Altera DQ (ALTDQ) - Manual (Page 29)

Ports and Parameters Page 29
November 2010 Altera Corporation DQ (ALTDQ) and DQS (ALTDQS) Megafunctions
DQS_OUTPUT_SYNC_RESET String No
Specifies whether the dqs_sreset port clears, presets, or has no
effect on DQS output registers. The values are CLEAR, PRESET, or
NONE
. If DQS_OUTPUT_SYNC_RESET port is specified to CLEAR or
PRESET , dqs_sreset is required. If omitted, the default value is
NONE .
EXTEND_OE_DISABLE String No
Specifies whether to use second oe register. The values are TRUE
or FALSE. When the EXTEND_OE_DISABLE is set to TRUE, the
output drive is held at high impedance for an extra half clock cycle
when the oe port goes high.
INPUT_FREQUENCY String No Specifies frequency of DQS inputs and system reference clock.
NUMBER_OF_DQS Integer Yes Specifies number of DQS pins that are implemented.
SIM_INVALID_LOCK Integer No
Specifies number of half-cycles that DLL keeps signal locked after
a bad clock is detected. The default is 32 half-cycles.
SIM_VALID_LOCK Integer No
Specifies number of half-cycles required before the DLL locks onto
signal. The default value is 1.
TIE_OFF_DQS_OUTPUT_
CLOCK_ENABLE
String No
Specifies whether clock enable for output registers is tied-off (does
not affect the output registers). The values are TRUE or FALSE. If
omitted, the default value is FALSE.
TIE_OFF_DQS_OE_CLOCK_
ENABLE
String No
Specifies whether clock enable for oe registers that are controlled
by the outclkena port should be tied off. The values are TRUE or
FALSE
. If omitted, the default value is FALSE.
DELAY_BUFFER_MODE String No
Specifies speed of DLL and DQS delay buffers. The values are LOW
or HIGH. If omitted, the default value is LOW.
(1)
DLL_DELAY_CHAIN_
LENGTH
Integer No
Specifies number of delay buffers used in DLL loop. The values are
0
, 1, 2, 3, or 4. If omitted, the default value is 3. (1)
DLL_DELAYCTRL_MODE String No
Specifies delay control mode used to feed DQS and DQSn delay
buffers. The values are NORMAL, NORMAL_OFFSET, OFFSET_ONLY,
or NONE. If omitted, the default value is NORMAL.
(1)
DLL_JITTER_REDUCTION String No
Enables or disables jitter reduction on the dll_delayctrlout
output ports. The values are TRUE or FALSE. If omitted, the default
value is TRUE.
(1)
DLL_OFFSETCTRL_MODE String No
Specifies DLL phase offset mode used with DQS delay buffer
control. The values are DYNAMIC_ADD, DYNAMIC_SUB,
DYNAMIC_ADDNSUB
, STATIC, or NONE. If omitted, the default value
is NONE. (1)
DLL_STATIC_OFFSET Integer No
Adds a value to the DLL feedback counter and output on the
dll_delayctrlout
output bus. The legal integer values are –63
to 63. If omitted, default is 0. If the DLL_OFFSETCTRL_MODE
parameter is set to a value other than STATIC, the
DLL_STATIC_OFFSET
parameter is ignored. (1)
DLL_USE_UPNDNIN String No
Specifies whether to use the dll_upndnin port to update the DLL
counter. The values are TRUE or FALSE. If omitted, default value is
FALSE
. If the DLL_USE_UPNDNIN parameter is set to TRUE,
DLL_JITTER_REDUCTION parameter must be set to FALSE. (1)
Table 19. ALTDQS Megafunction Parameters (Part 2 of 4)
Parameter Type Required Description