PART 2. A Bit About the PC
First, it is important to tell you what we mean by the term “PC”. IBM started 5 years ago with their first model, the IBM PC, which meant “Personal Computer”. There was an early rush by about a dozen companies to make “PC Compatible” computers. That is, computers which were functionally the same. The intention was to make alternative machines at a lower price which would run the same software as the IBM PC. For the most part, these compatibles were very different from the IBM computer electronically. From the software standpoint, different brands offered differing degrees of compatibility.
In just the last year, manufacturers have been able to reproduce both the electrical AND functional aspects of the IBM exactly. It is virtually impossible to tell the difference. We use the term “PC” to describe all of these EXACT reproductions. Other terms which have equal meaning are “Clone” and “PC Compatible”. IBM came out with an improved version of the PC which it called the IBM PC/XT. Most clones on the market offer full compatibility with both IBM models. There are, however two other IBM models which are NOT to be confused with the PC: the IBM PC Jr. and the IBM AT. These machines will run much of the same software as the PC, but electronically, they are quite different.
To one who has used a Timex computer, the PC is a very interesting machine because in some respects, it is the exact opposite of a Timex, yet at the same time, it is startlingly similar. Let me explain.
The Opposites
My overall impression of Timex computers is that it offers the finest Basic language, the most efficient use of memory and the most sensible operating system of any other computer. However, it fails horribly in a crucial aspect that practically ruins its usefulness. Timex hardware is awful. On the TS1000, overheating and rampack wobbles, the poor quality video, the membrane keyboard, and unreliable, slow cassette loading are enough to try the patience of Job. Hobbyists and experimenters have made great attempts to correct these shortcomings, but in most cases, it involves a great deal of tinkering to get everything working right, and even more tinkering to keep it that way. The TS2068 fixed many problems of the 1000 computer, but the “wavy” video, still slow tape loading, and bad keyboard leave many problems only slightly corrected.
The PC is just the opposite in this respect. It gives you very nice hardware and software that stinks. You get beautiful video: clear, sharp, rock steady, able to be read from opposite sides of a room. You get just a ton of memory. Most clones come with 640K built-in. The power supply gives no crashing problems, and disk drives are fast, reliable, and store gobs of data. Anyone who has fussed and fumed over a Timex will think they’ve died and gone to heaven when they start working with the PC hardware.
Looking at the operating system and its associated software, a Timex enthusiast would see a real mess however. It appears to be a hodge-podge of routines which were written by a hundred different people. Everything was pieced and patched together, but nobody ever really cleaned it up. As a result, it is very wasteful of memory space, slow considering the speed of the microprocessor, and quite cumbersome. The Basic programming language consumes over 60K. Syntax checking is completely lacking, programs can be a maximum of 64K in length (even if you have 10 times more memory in the computer!), and a faulty program line can crash the PC like a bad USR call does on the Timex.
I find it to be particularly ironic that we ZX/TS fans have put up with continual harassment from PC users who told us we had nothing more than a toy when in actuality, it was they who were forced to work with such inferior software. They didn’t know what they were missing, and we didn’t know how good we had it!
The Similarities
After all my complaining, you might wonder why we even suggest bothering with the PC. Actually there are a lot of reasons. They revolve around the similarities I see between the PC and the Timex.
When you strip away the bad operating system you are left with a wonderful machine. It is extremely simple the way it works. There is nothing technologically advanced about it. There are no mysterious chips, esoteric functions or fancy hardware. At its gut level, the PC is nothing more than a very souped up ZX81. A machine code programmer can take complete control of the machine and make it do whatever you want. This is in contrast to the more technologically advanced computers like the TS2068, the QL, the Atari, Amiga, and MacIntosh where sophisticated hardware can often make a programmer’s life miserable.
Also of interest to the machine code programmer, is the 8088 microprocessor in the PC. This chip comes from the same roots as the Z80 which means that the methods and philosophies used with the Z80 can also be applied to the 8088. Many MC instructions are identical or are only semantically different. For example, the Z80 term, “LD A,00” becomes “MOV AL,00” in the PC. It is very easy to make the transition.
For the Non-machine code programmer, who’s probably thinking “big deal” at this point, these similarities have important consequences for you too. Because the PC is so easy to program in machine code, many of the shortcomings found in the operating system have been circumvented by applications software or additional system software. This stuff is widely available in the public domain libraries I mentioned in the last section on the PC. Probably half of all software in these libraries could be categorized as “Utility” software: Toolkits, patches, and enhancements which fill the holes left by the operating system.
A MODULAR Computer
Unlike Timex computers which come, more or less as a complete unit, the PC is a “modular” machine. By this, I mean that different components are assembled into one complete system. This is a very nice feature because you can pick and choose your components so the computer ends up exactly the way you want it. It also means that you can buy a PC practically as a kit and assemble it yourself just by plugging the right boards together. Unfortunately for many who are used to buying a unit they can just plug in and go with (like a Timex computer), this modularity can be a mixed blessing if you don’t know which components you need to get in order to have a fully functioning PC. Even for the experienced hacker, it seems that no matter how many components you add, there’s always one more that you haven’t got. But even Timex machines are like that, it seems.
To avoid disappointment, it is very important to know what parts you need to get BEFORE you place an order. Many vendors sell complete packages often at a significant price savings over buying individual parts yourself. But even with these packages, there is a wide variety. You need to know what is included and what is not. Below I have listed the components necessary to have a functional PC system.
1. Motherboard:
This is the main circuit with the ram and micro processor on it. It also includes a keyboard connection, and a number of expansion slots (usually 8). Some boards come with just one clock speed like the PC. Others called TURBO boards give you two or more speeds. TURBO boards generally boost computer speed about 50%. Motherboards are often sold without ram chips installed. If the ads say “0K RAM”, be prepared to spend $20 more for ram chips. 640K is the most memory the PC is able to handle without additional bank switching hardware. Be wary of motherboards which do not at least provide sockets for this much ram. If they don’t, it means that you’ll need to buy a ram expansion card.
