IBM Personal System/2 50 User Manual

Device Type Features
Microprocessor -- 80286
24-bit address and 16-bit data interface
System
Timers
1
Channel
0
—
System
timer
Channel
2
—
Tone
generation
for
speaker
Channel 3 — Watchdog timer
ROM
Subsystem
--
128KB
(KB
=
1024
bytes)
RAM
Subsystem
--
Type
1
-
1MB
on
the
system
board
(MB = 1,048,576 Bytes)
Type
2
-
1MB
or
2MB
on
the
system
board
CMOS
RAM
---
64-byte
CMOS
RAM
with
Subsystem
real-time
clock/calendar
Battery backup
Video
Subsystem
1
Auxiliary
connector
on
the
channel
Analog output
256KB video memory
Audio
Subsystem
1
Driven
by:
- System-timer channel 2
- The ‘audio sum node’ signal.
DMA
Controller
1
Eight
independent
DMA
channels
Single or burst transfers and read verification
Interrupt
Controller
1
16
levels
of
system
interrupts
Interrupts
are level-sensitive
Keyboard/Auxiliary
1
Keyboard
connector
Device
Controller
Auxiliary
device
connector
Password security
Diskette Drive 1 Supports:
Controller
-
720KB
formatted
diskette
density
- 1.44MB formatted diskette density.
Serial
Controller
1,
2*
RS-232C
interface
Paraliei Controller
Micro Channel
Math Coprocessor
Socket
Programmable as serial port 1 or 2
Programmable as parallel port 1, 2, or 3
Supports bidirectional input and output
Four
channel
connectors
for
Type
3
adapters:
- 8- or 16-bit device support
- One with an auxiliary video extension
-
One
occupied
by
the
fixed
disk
drive
adapter
Supports 80287 math coprocessor
Same
clock
speed
as
the
system
microprocessor
“The
Model
50
does
not
support
the
FIFO
mode.
Figure
1-2.
System
Board
Devices
and
Features
1-4
Model
50
System
Overview
—
October
1990

IBM Personal System/2 50 Specifications

General

Brand	IBM
Model	Personal System/2 50
Category	Desktop
Language	English