Specifications
3.2
OPERATION
WITH
DOS
The
Little
Board/PC
and
its ROM-BIOS have
been
designed
to
allow the use
of
IBM PC-
DOS,
Microsoft MS-DOS,
or
Digital Research DR-DOS, versions 2.x
or
3.x,
and
PC-DOS
or
MS-DOS
version 4.01,
as
the
board's
operating system. Throughout this
chapter,
the
term
"DOS" will
be
used
to refer
to
any
of
these operating systems, except
in
cases where a differ-
ence
in
operation exists.
Caution
Many
variations
of
MS-DOS
exist which have
been
cus-
tomized
for
operation
on
specific
computer
systems.
These
cannot
be
expected
to
function
properly
on
the
Little
Board/PC.
and
should not
be
used. Use "IBM PC-
DOS".
or
use
the
"generic IBM compatible" version
of
MS-
DOS
supplUddirectly by
Microsoft
011
an
OEM basis.
if
you
do
not
choose
to
use
the
DR-DOS
operating
system
sup-
plied by Ampro.
In
addition
to
supporting
the
standard
DOS
functions, the board's ROM-BIOS internal func-
tions
are
highly compatible with those
of
the "standard PC", allowing software which makes
direct
ROM-BIOS
calls to function properly, without modification.
Nearly all
of
the
hardware ports and controllers
on
the Little
Board/PC
are
identical
in
func-
tion
with
those
of
the
"standard PC".
This
includes
the
floppy
controller,
keyboard
port,
speaker port,
PC
serial port, parallel printer port, counter/timers,
and
interrupt controller.
In
addition, the optional
Ampro
MinModule/VGA, MiniModule/EGA, MinModule/CGA,
and
MiniModule/LCD
onboard
display
controller
modules offer
the
most
popular
PC-
compatible video modes: VGA,
EGA,
CGA, MDA, and Hercules monochrome graphics
on
either
CRT
or
LCD
displays.
Although
the
board's
DMA
controller
is
not
totally compatible, special logic
in
the
board's
ASIC devices in combination with support within the board's ROM-BIOS result
in
software
compatibility.
The
board's
8250-based "PC
Serial
Port"
can
be
jumpered
as
either
the
DOS
"COM!"
or
"COM2" port.
The
Parallel Printer
port
can
be
jumpered as either "LPTl"
or
"LPT2". These
devices,
as
well as the keyboard
and
speaker ports,
are
supported
by
the
ROM-BIOS
in
a PC-
compatible manner.
The
board's
non-compatible "V40
Serial
Port"
can
be
substituted
as a system console
port
(using
the
Ampro
CONDRVR
device driver)
command,
for applications which
can
use a
serial device for keyboard
and
display.
Refer
to
the
discussion
of
"Serial
Console
Option,"
presented
later
in
this chapter.
The
DOS
and
ROM-BIOS time-of-day clocks
are
supported
in
the usual manner. They can
be
initialized automatically
by
a utility
to
the
value stored in the optional battery-backed clock
module
on
system reset
or
powerup.
Refer
to the documentation supplied with the battery-
backed clock for further details.
3-2