XESS XStend XS40, Manual

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Displaying Switch Settings on the XStend Board LEDs
This example creates a circuit that displays the settings of the DIP switches on the LEDs
and LED digits of the XStend and XS Boards. The particular set of LEDs, which is
activated, is selected by the SPARE and RESET pushbuttons. The VHDL code for this
example is shown in
Listing 13 .
The steps for compiling and testing the design using an XS40 combined with an XStend
Board are as follows:
n Synthesize the VHDL code in the SWTCH40\SWITCHES.VHD file for an XC4005XL
FPGA.
n
Compile the synthesized netlist using the SWTCH40.UCF constraint file ( Listing 14 ).
n Mount an XS40 Board in the XStend Board and attach the downloading cable from
the XS40 to the PC parallel port. Apply 9VDC though jack J9 of the XS40. Place
shunts on jumpers J4, J7, and J8 of the XStend Board to enable the LED displays.
Remove the shunt on jumper J17 to keep the XStend codec serial output from
interfering with the DIP switch logic levels.
n Download the SWTCH40.BIT file into the XS40/XStend combination with the
command:
XSLOAD SWTCH40.BIT
.
n Set the DIP switches and press the SPARE and RESET pushbuttons. Observe the
results on the LEDs.
n The steps for compiling and testing the design using an XS95 combined with an
XStend Board are as follows:
n Synthesize the VHDL code in the SWTCH95\SWITCHES.VHD file for an XC95108
CPLD.
n Compile the synthesized netlist using the SWTCH95.UCF constraint file ( Listing 15 ).
n Generate an SVF file for the design.
n Mount an XS95 Board in the XStend Board and attach the downloading cable from
the XS95 to the PC parallel port. Apply 9VDC though jack J9 of the XS95. Place
shunts on jumpers J4, J7, and J8 of the XStend Board to enable the LED displays.
Chapter
4
Example Designs