the full 64K of RAM (random access memory).  There is no need to buy additional memory boards, as you must do with many small computers.

64K of memory is essential for most serious business software.  If you buy a machine with less memory, you will sooner or later encounter serious restrictions.

5.    Keyboard. 

The Xerox 820 has an excellent keyboard and screen.

The keyboard has a standard typewriter format with an added texturized surface that is especially useful in this sweaty climate.  The layout of the keyboard is solid, effective, standard, and immediately understandable.  Your employees will have no difficulty learning to use the keyboard—unlike the nonstandard keyboard on the Apple, or the very unusual keyboard on the IBM.

The keyboard is detached, which means that you can shift it around on the table so you can operate it comfortably from almost any position.  You do not have to sit bolt upright as if you were in a high school typing class.

Once again, Xerox has opted for the time-test, proven, and widely usable standard in its keyboard.  Nothing new.  Nothing lacking.  Nothing weird.  Just good, solid competent, thoughtful design which takes the best from what has been proven by long use.

6.    Monitor. 

The monitor on the Xerox 820 is clear, clean, pleasant on the eyes, and large enough.  To see how clear the Xerox is, compare it to an Apple color monitor that is displaying words of text.

7.    Software. 

Software is one of the Xerox 820’s strong suits.  Because of the CP/M operating system, the 820 has more software available for it than the Apple, IBM or TRS80.

This software is available from a wide variety of vendors, including all of the major program designers in the field.  Every serious program, or a version of it, will run on CP/M.  There are very few exceptions to this claim.

Software usable on the Xerox 820 is reviewed monthly in almost every major computer magazine.  The CP/M 2.2 operating system is so central to the microcomputers of our age, and there are so many of CP/M computers in operation that software will continue to be available for it.  Indeed, superb software has already been developed and is available for the vast majority of present business applications.

Remember that this software has been time-tested.  The problems have been discovered and corrected.  It is thoroughly debugged.

By comparison, watch the letters column in leading computer magazines for all the problems that are cropping up with new-design computers and the software to run them.

When you consider buying a microcomputer for your business, you have to ask whether you want something that is rock-solid in design, construction, and software, or whether you want to be a guinea pug in the first wave of experimenting with newly designed computers, their operating systems, and the hastily-assembled software to run them.

If you want to be on the wave of the future and have a passion for solving problems great and small; if you want to spend you spare time experimenting, discovering, and tinkering with untested technologies—then you may want one of the new 16-bit microcomputers, like the IBM, or an experimenter’s computer like the Apple.

But if you want something you can depend on, something that has already been developed and debugged, something that takes the best of the most solid and time-tested designs; if you want something that will do the job right, from the beginning—the Xerox 820 is you computer.

8.    Output devices. 

The Xerox 820 microcomputer will support a wide variety of printers.  If you need letter-quality output, the Xerox 820 is a good choice.  For inexpensive, high-speed dot-matrix print, consider an Okidata.  For a heavy-duty, very high speed, sophisticated dot-matrix printer, you want the Datasouth.

A modem is essential for connecting the Xerox 820 to other computers over the phone.  With a modem and the appropriate software, you can dial up large databases, giant host computers, link a group of micros into a local network, or join regional networks already in existence.

A modem can link you to electric phototypesetting equipment as well, for a direct transfer from you text files to typeset text.  This feature alone is worth the price of a modem to many users.

Modems come in a wide variety, but the chief distinguishing feature is speed.  300-baud modems are fairly cheap and transfer at about 30 characters per second.  1200-baud modems are more expensive, but could save you a fortune in phone bills if you make long distance data transfers.

Even though advances in microcomputers will continue to appear every few months—from now on! —the Xerox 820 microcomputer will always perform extremely well with the highly useful thoroughly tested programs already available.  You don’t have to wait for the future.  Indeed, if you are business, you can’t wait.  The Xerox 820 microcomputer allows you to choose the best and most reliable current microcomputer technology—and use it now—without becoming a guinea pig for the new, untried systems presently hitting the market.

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