Re: I love my Apple II

[Cyrus Roton <croton@ridgecrest.ca.us>]

Not everyone knows how versatile the Apple II really is, and the limits 
of it's usefullness have not yet been found.

I use my IIe to plot the frequency responses of linear circuits (gain and 
phase angle as function of frequency). The program can be used for 
practical design applications as well as for education. Also, I can input 
audio signals to an external digitizer and dump the data into the IIe for 
Fourier analysis (via a simple interface I built). Once I know the 
harmonic structure of an "input" waveform, and have the circuit gain as 
a function of frequency, the machine can give me the harmonic structure 
of the output of a filter circuit. That proved usefull in designing 
filters for an electronic organ I designed and built.

In designing the "control panel" for the organ, I decided that a PROM 
could replace a lot of of logic circuitry. So, I quickly wrote a little 
program which simulated the switches on the panel, used the switches as 
address data to the simulated PROM (in memory), and took the output data 
from the simulated PROM to drive simulated control functions. After the 
PROM data was perfected, and all the simulated functions appeared to work 
correctly, on screen, I used the data to burn an EPROM (using the 
Apple II with a PROM burner card). When the organ was completed, those 
circuits worked correctly, thanks to simulation on the Apple II.

Currently, I am assisting a student in constructing a mock-up weather 
station for a science fair. The temperature is measured by a thermister 
connected to one of the paddle ports of the Apple II. Wind speed will be 
measured by connecting one of the game switch ports to an optical 
isolator which has its light path "chopped" by a rotating disk. The 
frequeny of the chopped signal will indicate the wind speed and will be 
measured by a "frequency counter" program (which was very easy to write 
in 6502 assembly).  The wind direction will be detected by having an 
8-bit decoder on the weather vane. The data from the decoder will be 
passed to the Apple II via the same interface I used with the digitizer. 
All that information will be displayed on the screen in graphics.

These things are easy to do on the Apple, with very little cash 
expenditure. Those of us who still love the old Apple II can find 
inovative ideas for practical uses, regardless of the negative comments 
of people like "Endless Mouth" who seldom have any constructive comments.

All right, I will admit that most of the time I use a Macintosh, because 
there is much I do on it that would be difficult or impossible on the A2. 
But the kind of things I mentioned above, I can not readily nor easily do on 
the Mac (nor on a PC). AT least, not without spending more money and 
spending a great lot of time learning to program those machines.

Why not use simple solutions to simple problems. One does not use a Rolls 
to plow a field.

Cyrus Roton   croton@ridgecrest.ca.us
Ridgecrest Apple User Group