HW-SPAR3-SK-UNI-G Xilinx Inc, HW-SPAR3-SK-UNI-G Datasheet - Page 23

• Manufacturer Part Number: HW-SPAR3-SK-UNI-G
• Description: KIT STARTER SPARTAN-3
• Manufacturer: Xilinx Inc
• Series: Spartan-3r
• Type: FPGA Configurationr

Specifications of HW-SPAR3-SK-UNI-G

• Contents: Board, Cable, Software, Datasheets and User Manual
• For Use With/related Products: Spartan-3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 122-1521

Signal Timing for a 60Hz, 640x480 VGA Display
Spartan-3 FPGA Starter Kit Board User Guide
UG130 (v1.2) June 20, 2008
time
HS
Current
through the
horizontal
deflection
coil
"back porch"
same signal timings as CRT displays. Consequently, the following discussion pertains to
both CRTs and LCD displays.
Within a CRT display, current waveforms pass through the coils to produce magnetic
fields that deflect electron beams to transverse the display surface in a “raster” pattern,
horizontally from left to right and vertically from top to bottom. As shown in
information is only displayed when the beam is moving in the “forward” direction—left to
right and top to bottom—and not during the time the beam returns back to the left or top
edge of the display. Much of the potential display time is therefore lost in “blanking”
periods when the beam is reset and stabilized to begin a new horizontal or vertical display
pass.
The size of the beams, the frequency at which the beam traces across the display, and the
frequency at which the electron beam is modulated determine the display resolution.
pixel 0,0
pixel 479,0
Stable current ramp: Information is
displayed during this time
Figure 5-2: CRT Display Timing Example
640 pixels are displayed each
time the beam traverses the screen
Horizontal display time
VGA Display
Horizontal sync signal
sets the retrace frequency
www.xilinx.com
Total horizontal time
pixel 479,639
pixel 0,639
retrace time
"front porch"
"back porch"
Retrace: No
information
is displayed
during
this time
UG130_c5_02_051305
Figure
5-2,
23
R