Table of Contents
Weird Signal Processing – a VGA Hacking Workshop
as part of the AVX – Audio Video Experiment by Fundacja-X at
Kolonia Artystów in Gdansk
13. - 14. December 2019
Nam June Paik is known for manipulating a TV set with a magnet. One might think that after we abandoned monitor tubes the combination of TV and magnetism is gone as well. But similar techniques are still possible today by manipulating the monitor signal.
The fact that most signals used to connect devices via wires are based on electric current allows for easy hacking. For example one can manipulate the VGA video signal flow with coils and magnetic fields. The signal being similar to sound signals makes for an easy transfer to sound and vice versa. One can make a video signal hearable and display an audio signal on a monitor.
In the workshop we will process VGA signals. We learn the basic about the VGA standart and how to manipulate, mix and sonificate the signal, how to amplifier, invert and add fast video signals. Every participant will build a VGA breakout board that allows easy access to the signal.
Experimental VGA Processor
additional VGA Boards
VGA outputboard for the Raspberry Pi:
http://paperpcb.dernulleffekt.de/doku.php?id=raspberry_boards:raspberry_vga_board
VGA Breakout Board
http://paperpcb.dernulleffekt.de/doku.php?id=vga_synthesizer:vga_breakout_board
Fake a VGA device
Audio to VGA
VGA Signal Generator
VGAX Library for Arduino UNO
https://github.com/smaffer/vgax
HSYNC and VSYNC signals are squared pulses of +5V, and the RGB signals take values in a continuous analog voltage range from +0V (absolutely dark) to +0.7V (maximum brightness).
Connection
H-Sync – 68 Ohm – Pin 03
V-Sync – 68 Ohm – Pin 10
R – 470 Ohm – Pin 04
G – 470 Ohm – Pin 05
B – 470 Ohm – Pin 06
Inverting the Signal
I2C over VGA
Links
eater.net - VGA
lucidscience.com - pro VGA Video Generator
blogs.fsfe.org - VGA Signal Generation with the PIC32
javiervalcarce.eu - VGA Video Signal Format
gammon.com.au - Arduino Uno output to VGA monitor
github.com - VGAX Library for Arduino UNO
tinyvga.com - VGA Signal Timing
Homemade VGA Adapter