Altera DQ (ALTDQ) - Manual (Page 12)

Page 12 Getting Started
DQ (ALTDQ) and DQS (ALTDQS) Megafunctions November 2010 Altera Corporation
Page 8 of the ALTDQS MegaWizard Plug-In Manager is the DQS/nDQS Delay Chain
page.
Table 7 on page 12 describes options available on page 8 of the ALTDQS
megafunction.
Page 9 of the MegaWizard Plug-In Manager is the EDA page. This page lists the
simulation model files needed to simulate the generated design files. On this page,
you can enable the Quartus II software to generate a synthesis area and timing
estimation netlist for this megafunction for use by third-party tools.
Page 10 of the MegaWizard Plug-In Manager is the Summary page. On this final
page, the wizard displays a list of the types of files to be generated. The automatically
generated Variation file contains wrapper code in the language you specified on page
2a. On this page, you can specify additional types of files to be generated. Choose
from the AHDL Include file (.inc), VHDL component declaration file,
Table 7. DQS/nDQS Delay Chain Port Settings
Option Description
Device Supported
Cyclon
e
II
Cyclone
III, Cyclone
III
G
X
, Cyclone
III
LS
St
ratix, Strat
ix GX,
St
ratix
II,
Str
a
tix
II
GX,
Arria
GX,
HardCopy
II
Offset options for DQS/nDQS
delay chain
Allows tuning of the DQS delay chain. Depending on
settings from wizard page 4, the offset applies either a
coarse or fine delay.
(1)
When a static delay is added, the value of delay is
equivalent to offset value multiplied by coarse or fine offset
buffer delay. If a dynamic delay is selected, a dll_offset
port is added to the megafunction. The unsigned integer
values on dll_offset port may then be added,
subtracted, or dynamically controlled with a dll_addsub
port by selecting one of the options. For static offset, the
value is added to the DLL feedback counter and output on
the dll_delayctrlout output bus. The legal integer
values are –63 to 63.
No No No Yes
Enable the latches for the DQS
delay chain setting
(2)
These latches ensure that the offset value is not changed
while the DQS transitions, and also determines whether the
DQS delay buffer control signals are latched or not.
No No No Yes
Create reset for the DLL If enabled, a reset input is added to clear the DLL. No No No Yes
Note to Table 7 :
(1) For more information, refer to Table 3 on page 7 .
(2) For more information about utilizing the offset, refer to AN550: Using the DLL Phase Offset Feature in Stratix II and HardCopy II Devices .