Inside stuff -- flowcharts and experiments

Want to know more about what goes on inside your computer? It isn't as complicated as you might think.

If you want to know what a computer program really looks like, then I will introduce you to the BASIC programming language and show you how you can actually write a short program of your own.

• Software -- run the programs first
• Flowcharts -- see what they do and how they work
• Getting started with QBASIC -- write your first program
• Experiments -- your computer is a personal learning lab
• Try it -- two experiments with time and numbers

Software

There are six programs in Ainsworth Computer Seminar 1 that you can run to get a quick idea of some of the things your computer can do. If you haven't run these programs yet, I suggest that you begin with them, and then return to this section for more information on how software is written.

Link to the six programs. Try these now, if you haven't done so already.

The first step in writing any program is to get a clear idea of what you want the computer to do. You don't need a complete description of every step, but you will need a basic concept to begin with. I usually organize my ideas with a simple flowchart. As the program develops, I may use many different diagrams to show how the computer instructions combine to create a finished program.

Flowcharts

I like flowcharts and I use them a lot. In creating the Ainsworth Keyboard Trainer 4 software, I drew at least a hundred diagrams like this one to help me visualize the program and the design as it progressed.

The flowchart that follows each of the seminar programs is not much more complex than the example on the right. If you follow these diagrams they will quickly show you the important points in each of the examples. These flowcharts are really the first step to seeing what the computer is doing when each of these programs runs.

This computer road map is ideal -- if you tend to think of things visually. Here's how to find out and what to do next:

• If this diagram makes sense, then flowcharts are going to help you a lot in understanding my work, analyzing other software, and even creating your own.

• If this diagram sort of makes sense, then check out Flowcharts -- a computer road map for details on how both the program and the flowchart were created. You can even run the real Guess a Number program on your computer and see what it does, if you want.

• If flowcharts are still a mystery even with my wonderful diagrams and artwork, don't despair. Not everybody thinks about ideas and processes in a visual way, even though we all say "I see" when we mean, "I understand." If the flowcharts don't help you see or understand, then just skip them.

Getting started with QBASIC

You don't have to be a nerd-in-training to learn about programming or to find out a lot about how computers and software work. At least not with my short course that will have you writing an actual program in mere minutes. In fact, all you really need is curiosity, a computer, and the seminar materials that are included on the CD-ROM or that magically appear on your desktop when you download and unzip the Ainsworth Computer Seminar 1 from the Internet.

If you already like to write songs, jokes, stories, or poems, then writing software might just be an interesting way for you to express your creativity. Ditto if you like to invent games, think up puzzles, draw pictures, compose music, or make up plays. A poem written on a computer isn't any better than a poem written on the back of an envelope, but computers are becoming increasingly important to creative people in many fields.

See for yourself. If you choose to try the Really really basic BASIC section of this seminar, one of two things is likely to happen. It's possible that you will discover that you wish to use computers as an integral part of whatever it is that you do in life. It is also possible that you will simply gain a better understanding of computer software, and be better equipped to select and use programs that others create. Either way, you win. And so do I.

Your guided tour begins with Really really basic BASIC

Experiments

Everything I know about programming I learned by experimenting with computers. I ignored the programming courses and books that existed when I first became interested in computers because they were all geared towards business machines, accounting, and other industrial applications. This is boring beyond belief if you want to use computers for something besides crunching numbers and printing bills or payroll checks.

Things are different now, and there are lots of good sources for learning how to write creative software. But your best source will always be your own curiosity, and experimentation will always be your best teacher. When you experiment with software there are a couple of things to keep in mind:

If you want to see what a computer instruction or a section of computer code will do, test it. Just run QBASIC, type your instruction, and then run it to find out what it does. NOTHING is more positive than this. It doesn't matter what the book says or the manual says. What happens is the event.

Before you change anything in a program, whether it is yours or someone else's, make a copy and change that. It is wonderful to be able to go back to the original without any penalty. This makes you fearless and gives you license to try anything you like, just to see what will happen. I often make a series of copies as I am working on a program. This way, if I get into trouble I can just go back to the previous copy and see what went wrong.

If you are trying out an idea, start small. Get the essential parts of a program working first, and then add the bells and whistles. Don't waste time fussing with the details like the artwork or the appearance if the basic idea doesn't work.

Try it!

Exploring random numbers with your computer -- There are many ways you can use random numbers generated as you create everything from art to music. A special function in the toolkit makes using random numbers easy.

Exploring time with your computer -- Timing is very important if you are creating games and interactive programs. This set of experiments shows you some of the ways you can use the computer's internal timer to measure, evaluate, and control aspects of your programs.