Specifications

EPC-8A Hardware Reference
18
About Drive Letter Assignment
The BIOS determines the boot device algorithmically. First it determines where the floppy
drive fits into the sequence; however, for simplicity here, assume no A: drive. The BIOS
starts by determining if an IDE controller is enabled. If so, this becomes the C: drive and is
expected to be the boot device.
The BIOS searches memory for enabled mass-storage devices, and builds a device table.
The first device it finds is the C: drive, and thus the boot device. The second device found
is the D: drive; only two physical drives are supported.
If an IDE drive is specified in the BIOS setup, it becomes the C: drive. Next, the BIOS
looks for BIOS extensions at addresses C8000, CC000, D000, D4000, D8000 and DC000
for more devices, up to the maximum of two.
There are many different boot options. Two supported directly on the EPC-8A hardware
and BIOS are booting from a Flash ROMdisk and booting from a VME ROM disk. For
more information on booting from a VME ROMdisk or a Flash ROMdisk, refer to setups
in the Advanced Menu and Appendix G, XFORMAT Software.
Floppy check Enables or disables the floppy drive search during the boot. To
speed up booting, you can disable the floppy check. It is still
possible to boot from the A: drive even with the floppy check
disabled. The default is to enable the floppy check.
Summary screen Enables or disables a summary of the system configuration,
which displays before the operating system starts to load. To
save time, you can disable the summary screen. The default is
to enable the summary screen display.
Field Description