C64 and Analog Computers

[trekiej]

Has anyone here hooked a C64 to D/A or A/D converters?
Also, does anyone here have any analog computing experience?

[RobertB]

Has anyone here hooked a C64 to D/A or A/D converters?

Well, there is the Sound Ultimate Xpander 6400 (SUX 6400) at

http://retro-link.blogspot.com/2011/07/sound-ultimate-expander-6400-audio.html

for digitizing audio.  And there was the C128 Video DAC (RGB digital to VGA), the thread beginning at

http://www.commodore128.org/index.php?topic=3877.0

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug

[trekiej]

Thanks.
I was wondering if it is possible to make an analog compressor and de-compressor.

[bloodline]

It would be very easy to hook up an Arduino to a C64 via the serial port... And use that as an A/D device

[trekiej]

Serial computers and Analog computers are for some reason an interest to me.
I wonder if an Analog comp. could match a C64 if it had good enough Delay-Line memories, etc.

[Zac67]

RU sure you're meaning analog computers?

[lsmart]

RU sure you're meaning analog computers?

My thought exactly. I don`t even get what he is talking about. Maybe he is referring to the SID synthesizer chip but that's just a wild guess. While the chip can generate "analog" sounds you can do sampling as well, because the oscillators are digitally controlled. The C64 can do D/A by itself and via the joystick port (or better the datasette) also A/D. Unfortunately the hardware isn`t very good at this.

And if he is talking about synthesizer chips, he might be interested in Adlib PC soundcards as well, which are the primary thing that comes to mind, when talking about FM-synthesis, right?

[trekiej]

yes, analog.
I sounds like a hybrid concept is a good way to start.
The Delay-Line memory is for serial computers, not for sure if it is for analog though.
I believe an op-amp for a sample and hold maybe right.

[RobertB]

yes, analog.

The only analog computers I've seen are the electron tube-type computers I've seen at the Vintage Computer Festivals and at the Computer History Museum.

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug

[trekiej]

I hear Op-Amps are the ones to look to for design.
Edmond toys had 3 pots. and a galvanometer for finding the answer.

[trekiej]

http://www.youtube.com/watch?v=TJFXEny-Pt0
I thought this was cool.

[Ami_GFX]

The most common analog computers use op amp circuitry: Adders, subtracters, multipliers, integrators, differentiators, logarythmic and expontial amplifiers among others. They are very similar to analog modular synthesizers in their ciruitry. Equations are programed by patching modules together. They are more like real world mathematical modeling systems than computers in the digital sense.

I've gotten to play with a few modular synthsizers in my time and I've seen pictures of analog computers that looked like they would be interesting audio processors among other things they could do.

Here's a couple of examples of analog computers:

http://retrothing.typepad.com/photos/uncategorized/2008/10/01/comdyna3.jpg

http://archive.computerhistory.org/resources/physical-object/general_precision/X42-79.1.lg.jpg

And here are pictures of Serge and Moog modular synthesizers for comparison:

http://www.serge-fans.com/images/serge3panel.jpg

http://www.synthtopia.com/images/Arturia_moog_v2.jpg

[Speelgoedmannetje]

A while ago, I asked an engineer who worked with computers since the 60's about analog computers, he told me these were extremely fast but also very very unreliable.

[trekiej]

I found drum sequencers to be a cool item to have.
I wonder if a sample/hold circuit would be analgous to a digital register.