Although the optical-acoustic result is not too spectacular, the way it is generated, but already: Matthias Kramm, studied computer scientist residing in California, survived the floppy drive 1541 by Commodore to produce highly tones and images.
Demo video of the author Matthias Kramm
For sound output, he’s naturally used the Stepper engine of the drive – C64 friends will remember the Larm, which produced the qualifying slow floppy station, still well. However, the image output on a classic FBS monitor requires a small modification: a simple 100 ohm resistor mixes sync pulses and image content together.
Switching diagram of the modification: Only one resistance is also necessary.
The built-in processor, a 6502, generates the video signal over bit-banging the port bits lying on the connecting cable itself. Dafur Kramm had to reach pretty deep into the trick box, because the CPU, which was clocked around 1 MHz, processes only about 400.000 commands per second; The resolution of the resulting (black and white) image is therefore quite low. Nevertheless: Hat from for this idea!