1. Create a new RTL project called "leddec" with new source file "leddec" and a constraint file "leddec"
2. Added Nexys board.
3. Run synthesis, run implementation, open implemented design, generate bitstream, open hardware manager, and program device.
4. Slider switches 6 and 7 to determine which dsiplay is illuminated
5. Slider switches 0, 1, 2, and 3 to select the value of 4-bit hex digit.
Build a 4-bit counter to display a hex character
1. Create a new project called hexcounter in Vivado, add "leddec" source file, create two new source files "counter" and "hexcount" and constraint file "hexcount".
2. Run synthesis, run implementation, open implemented design, generate bitstream, open hardware manager, and program device.
3. The least significant 7-segment decoder counts cycles from 0 to F