4 ras# to cas# delay (trcd), 5 write recovery time (twr), 6 row refresh cycle (trfc) – Avalue ESM-QM57 User Manual

Page 68: 7 write to read delay (twtr), 8 active to active (trrd), 9 read cas# precharge (trtp)

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ESM-QM57

68 ESM- QM57 User

’s Manual


3.6.3.1.4 RAS# to CAS# Delay (tRCD)

This option allows you to insert a delay between the RAS (Row Address Strobe) and CAS

(Column Address Strobe) signals. This delay occurs when the SDRAM is written to, read

from or refreshed. Naturally, reducing the delay improves the performance of the SDRAM

while increasing it reduces performance.

3.6.3.1.5 Write Recovery Time (tWR)

It shows the delay (in clocks cycles) that must elapse after the completion of a valid write

operation. The shorter the delay, the earlier the bank can be precharged for another

read/write operation.

3.6.3.1.6 Row Refresh Cycle (tRFC)

Determines the number of clock measured from a Refresh command (REF) until the first

Activate command (ACT) to the same rank

3.6.3.1.7 Write to Read Delay (tWTR)

This constitutes the minimum number of clock cycles that must occur between the last valid

write operation and the next read command to the same internal bank of the DDR device.

3.6.3.1.8 Active to Active (tRRD)

The minimum time interval between successive ACTIVE commands to the different banks

is defined by tRRD.

3.6.3.1.9 Read CAS# Precharge (tRTP)

Number of clocks that are inserted between a read commands to a row pre-charge

command to the same rank.

Item

Option

Description

Low MMIO Align

64M,

1024M

This option will determine Low

MMIO resources align.

Initiate Graphic Adapter

IGD,

PCI/IGD ; PCI/PEG,

PEG/IGD ; PEG/PCI

This item allows you to select

which graphics controller to use

as the primary boot device.

Graphics Turbo IMON Current

Min= 14, Max= 31

Graphics turbo IMON current

values supported.

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