Altera DQ (ALTDQ) - Manual (Page 30)

Page 30 Ports and Parameters
DQ (ALTDQ) and DQS (ALTDQS) Megafunctions November 2010 Altera Corporation
DLL_USE_UPNDNINCLKENA String No
Specifies whether to use the dll_upndninclkena port as a clock
enable for DLL counter. The values are TRUE or FALSE. If omitted,
the default value is FALSE. If the DLL_USE_UPNDNINCLKENA
parameter is set to TRUE, the DLL_USE_UPNDNINCLKENA
parameter overrides DLL control of the clock enable for DLL
counter.
(1)
DQS_CTRL_LATCHES_
ENABLE
String No
Enables or disables latches for DQS delay buffer control signals.
The values are TRUE or FALSE. If omitted, default is TRUE. If the
DLL_DELAYCTRL_MODE
parameter is set to NONE, the
DQS_CTRL_LATCHES_ENABLE parameter cannot be set to TRUE.
(1)
DQS_DELAY_CHAIN_
LENGTH
Integer No
Specifies number of delay buffers used in DQS delay chain. The
values are 0, 1, 2, 3, or 4. If omitted, the default value is 3.
(1)
DQS_EDGE_DETECT_
ENABLE
String No
Specifies whether edge detection prevents updates to DQS delay
buffer control latches during a DQS transition. The values are TRUE
or FALSE. If omitted, default is FALSE. If
DQS_CTRL_LATCHES_ENABLE
parameter is set to FALSE,
DQS_EDGE_DETECT_ENABLE parameter cannot be set to TRUE. (1)
DQS_USE_DEDICATED_
DELAYCTRLIN
String No
Specifies whether the DLL directly feeds the DQS delay buffer
control signals. The values are TRUE or FALSE. If omitted, default
is FALSE. If the DLL_DELAYCTRL_MODE parameter is set to NONE,
the DQS_USE_DEDICATED_DELAYCTRLIN parameter cannot be set
to TRUE. If the DQS_CTRL_LATCHES_ENABLE parameter is set to
TRUE
, the DQS_USE_DEDICATED_DELAYCTRLIN parameter cannot
be set to FALSE. (1)
DQSN_MODE String No
Specifies whether to use the dqsb_padio port. The values are
NONE
, INPUT, OUTPUT, or BIDIR. If omitted, default is NONE. If the
DQS_CTRL_LATCHES_ENABLE parameter is set to TRUE, the
DQS_USE_DEDICATED_DELAYCTRLIN parameter cannot be set to
FALSE . (1)
GATED_DQS String No
Specifies whether to AND DQS output with a register clocked by
delayed DQS signal. The values are TRUE or FALSE. If omitted,
default is FALSE. The GATED_DQS parameter can only be used
when the DQSN_MODE parameter is set to NONE or OUTPUT.
(2)
DELAY_CHAIN_MODE String No
Specifies delay chain mode. (1) There are two modes:
■ DLL Feedback Loop Counter used to control the DQS/nDQS
delay chains
■ No DLL used
DQS_DELAY_CHAIN_
SETTING
Integer No
Specifies value of delay chain. The legal values range from 0
through 63. The DQS_DELAY_CHAIN_SETTING parameter is
ignored if the HAS_DQS_DELAY_REQUIREMENT parameter is
specified to TRUE.
(3)
DQS_DELAY_REQUIREMENT String No
Specifies delay requirement value. This parameter is available only
if the HAS_DQS_DELAY_REQUIREMENT parameter is specified to
TRUE
.
HAS_DQS_DELAY_
REQUIREMENT
String No
Specifies whether to use a delay requirement. The values are TRUE
or FALSE. If omitted, the default value is FALSE.
Table 19. ALTDQS Megafunction Parameters (Part 3 of 4)
Parameter Type Required Description