Altera DDR Timing Wizard - Manual (Page 19)

Altera Corporation 2–7
November 2007 DDR Timing Wizard User Guide
Getting Started
1
You do not need to perform Quartus II Analysis and Synthesis
the first time you run DTW as this has been done when running
the auto_add_ddr_constraints.tcl script. However, any
subsequent calls to the DTW must be preceded with a Quartus II
Analysis and Synthesis process, otherwise DTW will not be able
to read any changes to the design.
Import Flow for the Altera Legacy Memory Controller IP Core or
Recommended Data Path
When you use the Altera-provided data path, you can benefit by
importing the memory data path settings, which saves time because
parameters required by the DTW do not need to be filled in manually. If
you choose to create your own data path, you can find more information
about the DTW pages in
“Manual Flow for Other External Memory
Interfaces or Source Synchronous Systems” on page 2–14 .
The following procedure illustrates a DDR/DDR2 SDRAM interface
example, but the steps are identical for the QDRII+/QDRII SRAM or the
RLDRAM II interface. Before performing the following steps, be sure to
run the legacy controller MegaWizard auto_add_ddr_constraints.tcl
script and run Quartus II Analysis and Synthesis.
After launching the DTW, follow these steps to import the timing
parameters and pin names from the legacy controller MegaWizard:
1. On the first page of the DTW, you are prompted to create or edit a
.dwz
file. Opening the DTW allows you to make changes to the
saved .dwz file or to create a new .dwz file. This file contains all of
the parameters you enter in the DTW script.
Figure 2–3 shows the first page of the DTW software in which you
can specify the location for the .dwz file. The default name and
location for the file is:
< quartus_ii_project_directory>/ddr_settings.dwz
Ensure that the .dwz file points to the project directory that you are
working on. If you have un-archived the project, the .dwz file may
still be pointing to the old project directory. You can change the file
name and click Next.
1
The saved file name always defaults to ddr_setting.dwz.
Ensure that it is the file name you want to use. If you have
multiple memory controllers in a design, you must have a
unique .dwz file name for each controller.