Specifications

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There is a special case relating to VGA BIOS extensions. Before the TP400 BIOS
installs a VGA BIOS for the on-board graphics logic from within the Flash chip it first
examines the PC/104 and PC/104-Plus buses, looking for any other VGA BIOS that
may be present. If another VGA BIOS exists (because the user is using another
graphics controller, or because the TCDEVPLUS’s on-board VGA controller is
enabled) then this other VGA BIOS and its associated VGA controller hardware may
used, depending on BIOS Setup settings.
If a second graphics controller is present then there are three options. In the first
option the Geode GX1 graphics controller is disabled and the external adapter is
used. In the second case the external adapter is used as the "primary" controller, but
the Geode GX1 graphics controller is retained as a secondary controller, for use by
operating systems such as Windows 98 which support multiple screens. The third
option is for the Geode GX1 graphics controller to be used as the primary controller
and the external adapter is used as the secondary controller. The selection between
these choices is made by the Advanced / Multiple Monitor Support BIOS Setup menu.
6.3.3 The Flash File System BIOS Extension
The standard TP400 boards are shipped with a BIOS image that includes two BIOS
extensions. The second BIOS extension is the Flash File System BIOS extension.
The FFS BIOS Extension is 16k bytes in size and is located at address CC000h.
The Flash File System device allows the Flash memory to be configured as a disk
drive, as described in section 6.6.
The Flash File System is designed for MS-DOS and related operating systems. It is
likely that the Flash File System BIOS extension will not operate with some other
operating systems, and may need to be disabled.
The Flash File System BIOS extension can be enabled or disabled by a switch in the
BIOS setup menu. By default the FFS BIOS extension is disabled. You should format
the FFS as described in section 6.6 before enabling the Flash File System BIOS
extension.
The Flash File System driver will cause the Windows 95/98 disk system to run slowly.
This is because when the Flash File System is installed Windows 95 uses the 16-bit
DOS file system, rather than its faster 32-bit native file system. It is unlikely that
Windows 95/98 users will want to use the Flash File System, so these users should
disable the Flash File System BIOS extension.
6.4 MS-DOS AND OTHER OPERATING SYSTEMS
The TP400 will MS-DOS, Windows 95/98, Windows NT, Windows CE and should run
any other operating system that will run on a PC. The computer will boot MS-DOS
from a floppy disk, from a hard disk or from the Flash File System.
DSP Design can supply Microsoft’s MS-DOS operating system, and the ROM-DOS
operating system from Datalight. Bootleg copies of the operating system of course
may not be run on the TP400.