Altera DQ (ALTDQ) Uživatelský manuál stáhnout pdf (Strana 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

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

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

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

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

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

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

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

, or

. If omitted, the default value is

. (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

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

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

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

. If omitted, default is

. 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

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

1 2 ... 24 25 26 27 28 29 30 31

Komentáře k této Příručce

Žádné komentáře

Altera DQ (ALTDQ) Uživatelský manuál Strana 29

Komentáře k této Příručce

Související produkty a manuály pro Měřící nástroje Altera DQ (ALTDQ)