IBM 5150 Hardware Reference Manual

INS 8250 Functional Pin Description ............... 2-129
Input Signals
................................... 2-129
Output Signals
................................. 2-132
Input/Output Signals
............................ 2-133
Programming Considerations
....................... 2-133
Asynchronous Communications Reset Functions
... 2-133
INS 8250 Accessable Registers
.................. 2-134
INS 8250 Line Control Register.
................. 2-134
INS 8250 Programmable Baud Rate Generator
.... 2-135
Line Status Register
............................ 2-137
Interrupt Identification Register
.................. 2-139
Interrupt Enable Register
........................ 2-141
Modem Control Register
........................ 2-142
Modem Status Register.
......................... 2-143
Receiver Buffer Register
......................... 2-144
Transmitter Holding Register
.................... 2-145
Selecting The Interface Format.
.................... 2-146
Asynchronous Communications Adapter Connector
Interface Specifications
.......................... 2-147
SECTION 3. ROM and SYSTEM USAGE ....... 3-1
ROM BIOS ..................................... 3-2
Use of BIOS
..................................... 3-2
Parameter Passing
................................ 3-2
Interrupt Vector Listing
............................ 3-3
Vectors With Special Meaning
..................... 3-5
Interrupt 1 CH - Timer Tick ...................... 3-5
Interrupt IDH - Video Parameters ................ 3-5
Interrupt lEH - Diskette Parameters .............. 3-5
Interrupt IFH - Graphics Character Extensions .... 3-6
Other Read/Write Memory Usage
................ 3-6
BIOS Programming Tip
........................... 3-6
BIOS Memory Map
............................... 3-7
BIOS Cassette Logic
............................. 3-8
Interrupt
15 ...................................... 3-8
Cassette Write
................................... 3-8
Cassette Read
.................................... 3-9
Data Record Architecture
.......................... 3-10
Error Recovery
................................... 3-10
vii

IBM 5150 Specifications

General

Brand	IBM
Model	5150
Category	Desktop
Language	English