What is the full form of VGA

VGA: Video Graphics Array

VGA stands for Video Graphics Array. It is a display hardware developed by IBM in 1987. It was first introduced with IBM PS/2 line of computers. It provides a resolution of 640x480 pixels and a refresh rate of 60 Hz.

VGA is referred as an array instead of an adopter because it was implemented from the start as a single chip (ASIC). It uses analog signals rather than digital signals.

Technical Specifications

The original VGA has the following specification:

• 256 kB Video RAM
• 16-color and 256-color paletted display modes.
• 262,144-color global palette (6 bits, and therefore 64 possible levels, for each of the red, green, and blue channels via the RAMDAC)
• Selectable 25.175 MHz or 28.322 MHz master pixel clock
• Usual line rate fixed at 31.469 kHz
• Maximum of 800 horizontal pixels
• Maximum of 600 lines
• Refresh rates at up to 70 Hz
• Vertical blank interrupt
• Planar mode: up to 16 colors (4-bit planes)
• Packed-pixel mode: 256 colors (Mode 13h)
• Hardware smooth scrolling support
• No hardware sprites,
• No Blitter, but supports very fast data transfers via "VGA latch" registers.
• Barrel shifter
• Split screen support
• 0.7 V peak-to-peak
• 75 ohm double-terminated impedance (18.7 mA, 13 mW)

Shape and Size

A VGA connector is shaped like a trapezoid and it has 15 pins. If you have a old monitor designed for the older standards may not be able to work with Video Graphics Array standards.

Compatibility

The older VGAs provide a resolution of 640x480 pixels. After that version, many revisions have been introduced. The most common version of VGA is Super VGA (SVGA). It allows for resolutions greater than 640x480, such as 800x600 or 1024x768.