2. Keyboard:
Detached keyboards have a coiled cable which stretches to the back of the PC and plugs into a connector on the motherboard. Be sure the cable is nice and long. Several styles of keys are available. All are a dramatic improvement over the Timex, but some PC keyboards, never the less, are better than others. I prefer one with large ENTER and SHIFT keys. These keys on some boards are no larger than the regular alpha keys.
3. Power Supply:
Unlike the Timex power supply which is measured in Milliamps, the PC supply is measured in WATTS. It includes a fan and ON/OFF switch. You should probably look for the highest wattage you can afford. As you add peripherals, power consumption goes up. If you plan ahead, you won’t need to buy a larger supply later. A good size to start with is something between 100 and 200 watts.
4. Video Adapter:
There is a large and confusing variety of video adapters on the market. You must be careful to choose the one to suit your needs. Some of the types are listed below:
monochrome video adapter: this is the cheapest and requires the use of a TTL level monitor–NOT a TV set or a composite video monitor. This adapter will only print text and block graphics. You cannot plot individual pixels. But what you do get is absolutely beautiful text displays at a reasonable cost.
monochrome graphics adapter: Same as above. Only you can plot pixels on the screen if you can figure out how. The Basic language will not let you access pixel graphics with this adapter. There is very little information out which tells how to work the graphics mode of the MGA. However it will give extremely high resolution (720 X 340), and in text mode, the picture is stunning. This is my personal favorite for word processing. It has two 32K display buffers which eliminate an annoying flicker (you heard it right–screen flicker) which occurs with the other types of display adapters. This board also has a built in parallel printer interface. The first adapter of this type was called the “Hercules Graphics Adapter” which set something of a standard used by virtually all other monochrome graphics boards.
color graphics adapter: This board (the CGA) is perhaps the most frequently used video card. It prints text and also lets you use Basic to access individual screen pixels (640 X 200). Several modes of operation with up to 16 colors are possible. This adapter works with either an RGB or a composite video monitor.
5. Disk Controller:
Some controller cards allow you to connect 4 different disk drives. Others like the one I use are called “Multi-IO Cards” which connect just 2 drives, but also provide you with another printer port, 2 RS232 serial ports, and a battery backed clock calendar. Choose the card that fits your needs.
6. Disk Drives:
At least one disk drive is necessary, but making do with just one can be a bother. You are much better off getting two disk drives. When shopping for drives, don’t go for the bargain basement specials unless you are sure they will work reliably. Remember, they probably are on sale for a reason. It may be that they are not up to snuff. If you buy a package deal from a vendor, be sure you know how many disk drives come with the base unit. Often, the second drive costs extra.
7. Case:
The motherboard, power supply, disk drives, and assorted expansion cards are all made to fit inside a big steel enclosure. Cases come in two flavors: the flip-top and the slide-in. I understand that the flip-tops often have trouble passing FCC noise regulations, but they offer convenience in getting to the various components inside.
8. DOS
All the other components were hardware items. DOS (or MSDOS–the Disk Operating System) is the one software module which is absolutely essential. Without it, your system is worthless. The operating system comes on a disk. When you turn the computer ON, the DOS is loaded into memory and runs. This is the software which reads the disk drives, keyboard, etc. Frequently, vendors who sell package deals do not include DOS with the computer, however many do. Don’t expect it unless the dealer specifically states that DOS is included. You may need to buy MSDOS as a separate item.
The DOS disk contains many useful utility programs and the BASIC programming language. BASIC is an interpreter like Timex Basic. There are many different versions of BASIC. Many are quite different in the way they work, but all are functionally about the same.
Finding a Supplier
The list above shows all the parts necessary to put together a complete working system. As with buying a car, there are, of course, many “extras” you can add if your needs and pocketbook allow it. Finding a reliable dealer to supply all these components is not always the easiest proposition, however.
A brief look through a magazine like “The Computer Shopper” will reveal over a hundred different places to look, but how do you know which dealers are honest and reputable? I recommend three methods for finding a good supplier:
1. Rely on product reviews or advice from people you know who have purchased a PC.
2. Buy a name brand product like an Epson or Tandy.
3. Go to a dealer you have dealt with before. Many Timex dealers are now branching out and offering PC compatibles. E. Arthur Brown Company, Knighted Computers, TEJ Computer Products, and HAL-Tronics are some that we know of.
Prices vary dramatically from dealer to dealer. We have seen them range from $500 to $1000 depending on what you get.
Continuing the PC Saga
There is still a LOT more to be said about the PC. You can expect to see more in future issues of SWN. While you’re waiting for us to get the next issue out, let us refer you to a few other sources of PC information which we have found useful.
Soft Sector Magazine, Dept. SWN, P.O. Box 385, Prospect, KY 40059
(the SYNC Magazine of the PC world)
1001 News, Rt. 1, Box 112, McHenry, MS 39561
(A nice beginners publication for the Tandy 1000 models)
PC Resource, 80 Elm St., Peterborough, NH 03458
(Full of Ads and a lot of good nuts and bolts info)
MicroCornucopia, P.O. Box 223, Bend, OR 97709
(The SWN of the PC World… At least for now!)
E. Arthur Brown Co., 3404 Pawnee Dr., Alexandria, MN 56308
(sells Tandy computers at discount)
Hal-Tronix, P.O. Box 1101, Southgate, MI 48195
(sells generic PC clones)
Thomas B. Woods, Box 64, Jefferson, NH 03583
(that’s me! sells PC Findex aka Pro/File