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nexys_vga:refmanual [2015/09/09 17:19] – Marthanexys_vga:refmanual [2015/09/09 17:20] (current) – [VGA Port] Martha
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 The Nexys VGA Module interfaces with the Nexys board via the 16 pin header at J8 and connects to a VGA monitor using a standard 15 pin VGA cable. The Nexys VGA Module interfaces with the Nexys board via the 16 pin header at J8 and connects to a VGA monitor using a standard 15 pin VGA cable.
  
-{{ :nexys_vga:block_diagram.png?500 |Nexys VGA Block Diagram}}+{{ :nexys_vga:block_diagram.png?300 |Nexys VGA Block Diagram}}
  
 ===== Functional Description ===== ===== Functional Description =====
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 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. 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.
  
-{{ :nexys_vga:connector.png?500 |HD DB-15 connector, PCB hole pattern, pin assignments, and color-signal mapping}}+{{ :nexys_vga:connector.png?600 |HD DB-15 connector, PCB hole pattern, pin assignments, and color-signal mapping}}
  
 VGA signal timings are specified, published, copyrighted and sold by the VESA organization (www.vesa.org). The following VGA system timing information is provided as an example of how a VGA monitor might be driven in 640 by 480 mode. For more precise information, or for information on higher VGA frequencies, refer to documentation available at the VESA website. VGA signal timings are specified, published, copyrighted and sold by the VESA organization (www.vesa.org). The following VGA system timing information is provided as an example of how a VGA monitor might be driven in 640 by 480 mode. For more precise information, or for information on higher VGA frequencies, refer to documentation available at the VESA website.