Centronics 101AL Guide

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MODEL 101AL PRINTER
MAY 1H77
Cen1tronics No. 37400050 Rev. E
I:EnTROnll:S
data computer corp.
HUDSON, NEW HAMPSHIRE 03051
TELEPHONE (603) 88_3 -0111

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MODEL 101AL PRINTER
MAY 1977
REVISION F
THE INFORMATION CONTAINED HEREIN IS
PROPRIETARY AND IS NOT TO BE RELEASED
OR REPRODUCED ~ITHOUT WRITTEN PER-
MISSION OF CENTR!ONICS data computer corp.
;
!I:EnTROnll:s
ft
:data computer corporation
Hudson, New Hampshire 03051
Telephone (603) 883 - 0111

SECTION
1.1
1.2
1.3
1.4
2.1
2.2
2.3
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
5.1
5.2
6.1
6.2
6.3
6.4
6.5
TABLE OF CONTENTS
SECTION 1
INTRODUCTION
General Description. . . . . . .
Logic
Flow Diagram (Figure 1-2)
Printer Operation
..... .
Specifications . . . . . . . . .
SECTIONS 2 AND 3
INSTALLATION AND OPERATION
Site Preparation (Figure 2-1) . . . . . . . .
Shipping
Crate. . . . . . . . . . . . . .
Paper Guide and Stacker Assembly (527001001)
SECTION 4
THEORY OF OPERATION
Introduction
Basic Timing
Initializing the Printer. -.
Data Input . . . . . .
Shift Register (Buffer) .
Character Printing
Paper
Movement. . .
Special Functions
Power Supplies
Outputs From LSI
Chips.
SECTION 5
REMOVAL, REPLACEMENT AND ADJUSTMENT PROCEDURES
Introduction . . . . . .
Mechanical Assemblies
5.2.1
5.2.2
5.2.3
5.2.4
5.2.5
5.2.6
5.2.7
5.2.8
5.2.9
5.2.10
5.2.11
5.2.12
5.2.13
Cover . . . . . .
Carriage Mechanism.
Driving Mechanism
Spring Drum
Damper .....
F rallle. . . . . .
Paper
Feed Mechanism
Pin
Feed Unit . . . .
Form
Feed Mechanism
Ribbon
Feed Mechanism.
Electrical Hardware. . . .
Paper Stacker
And Guide . . . . .
Print Head and Associated Assemblies.
SECTION 6
MAINTENANCE
Electrical Adjustments
Mechanical Adjustments
Preventive Maintenance (P.M.)
Troubleshooting Guide . .
Recommended Tools . . . . .
-i-
PAGE
1-1
1-2
1-3
1-5
2-1
2-1
2-2
4-1
4-1
4-1
4-4
4-8
4-9
4-15
4-19
4-22
4-24
5-1
5-1
5-1
5-2
5-5
5-14
5-14
5-15
5-19
5-21
5-24
5-28
5-34
5-34
5-35
6-1
6-1
.. 6-2
6-4
6-6
Rev. f

Rev. F
SECTION
FIGURE
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
2-1
2-2
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
4-12
4-13
4-14
4-15
5-1
5-2
5-3
5-4
5-5
5-6
5-7
5-8
5-9
5-10
5-11
5-12
5-13
5-14
5-15
5-16
5-17
5-18
TABLE OF CONTEI\ITS
CONTINUED
SECTION 7
DRAWINGS AND LISTS OF MATEFHALS, ELECTRICAL
SECTION 8
DRAWINGS AND LISTS OF MATEHIALS, MECHANICAL
LIST OF ILLUSTRATIONS
Model 101AL Printer (Top Cover Removed)
101AL Printer Logic Flow Diagram
Printing the Letter (H)
Print Head Components . .
Paper Movement . . . . .
Left Front View of 101 A L .
Right Front View of 101AL
Rear View of 101 AL . . . . . . . . . .
Rear View (101AL Electronics Cavity Removed)
Printer Dimensions . ... . . . .
Paper Guide and Stacker Assembly
Model 101 AL Block Diagram
Prime Timing . . . . . . . .
Data I nput Timing . . . . . .
Character Timing. . . . . . .
Normal and Elongated Characters
Print Head Timing . . . . . .
Power Driver Waveform . . . .
Line Feed Ttming . . . . . .
Form Feed and Vertical Tab Timing . . . .
VFU Tape Reader Amplifier (Located in VFU)
Motor Control Location . . . . . . . . .
Motor Contro( Board Interconnection Diagram
Motor Control Timing. . . . . . . .
+5V Regulator Interconnection Diagram.
-12V Regulator Interconnection Diagram . .
Model 101 Series Drive Train . . . . . . .
Main Motor Drive and Belt Arrangements . . . .
Determining Backlash Adjustments, Shaft (HB-27). . . .
Use of Feeler Gauge for Backlash Adjustment (H B-30, 22). .
Bushing End-Play Adjustment for Preload Clutch Shaft (HB-50)
Flexible Timing Fence Mounting, Series 101 . . . . . . . .
Fence Adjustment and Optic Housing. . . . . . . . . . .
VArtical and Horizontal Alignment of Single Channel f)ptics Housing
Location of Left Reed Switch. . . . . . . . . .
Removal of Pin Feed Belt, Idler Slide and Drive Pulley . . . . . .
Adjustment for Paper Holder Gate . . . . . . . . . .. . . .
Maintaining 5/8-in. (15.9mm) Nominal Print Margin . . . . . . . . .
Two Adjustments, Gear With Stop Cam (HH-23) and Inside Cam (HH-14) .
Ribbon Feed Mechanism (Rear of Printer, Left Side)
Backlash Adjustment, Bevel Gear (H 1-43, 59)
Driving Slide Shaft A - Adjustment .
Ribbon Reversing Rod Adjustment.
Ribbon Reverse Timing . . . . . . . .
ii
PAGE
PAGE
1-2
1-2
1-3
1-3
1-4
1-6
1-6
1-7/1-8
1-7/1-8
2-1
2-2
4-2
4-3
4-5
4-11
4-12
4-13
4-14
4-16
4-17
4-18
4-20
4-20
4-21
4-23
4-23
5-5
5-7
5-11
5-12
5-13
5-16
5-17
5-18
5-H~
5-22
5-23
5-24
5-27
5-31
5-31
5-32
5-33
5-33

