Advantech DVMB-554E, Руководство пользователя

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Figure 3.5: Advanced chipset features screen (b)
Note: DRAM default timings have been carefully cho-
sen and should ONLY be changed if data is
being lost. Please first contact technical sup-
port.
3.5.1 DRAM Timing Selectable
This item allows you to control the DRAM speed. The selections are
“Manual” or “By SPD”.
3.5.2 CAS Latency Time
When DRAM Timing Selectable is set to [Manual], this field is adjust-
able. This controls the CAS latency, which determines the time interval
between SDRAM starting a read command and receiving it. The options
are [3T], [4T], [5T], and [Auto].
3.5.3 DRAM RAS# to CAS# Delay
When DRAM Timing selectable is set to [Manual], this field is adjust-
able. When DRAM is refreshed, the rows and columns are addressed sep-
arately. This setup item allows user to determine the timing of the
transition from RAS (row address strobe) to CAS (column address strobe).
The less the clock cycles are, the faster the DRAM speed is. Set- ting
options are [2T] to [5T], and [Auto].