LOGO
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Sep 11, 2004
Subject: Re: [cosmacelf] 1802 Logo 

Lisp is one of those fascinating languages that I've always meant
to get around to learning (but never did). It is the basis for so many
truly unique and powerful programs.

One of them is Logo. Logo came out of Seymour Papert's work on a
language specifically tailored for children to learn about computing.
Logo began with a "turtle" robot (a little tabletop robot shaped like a
turtle). You learned the commands to tell it to go forward, back,
turnleft, turnright, and raise/lower a pen so it could draw a trail of
its path on a sheet of paper.

My son is now 9 years old, and ready to learn about programming. Logo
seems like a wonderful introduction to programming and logical thinking.
I even have an 1802-based robot!

So... my pet idea is to bring up Logo on my robot, and turn my son loose
with it. Moreover, I have ten of the MSI/88 1802 computers that are just
begging to be turned into an army of turtle robots, to take to school!

Any one else think this would be an interesting idea?
--

Sep 11, 2004  5:59 am
Subject: Re: [cosmacelf] 1802 Logo 

J.C. Wren wrote:
> Teach a man's programming language:  Forth!  The one *true*
> programming language. Followed by assembly, then C. :)

(This reminds me of that old joke sheet that says, "Real programmers
don't program in..." and then it proceeds to denigrate every known
computer language one by one :-)

Seriously, I've been trying to teach [my 9-year-old son] Tiny BASIC. It is actually
pretty well suited for kids. It's an interpreter, there are very few
keywords, and what each one does is very simple.

It is hard for adults to realize is that kids think very differently
from adults. For one thing, their logical abilities are almost
non-existent. For another, they solve problems by trial-and-error. They
also cannot solve problems that involve more than a very few steps
except by rote memorization.

So, languages like Forth or C are out. They are just plain too complex
for young children. Their very power and richness become a curse.

The keyboard and screen are a curse for almost all computer languages.
They require that you be able to read and type well. Kids also have
problems with the extremely rigid syntax and grammer of computer
languages.

Logo was designed to address these problems. It can be used even by kids
that can't read and don't even know the alphabet. In its most basic
form, you have keys for:

	 numbers
	 forward
	 backward
	 left
	 right
	 to
	 enter

Each of these is a single key; for instance, the four arrow keys are
used for forward, backward, left and right. The user types a sequence of
keys, then Enter to say "do it." For example:

forward enter (robot moves 1" forward)
forward 5 enter (robot moves 5" forward)
right 90 enter (robot turns clockwise 90 degrees)
forward 12 right 120 forward 12 right 120 forward 12 enter
	 (robot moves in a 12" triangle)

"To" takes whatever key you hit next, and redefines it to do whatever
the sequence of keys that follows directs (i.e. it creates a
subroutine).

to x forward 12 right 120 forward 12 right 120 forward 12 enter

After this,

x enter (robot moves in a 12" triangle)

The idea is that kids learn by trial and error what the keys do. They
experiment with numbers to figure out what number to type to get the
robot to move a given distance, or turn a particular amount.

As the child masters these, more commands are added. "Penup" and
"pendown" allow the turtle to draw things on paper. "Repeat" allows
repetitive actions. + - * / add math (forward 2 + 2 goes forward 4"). A
complete, powerful, structured programming language gradually emerges.

So, my thought is to put a couple stepper motors and wheels on the
MSI/88, program it with an 1802-based Logo, and let the kids have at it!
Draw their name, teach it to run a maze, or sumo-wrestle. And in the
process, begin learning the wonderful world of math, logic and
programming.