Advantech PCA-6184, Руководство пользователя

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3.5.1 DRAM Timing Selectable
This item allows you to control the DRAM speed. The Choice: Host-
Clock, CLK-33M.
3.5.2 CAS Letency Time
This controls the latency between DDR RAM read command and the
time that the data actually becomes available. Leave this on the default
setting.
3.5.3 Active to Precharge Delay
This item allows you to select the value in this field, depending on
whether the board has paged DRAMs or EDO (extended data output)
DRAMs. The Choice: EDO 50ns, EDO 60ns,Slow, Medium, Fast, Turbo.
3.5.4 DRAM RAS#-to-CAS Delay
In order to improve performance, certain space in memory is reserved for
ISA cards. This memory must be mapped into the memory space below
16MB. The Choice: 15M-16M, Disabled.
3.5.5 DRAM RAS# Precharge
This controls the idle clocks after issuing a precharge command to
SDRAM. Leave this on the default setting.
3.5.6 DRAM DATA Integrity Mode
Select the size of Accelerated Graphics Port (AGP) aperture. The aperture
is a portion of the PCI memory address range dedicated for graphics
memory address space. Host cycles that hit the aperture range are for-
warded to the AGP without any translation. The Choice: 4M, 8M, 16M,
32M, 65M, 128M, 256M.
3.5.7 Memory Frequency For Onboard UBS
This should be enabled if your system has a USB installed on the system
board and you want to use it. Even when so equipped, if you add a higher
performance controller, you will need to disable this feature. The choice:
Enabled, Disabled.
3.5.8 DRAM Read Thermal Mgmt
Select Enabled if your system contains a Universal Serial Bus (USB) con-
troller and you have a USB keyboard. The choice: Enabled, Disabled.
3.5.9 System BIOS Cacheable
Selecting Enabled allows caching of the system BIOS ROM at F0000h-
FFFFFh, resulting in better system performance. However, if any pro-
gram writes to this memory area, a system error may result. The choice:
Enabled, Disabled.