Arduino ESPVGAX Library 15/08/2018
This is a VGA Arduino library for ESP8266. It can display a 512x480 image with 1bit per pixel.
Like my VGAX Library, this Library require cheap components. You can generate a signal from an ESP8266 with less then 5$ :-)
ESPVGAX require a DSUB15 connector (aka VGA connector) and one 330Ohm resistor:
You can wire the VGA connector in some different modes that allow you to choose your preferred white color. For example you can choose to wire it up to use black and green colors, or black and purple.
You can find more informations about colors combinations here.
The Library also support two modes where colors can be increased from the standard 2 colors.
The first additional mode allow you to hook up an hardware PIN to one of the VGA pins (different from the primary color that you have selected in the first wiring). Thi hardware PIN is always ON when VGA signal pixeldata is generated, so you can change the background color from black to another color. This change is permanent and you cannot turn ON/OFF this background color variation.
The idea behind the second additional mode is this: ESP8266 HSPI can send data to VGA as a serial stream of bits, so it can only turn one VGA PIN ON/OFF at a time. But VGA timing has gaps between lines that can allow more code to be executed, before and after sending the stream of bits. So, before sending the data, the Library can turn ON/OFF some other bits and change the color combination used in each horizontal line (480 lines).
The VGA signals can become unstable if your code uses Wifi, Serial, and other Arduino classes. You can find more informations here.