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Altera DDR Timing Wizard User Manual

Page 38

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2–26

Altera Corporation

DDR Timing Wizard User Guide

November 2007

Entering and Editing Inputs to the DTW

1

The default TimeQuest Timing Analyzer clocking names
are shown in

Figure 2–19

. If you are using Classic Timing

Analyzer, the default clocking names for the system PLL
are:

ddr_pll_stratixii:g_stratixpll_ddr_pll_inst

|altpll:altpll_component|_clk

n

where n denotes the PLL output counter number.

Clicking on a field in this page highlights the location of that field in
the design schematic in the bottom of the page. For example, if you
click on the resync_cycle field as shown in

Figure 2–20

, the path

from the system PLL to the Resync DFF1 is highlighted to show
where the resync_cycle information is used. The DTW shows a
different schematic if the interface is using 1-PLL mode.

1

You can use the highlights as a guide when you must enter
each field manually. The design schematic varies
depending on the interface mode, whether you are using
DQS, or whether you are using 2-PLL (with the fedback
PLL) or 1-PLL mode. This example design uses DQS with
2-PLL implementation.