Boot With Pnp Os; Isa Shared Memory Size - NEC POWERMATE PRO150 Manual

If Use ICU is selected, the BIOS will depend on run-time software to ensure
that there are no conflicts between ISA boards with Plug and Play
capabilities and those without. Only Boot With PnP OS will be visible.

Boot with PnP OS

Enables the PC to boot with an operating system capable of managing Plug
and Play add-in cards. The options are None, Other, and Windows 95. The
default is Windows 95.

ISA Shared Memory Size

Enables you to specify a range of memory addresses that will be directed to
the ISA bus rather than on-board memory. The options are Disabled, 16 KB,
32 KB, 48 KB, 64 KB, 80 KB, and 96 KB. The default is Disabled. If this is set
to Disabled, the ISA Shared Memory Base Address (described below) will
not be visible.
This field should be set to Enabled only when a non Plug and Play ISA card
(legacy card) that requires non-ROM memory space is used. LAN cards
that have on-board memory buffers are one example of this; video capture
cards that have video buffer memory are another.
By default, allocation of upper memory is as follows: memory from C0000-
C7FFF is automatically shadowed. (This memory range is typically
reserved for video BIOS.) Memory from C8000-DFFFFh is initially
unshadowed. The BIOS scans this range for any ISA expansion card BIOSes
that may be present and notes their location and size. The BIOS will then
autoconfigure the PCI and Plug and Play devices, shadowing the ROM
requirements (other than video) into the area above E0000h until that area is
full. It will then assign additional PCI and Plug and Play expansion cards to
the area between C8000h and DFFFFh. If an ISA legacy card has non-ROM
memory requirements, the autoconfigure routine may write into an area
that is needed by the ISA expansion card. The ISA Shared Memory Size
parameter signifies the autoconfigure routine that this block of memory is
reserved and should not be shadowed.
Shadowing is a technique that copies a block of memory from an add-in
card's ROM to the same address in system DRAM memory. This provides
faster access and achieves higher performance.
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Using the Setup Program