Digilent 410-258P-KIT - Manual (Page 5)

Anvyl Reference Manual
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VGA
The Anvyl provides a 12bit VGA interface which allows up to 4096 colors displayed on a standard
VGA Monitor. The five standard VGA signals Red, Green, Blue, Horizontal Sync (HS), and Vertical
Sync (VS) are routed directly from the FPGA to the VGA connector. There are four signals routed
from the FPGA for each of the standard VGA color signals resulting in a video system that can
produce 4,096 colors. Each of these signals has a series resistor that when combined in the circuit,
form a divider with the 75-ohm termination resistance of the VGA display. These simple circuits
ensure that the video signals cannot exceed the VGA-specified maximum voltage, and result in color
signals that are either fully on (.7V), fully off (0V) or somewhere in between.
Fig. 2. VGA interface.
Fig. 3. HD DB-15 connector, PCB hole pattern, pin assignments, and color-signal mapping.