Xilinx Synthesis Technology User Guide

Command Line Mode
You can improve the readability of the xst.scr file, especially if you
use many options to run synthesis. You can place each option with its
value on a separate line, respecting the following rules:
• The first line must contain only the run command without any
options.
• There must be no empty lines in the middle of the command.
• Each line (except the first one) must start with a dash (-)
For the previously used command you may have the xst.scr file in the
following form:
run
-ifn watchvhd.vhd
-ifmt VHDL
-ofn watchvhd.ngc
-ofmt NGC
-p xcv50-bg256-6
-opt_mode Speed
-opt_level 1
Case 2: Each Design in a Separate File
For Case 2, each design block is located in a separate VHDL file.
1. Create a new directory, named vhdl_m.
2. Copy the following files from the ISEexamples\watchvhd
directory of the ISE installation directory to the newly created
vhdl_m directory.
♦ stopwatch.vhd
♦ statmach.vhd
♦ decode.vhd
♦ cnt60.vhd
♦ smallcntr.vhd
♦ hex2led.vhd
To synthesize the design, which is now represented by six VHDL
files, use the project approach supported in XST. A VHDL project file
contains a list of VHDL files from the project. The order of the files is
not important. XST is able to recognize the hierarchy, and compile
XST User Guide 8-17