Ucf Location Constraints; Related Resources - Xilinx Spartan-3A User Manual

R
A separate counter tracks the vertical timing. The vertical-sync counter increments with
each HS pulse, and decoded values generate the VS signal. This counter tracks the current
display row. These two continuously running counters form the address into a video
display buffer. For example, the on-board DDR2 SDRAM provides an ideal display buffer.
No time relationship is specified between the onset of the HS pulse and the onset of the VS
pulse. Consequently, the counters can be arranged to easily form video RAM addresses or
to minimize decoding logic for sync pulse generation.

UCF Location Constraints

Figure 6-4
assignment, the I/O standard used, the output slew rate, and the output drive current.

Related Resources

Refer to the following links for additional information:
•
•
Spartan-3A/3AN Starter Kit Board User Guide
UG334 (v1.0) May 28, 2007
provides the UCF constraints for the VGA display port, including the I/O pin
NET "VGA_R<3>" LOC = "C8" |
NET "VGA_R<2>" LOC = "B8" |
NET "VGA_R<1>" LOC = "B3" |
NET "VGA_R<0>" LOC = "A3" |
NET "VGA_G<3>" LOC = "D6" |
NET "VGA_G<2>" LOC = "C6" |
NET "VGA_G<1>" LOC = "D5" |
NET "VGA_G<0>" LOC = "C5" |
NET "VGA_B<3>" LOC = "C9" |
NET "VGA_B<2>" LOC = "B9" |
NET "VGA_B<1>" LOC = "D7" |
NET "VGA_B<0>" LOC = "C7" |
NET "VGA_HSYNC" LOC = "C11" |
NET "VGA_VSYNC" LOC = "B11" |
Figure 6-4: UCF Constraints for VGA Display Port
VESA
www.vesa.org
VGA timing information
www.epanorama.net/documents/pc/vga_timing.html
www.xilinx.com
UCF Location Constraints
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
IOSTANDARD = LVTTL | DRIVE
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
= 8 | SLEW = FAST ;
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