How to add the New device in Vivado HLS

1. Download the Board file from https://github.com/Digilent/vivado-boards/archive/master.zip.
2. unzip the folder.
3. save all boards or required one in C:\Xilinx\Vivado\2018.2\data\boards\board_files

Now for Vivado_HLS

 paste the following line (if you are working with Zybo7-"xc7z010clg400") in the file VivadoHls_boards.xml at
C:\Xilinx\Vivado\2018.2\common\config

<board name="Zybo" display_name="Zybo" family="zynq" part="xc7z010clg400-1"  device="xc7z010" package="clg400" speedgrade="-1" vendor="digilentinc.com" />


you can modify this line as per your board. 

Fourier Transform, Fourier Series, and frequency spectrum