Hi Russ,

As a matter of fact we have two boys, we homeschool them both, and I was just minutes ago in the living room explaining to my 12 year old how to multiply through by tens until he's dividing a whole number into something (showing him that the ratio remains constant).

Yes. There is value to teaching kids long division, and how to find a square root, and the Dewey Decimal System and many other things that they may never have a practical use for. It's called education.

Consider the topic of another thread that's evolving right now. Someone asked (and hasn't returned yet that I can see) about extending the ports of an 8051. Someone else invariably brought up the 8255 which of course seeded the avalanche of pro/con arguments.

Now perhaps the most notorius of our numbers to hate the 8255 is Erik Malund. And I don't even come close to having the electronics experience or expertise to challenge anything Erik might say about µ-controllers or the related circuitry. And even if I did, I wouldn't challenge anything he says about this subject because I largely agree with him.

Nonetheless, I do take exception to his position in one regard, and it applies to precisely the question you raise.

Indeed, there are too many better choices to use an 8255 in a real product today. However, when teaching a student about µ-controllers there is value in making them learn how the 8255 works. It's foundational.

Think about compiling code. I would never suggest that Erik develop one of his projects by writing his code directly in binary, or by manually assembling an *.asm file and then manually producing the Intel Hex file. But if I were teaching a student learning this material for the first time I would do just that (with a very simple program of course).

Just because we have opamps doesn't mean we shouldn't teach bipolar transistor amplifiers. And if anyone graduates from an electronics school but can't do the load line analysis of a transistor amplifier circuit, then their electronics education is wanting at best.

So yes. There is value in learning long division. It's foundational. It's education.

And that's my two cents worth,

Joe