Siemens SIMATIC 627B, Руководство по эксплуатации

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Detailed descriptions
16.4 BIOS Setup
SIMATIC Box PC 627B
186
Operating Instructions, 06/2008, A5E00927393-02
LBA Mode
Control
The "Enabled" setting at the "LBA Mode Control" (enabled, disabled) option means
that hard disk capacities greater than 528 MB are supported. The value depends on
the drive and should only be set by way of "Auto" setting at the "Type" field.
The type of access to the drive is determined in the 32-bit I/O field
Disabled
16-bit access (default)
32-bit I/O
Enabled 32-bit access
Transfer
Mode or Ultra
DMA Mode
Define the data transmission rate of the interface in these fields. The value depends
on the drive and should only be set by way of "Auto" setting at the "Type" field.
Exit the submenu by pressing ESC.
"Memory Cache" field
The following shortcut menu appears when you select the option "Memory cache" in the
main menu:
Figure 16-9 "Memory Cache" field
The cache is a high-speed memory buffer between the CPU and memory (DRAM).
Repeated memory access operations are executed in the faster cache, and not in the main
memory, provided the feature is enabled. In some cases it may be necessary to disable the
cache for certain types of hardware and software because intentional program runtimes or
delay times may be prevented by the fast cache.
[Disabled] Cache is disabled
[Enabled] Cache is enabled