3-13
BIOS Setup
Read Preamble value
W hen the
User Config mode
is set to [Manual], the field is adjustable. It
specifies the time prior to the max-read DQS-return when the DQS receiver
should be turned on. This is specified in units of 0.5ns. The controller needs to
know when to enbale its DQS receiver in anticipation of the DRAM DQS driver
truning on for a read. The controller will disable its DQS receiver until the read
preamble time and then enable its DQS receiver while the DRAM asserts DQS.
Setting options: [2ns] ~ [9.5ns].
Async Latency value
When the
User Config mode
is set to [Manual], the field is adjustable. This field
should be loaded with 4-bit value equal to th e maximum asynchronous latency
in the DRAM read round-trip loop. Setting options: [2ns] ~ [11ns].
MTRR M apping Mode
This setting controls the MTRR mapping mode. To install the W inXP64, this
setting should be set to [Continuous]. Setting options: [Continuous], [Discrete].
