Flowchart your way to success

      7 Comments on Flowchart your way to success

Does anyone still use flowcharts for programming?

What with today’s complex development frameworks it seems unlikely that anyone’s stopping to draw diagrams on paper. But maybe if they did we’d have fewer security vulnerabilities – just sayin’.

My addiction to computers, in the early 1980s, was driven in part by ‘30 Hour Basic‘, an introduction not just to the language but also to programming concepts. (The image on the right shows the BBC Micro-oriented edition I have now, not the original one based roughly on Microsoft Basic that I had in the 1980s.) I read it before my first computer even arrived. And one of the ideas that struck a chord was the idea of using flowcharts to map the logical flow of a program or algorithm.

This book is full of flowcharts. And while I’ve read many programming books since, none has done a better job of explained the logic of a program.

While waiting impatiently for my ZX Spectrum, I drew a lot of flowcharts. I even bought myself a flowchart template – a stencil, if you will – to make the diagrams neater.

When I finally got to type in my programs, and they crashed, the flowcharts were actually useful in reminding me how the programs were supposed to work. That eased the pain of debugging a little.

Of course, once I had a computer in my grubby little hands and could enter actual code and watch it run immediately I never drew a flowchart again. But there’s still something about them I like.

I kept the template for years. But, as with so many things, it was eventually lost due to the ravages of time and my sloppy housekeeping.

Then, recently, I saw a post on the Computer History community on Google+ (yes, it’s still going) showing pictures of ‘tools of the trade’ from when programmers really were programmers. One of them was a flowchart template.

Nostalgia, eBay and PayPal form a dangerous combination. Long story short, I have a flowchart template again.

This is nothing like the one I used to have. But it is a pleasant piece of vintage computing history.

It was made by Burroughs, which became Unisys after merging with Sperry Univac in 1986. It dates from 1973, which explains some of the options. There are the standard flowchart shapes – Input/Output, Process, Preparation, Decision etc. Those are still relevant. Others might not be of great benefit to modern-day programmers. The shape on the top right represents disk storage, which is okay, and also drum storage, which might puzzle your average Android app dev. There are shapes, too, for Punched Card, Punched Tape and Card Deck.

The plastic is transparent and there are scales along the bottom and left-hand side for reading the rows and columns of punched cards. Along the top is a ruler in inches – none of that perverse Continental metric nonsense. And on the right hand edge are rulers marked in sixths and eighths of an inch. Not sure what those are for – punched tape maybe?

For those who like standards, the template apparently conforms to ANSI Standard X3.5-1970, ‘American National Standard Flowchart Symbols and Their Usage in Information Processing’.

So, maybe it’s time for me to start flowcharting my programs again. Now, where did I put that drum?

 

7 thoughts on “Flowchart your way to success

  1. Richard P

    I do! As I write technical specifications for applications that get developed by large teams, I find it easier to explain in a picture.

    The technology has changed, but now I just use Graphviz DOT. Simple syntax and I don’t need to spend time on doing pretty layouts.

    Reply
  2. William Lindley

    Printouts were almost always 6 or 8 lines per inch, thus the vertical rulers. The horizontal ruler is in tenths of an inch, a very uncommon thing (ordinary rulers are in 1/16 inch) but particularly useful because printers, like typewriters, used 10 characters per inch. With both the horizontal and vertical rulers, you could easily find the row and column of anything on a printed page.

    Reply
  3. Andy R

    I still have my WH Smith branded flowchart templates somewhere. Never used them outside technical college though.

    Reply
  4. Lawrence

    Flow charts are still occasionally useful, if nothing else then to force you to think about a problem before going straight to code. Or for wanting to explain a design to others etc. Programs (and programming) are more then code.

    And yeah tools like Graphwiz is the way to make them, as much as fun as the little templates were.

    Reply
    1. Machina Post author

      Until I wrote this post I wasn’t even aware of Graphwiz. Looks like a useful tool. I like that it’s cross-platform, too.

      Reply

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