Altera ALTDLL - Manual (Page 107)

A–6 Appendix A: Clear Box Generator
Clear Box Generator Options
ALTDLL and ALTDQ_DQS Megafunctions User Guide © February 2012 Altera Corporation
Table A–3 summarizes the Clear Box parameters for the ALTDQ_DQS megafunction
to configure the DQS input path.
Table A–3. Megafunction Parameters to Configure DQS Input Path (Part 1 of 4)
Parameter Name
Optional/
Required Default Legal Values Description
USE_DQS_INPUT_DELAY_CHAIN Optional FALSE FALSE, TRUE Instantiates
DQS_INPUT_DELAY_CHAIN if
TRUE .
USE_DQS_DELAY_CHAIN Optional FALSE FALSE, TRUE Instantiates DQS_DELAY_CHAIN if
TRUE .
USE_DQS_ENABLE Optional FALSE FALSE, TRUE Instantiates DQS_ENABLE if TRUE .
USE_DQS_ENABLE_CTRL Optional FALSE FALSE, TRUE Instantiates DQS_ENABLE_CTRL if
TRUE .
USE_DQSBUSOUT_DELAY_CHAIN Optional FALSE FALSE, TRUE Instantiates
DQSBUSOUT_DELAY_CHAIN if
TRUE .
USE_DQSENABLE_DELAY_CHAIN Optional FALSE FALSE, TRUE Instantiates
DQSENABLE_DELAY_CHAIN if
TRUE .
DQS_INPUT_FREQUENCY Optional UNUSE
D — This parameter is set to the frequency
of the DQS strobe/clock input
expressed as a string and, if
is not set to
0 , and
is not set to
FALSE , this needs to match the
input_frequency parameter of the DLL
feeding the
delayctrlin[5..0]
input. This is an optional field and
defaults to
UNUSED .
DQS_DELAY_CHAIN_
DELAYCTRLIN_SOURCE
Optional Core,
DLL DLL This parameter is the Gray-coded delay
chain setting for the DQS read path.
This is an optional input and defaults to
GND . You can ignore this input if the
parameter is set to
FALSE and is set to
0 . You can feed this input by the
delayctrlout output of a DLL or the
core. This input does not need to
match the polarity of its source and can
be inverted (unless fed by the
delayctrlout output of a DLL).