Advantech SOM-5899, User Manual

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53 SOM-5899 User Manual
Chapter 3
A
MI BIOS
Feature Options Description
CSM Support
Disabled
Enabled
Enable/Disable CSM Support.
Gate A20
Active Upon Request
Always
UPON REQUEST - GA20 can be dis-
abled using BIOS services. ALWAYS -
do not allow disabling GA20; this
option is useful when any RT code is
executed above 1MB.
INT19 Trap
Response Immediate
Postponed
BIOS reaction on INT19 trapping by
Option ROM: IMMEDIATE - execute
the trap right away; POSTPONED -
execute the trap during legacy boot.
Boot option
filter
UEFI and Legacy
Legacy only
UEFI only
This option controls Legacy/UEFI
ROMs priority
Network
Do not launch
UEFI
Legacy
Controls the execution of UEFI and
Legacy PXE OpROM
Storage
Do not launch
UEFI
Legacy
Controls the execution of UEFI and
Legacy Storage OpROM
Video
Do not launch
UEFI
Legacy
Controls the execution of UEFI and
Legacy Video OpROM
Other PCI
Devices
Do not launch
UEFI
Legacy Determines OpROM execution policy
for devices other than Network, Stor-
age, or Video
Note! CSM: The Compatibility Support Module (CSM) is a component of the
UEFI firmware that provides legacy BIOS compatibility by emulating a
BIOS environment, allowing legacy operating systems and some option
ROMs that do not support UEFI to still be used.
CSM also provides required legacy System Management Mode (SMM)
functionality, called CompatibilitySmm, as an addition to features pro-
vided by the UEFI SMM. This is optional and highly chipset- and plat-
form-specific. An example of such a legacy SMM functionality is
providing USB legacy support for keyboard and mouse, by emulating
their classic PS/2counterparts.