A little toy: Lissajous figure demo

[NoCforMe]

Here's a li'l something I cooked up more than a decade ago, at the point where I first learned to use the FPU. (Actually I didn't learn to use the FPU directly, but used Raymond's FPU library instead. Much slower, but in this case it doesn't matter at all.)

Source and all attached.

[HSE]

Look like critical file "FTDengine" dropped. 

[NoCforMe]

Sorry, I had to re-upload the zip file--twice--because I forgot to include stuff. Pain in the butt keeping track of all the little files needed for a project you did >10 yrs. ago. Latest one should be complete ...

[Biterider]

Hi NoCforMe
Cool stuff, it reminds me of when I was a student (many years ago).

used Raymond's FPU library

Raymond's FPU library is a great work. It helped me understand the internal working of the FPU much better than the old textbook I started assembly programming many years ago.

Biterider

[NoCforMe]

Hi NoCforMe
Cool stuff, it reminds me of when I was a student (many years ago).

So did you actually play with an oscilloscope back then? Unfortunately I never did that; would be tres cool to get a 'scope and a couple signal generators and look at the kewl patterns in the analog realm ...

(I have a scope--a friend gave me his old Tektronix 475. Now I just need to rig up a couple oscillators ...)

[Biterider]

Hi NoCforMe

So did you actually play with an oscilloscope back then?

Yes, I was very lucky in that respect. I had a physics teacher who was very talented and could really inspire his students with very little material.

Biterider

[mineiro]

I already played with a teknonix in a polytechnic school, 2 channels. School only had nerds, I was the ignorant one there. I forgot much of what I learned.
The project made was a simple bandpass, high or low pass. At the time I was more into square waves, digital electronics.
These days sometimes I play with ltspice, a great program.

Your program works fine in linux under wine.

[NoCforMe]

At the time I was more into square waves, digital electronics.

You do realize, of course, that square waves are also squarely in the analog domain. (Pun intended)

Like how if you take a sine wave and keep adding odd-order harmonics to it you end up with ... a square wave. (I have a demo program for that, too. May post it later.)

BTW, it turns out that most "digital" electronics are actually analog; they just are set to generate or detect voltages that conform to "digital" specifications, more or less. In electronics, nothing is really digital.

These days sometimes I play with ltspice, a great program.

Yes, I've played around with Ltspice a lot too. Actually used it to design actual (small) circuits that actually worked. (Not a very good design technique I'm told, BTW, but very helpful for a dummy like me.)

[NoCforMe]

Here's another educational toy I made that shows what happens when you add odd-order harmonics to a square wave. (I was really surprised when I first discovered this phenomenon.)

Hopefully I got all the bits and pieces in the .zip this time ...

[mineiro]

Oh yes, like cut the amplitude of a wave using some bandpass filter, I suppose it is rlc (resistance, capacitor and inductor), I really forgot, it starts to charge from a certain projected voltage to the peak voltage and after that it discharges in a give time, giving the impression that the voltage remains constant (a straight line) on the oscilloscope. I suppose so.

What was a failure in analog electronics turned into the creation of digital electronics, transistor (diodes) saturation.
I studied this 25 years ago as a teenager.

-----
I will test your other program now. 

----edited-----
Yes, exactly this, very nice. Congratulations.

[daydreamer]

So did you actually play with an oscilloscope back then? Unfortunately I never did that; would be tres cool to get a 'scope and a couple signal generators and look at the kewl patterns in the analog realm ...

(I have a scope--a friend gave me his old Tektronix 475. Now I just need to rig up a couple oscillators ...)

Get DA converters from printer port you could output fpu to your tektronix,unless you code a driver,you need to run it in dos
X/y mode you can code vector graphics