IBM Personal System/2 50 - Hardware Compatibility

Type
2
Serial
Port
Controller
The
Model!
50
does
not
support
FIFO
mode
operations
even
if
a
Type
2
serial
controller
is
installed.
Do
not
enable
FIFO
operations
if
the
model/submodel
byte
is
hex
FC/04.
The
serial
controller
on
some
Type
2
system
boards
does
not
respond
the
same
as
other
Personal
System/2
products.
After
the
initial
transmitter-holding-register-empty
interrupt,
rewriting
bit
1
of
the
Interrupt
Enable
register
as
a
1
will
not
reissue
an
interrupt.
The
interrupt
is
generated
only
when
the
Transmitter
Holding
register
becomes
empty.
Hardware
Compatibility
The
Model
50
maintains
many
of
the
interfaces
used
by
the
IBM
Personal
Computer
AT.
In
most
cases,
command
and
status
organization
of
these
interfaces
is
maintained.
The
functional
interfaces
for
the
Personal
System/2
products
are
compatible
with
the
following
interfaces:
©
The
Intel”
8259
interrupt
controllers
(without
edge
triggering).
*
The
Intel
8253
timers
driven
from
1.193
MHz
(timer
0
and
2
only).
The
Intel
8237
DMA
controller-address/transfer
counters,
page
registers
and
status
fields
only.
The
Command
and
Request
registers
are
not
supported.
The
rotate
and
mask
functions
are
not
supported.
The
Mode
register
is
partially
supported.
*
Generally
compatible
with
the
NS16450
serial
communications
controller.
¢
The
Intel
8088,
8086,
and
80286
microprocessors.
*
The
Intel
8272
diskette
drive
controller.
The
Motorola”
MC146818
Time
of
Day
Clock
command
and
status
(CMOS
reorganized).
°
The
Intel
8042
keyboard
port
at
address
hex
0060.
Display
modes
supported
by
the
IBM
Monochrome
Display
and
Printer
Adapter,
the
IBM
Color/Graphics
Monitor
Adapter,
and
the
IBM
Enhanced
Graphics
Adapter.
ee
“Intel
is
a
trademark
of
the
Intel
Corporation.
*
Motorola
is
a
trademark
of
Motorola,
Incorporated.
3-28
Model
50
System
Board
—
October
1990