IBM 5103 Dot matrix printer

Contents

Overview
Printing
Internals

Overview

The IBM 5103 printer is the only printer that can be attached to an IBM 5100, 5110 or 5120 computer. There are two versions of the printer: one with 80 cps and one with 120 cps.

Properties:

8 dots
132 charactes per line
10 characters per inch horizontally
6 lines per inch vertically
128 different characters
Single and fanfold paper
bidirectional printing
graphics printing possible with auxiliary programs

The print head contains 8 needles (or "dots") that are arranged in a vertical row. While printing one byte of the character, depending on the column within the character, is read from the ROS and used to drive the needle magnets. Because of the latency a needled can only be driven each second printing position (like the middle bar in the character A in the following drawing). As a character is seven dots wide there are seven bytes per character to be read from the ROS. The eighth byte is always zero to retract all needles and prepare them for the next character.

Internals

Data flow diagram of the printer adapter card

Control commands

Reset	Set	Function	Reset	Set	Function
10	90	Forms go latch	51	D1	Enable timer interrupts
	93	Not forms motor latch A and B	52		Reset timer interrupt
	97	Forms motor latch A		D4	Enable 3.3ms or 2.66ms interrupt
	9B	Forms motor latch B	54	D4	Enable print fire (5110)
	9F	Forms motor latch A and B		54	Enable 1.1ms interrupt
11	91	Enable forms interrupt (5110)	41	C1	Enable not ready interrupt
12		Reset forms interrupt (5110)	42		Reset not ready interrupt
20	A0	Print go latch	58	D8	Allow ROS addressing
21	A1	Enable print emitter interrupts		D8	Preset timer counter (5110)
22		Reset print emitter interrupt		EC	ROS address byte 0
	A3	Not print motor latches A and B		6C	ROS address byte 1
	A7	Print motor latch A		E4	ROS address byte 2
	AB	Print motor latch B		64	ROS address byte 3
	AF	Print motor latches A and B		E8	ROS address byte 4
	80	Both motors on (both go latches on)		68	ROS address byte 5
00		Both motors off (both go latches off)		E0	ROS address byte 6
				60	ROS address byte 7

Schematic diagrams

The following images have been scanned with 300 dpi from the IBM 5103 MIM (No. SY31-0414-3) and are too large to view them on screen.

Devices with EC 579623 or EC 579920
- Page 1 - 93kB
- Page 2 - 101kB
- Page 3 - 111kB
Devices without EC 579623 or EC 579920
- Page 1 - 91kB
- Page 2 - 95kB
- Page 3 - 111kB
Printer adapter card for the IBM 5100
- 80cps model - 123kB
- 120cps model - 126kB
- Identical part for both models - 127kB