Suspend Switch - Xilinx Spartan-3A User Manual

Chapter 2: Switches, Buttons, and Rotary Knob

SUSPEND Switch

The SUSPEND slide switch, shown in
SUSPEND input pin. If Suspend mode is enabled in the FPGA application, then the FPGA
enters Suspend mode whenever the switch is set to "SUSPEND." If the switch is then
changed back to "RUN," then the FPGA resumes operation from the state before it entered
Suspend mode. Likewise, if Suspend mode is enabled, then the AWAKE pin is reserved to
indicate when the FPGA is in Suspend mode. See
To enable Suspend mode, add the configuration string shown in
constraints file (UCF). If Suspend mode is not enabled in the application, then the
SUSPEND switch has no affect on the design and the AWAKE pin is available as a general-
purpose I/O.
For more information on Suspend mode, see the following application note:
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26
NET "SW<0>" LOC = "V8" |
NET "SW<1>" LOC = "U10"|
NET "SW<2>" LOC = "U8" |
NET "SW<3>" LOC = "T9" |
Figure 2-2: UCF Constraints for Slide Switches
CONFIG ENABLE_SUSPEND =
Figure 2-4: UCF Constraints to Enable Suspend Mode
XAPP480: Using Suspend Mode in Spartan-3 Generation FPGAs
www.xilinx.com/bvdocs/appnotes/xapp480.pdf
www.xilinx.com
IOSTANDARD = LVTTL |
IOSTANDARD = LVTTL |
IOSTANDARD = LVTTL |
IOSTANDARD = LVTTL |
Figure 2-3, connects directly to the FPGA's
"AWAKE LED," page
Figure 2-3: Suspend Switch
"FILTERED" ;
Spartan-3A/3AN Starter Kit Board User Guide
PULLUP ;
PULLUP ;
PULLUP ;
PULLUP ;
32.
RUN
SUSPEND
UG334_c2_03_052407
Figure 2-4 to the user
UG334 (v1.0) May 28, 2007
R