FIGURE
7-1
7-2
7-3
7-4
7-5
7-6
7-7
7-8
7-9
7-10
7-11
7-12
7-13
7-14
7-15
7-16
7-17
7-18
7-19
7-20
7-2'1
7-22
7-2:3
8-i
8-1
8-2
8-3
8-3A
8-4
8-5
8-6
8-7
8-'8
8-9
8-1 ()
8-12
LIST OF ILLUSTRATIONS
CONTINUED
Schematic Diagram, Logic/Power Supply +5Volts (Sheet 1)
Schematic Diagram, Logic/Power
Supply +5 Volts (Sheet 2)
Schematic Diagram, Logic/Power
Supply +5Volts (Sheet 3)
Schematic Diagram, Logic/Power Supply +5Volts (Sheet 4)
Schematic Diagram, Power Driver Board (Sheet 1)
Schematic Diagram, Power Driver Board (Sheet 2)
Schematic Diagram, Video Amplifier . . . . .
Schematic Diagram, Power Connections
101AL .
Schematic Diagram,
Motor Control. . . . . . .
Multitap Transformer 50/60 Hz.. . . . . . .
Wiring Diagram, Printer Mechanism. . . . . . . . . . .
Interconnection Diagram, Connector Board and Power
Supply . .
101 AL Connector Configuration. . . . . . . . . . . . . .
Component Board Assembly, Logic/Power Supply Board +5Volts ..
Component Board Assembly, Logic/Power Supply Board +5Volts
Component Board Assembly, Power Driver. . . . . . .
Component Board Assembly,
Video Amplifier
Component Board Assembly, Connector Card
Component Board Assembly,
Motor Control
Electronic Cavity Assembly. . . .
Harness Assembly (W1)
-. . . . .
I
nput Cable Assembly. . . . . .
Power Cable Assembly (W3)
Mechanical Subassemblies, Series
101
Cover Assembly -" A . . . .
Carriage Mechanism. . . . .
Drive Mechanism -HB (Part 1)
Drive Mechanism -HB (Part 2)
Spring Drum - He
Damper -HD ...... .
Frame -
HE . . . . . . . .
Paper Feed Mechanism . . . . .
Pin
Feed Mechanism (Left and Right) - HG .
Form Feed Mechanism - HH . . . . .
Ribbon
Feed Mechanism -HI . . . . . .
Print Head and Associated Assemblies (B) .
NOTE
Refer to the Engineering Change Notice (ECN) sheets
shipped
with the printer for changes made to the prin-
ter
which have not yet been incorporated into the draw-
ings in
this technical manual. Always keep these Engin-
eering Change
Notice sheets with the manual.
Revision
IIBvel indications at the lower right-hand corner
of a page reflect at what revision of the manual that
page was updated.
-iii/iv-
PAGE
7-2
7-3
7-4
7-5
7-6
7-7
7-8
7-9
7-10
7-11
7-12
7-13
7-14
7-15
7-16
7-19
7-21
7-23
7-25
7-27
7-29
7-31
7-33
8-2A
8-3
8-5
8-7
8-9
8-11
8-13
8-15
8-17
8-19
8-21
8-23
8-26
Rev. F

SECTION 1
INTRODUCTION
This manual describes the Model 101 AL printer, manufactured by Centronics Data Computer
Corporation.
It provides general information, detail~d theory of operation and maintenance information
enabling field service personnel to maintain the printer. For serial input or other detailed interface infor-
mation, a separate document for each interface is published for your reference.
The manual is grouped into eight sections, each with its specific purpose.
Section 1 -
INTRODUCTION, introdwces the reader to the scope and content of the
Section 2
Section 3
Section 4
Section 5
Section 5
Section 7
Section 8
manual, and provides the reader
with a general description of the printer.
-
INSTALLATION, contains unpacking and installation instructions for the printer.
- OPE RATION, describes the function of all operator controls and indicators and
how they are used.
-
THEORY OF OPERATION, contains adetailed description of each major opera-
tion performed by the printer electronics, including timing diagrams and, where
applicablH simplified
circuit diagrams, all keyed to the schematic drawings.
-
REMOVAL, REPLACEMIENT AND ADJUSTMENT PROCEDURES, includes
step-by-step removal and replacement procedures
for all major assemblies and
sub-assemblies in the printer.
-
MAl NTENANCE, includes preventive and corrective maintenance procedures and
a maintenance schedule.
-
ELECTR~CAL DRAWINGS AND LIST OF MATERIALS, contains a complete set
of schematic, wiring and component board layout diagrams and their associated list
of materials for the electrical portion of the printer.
-
MECHANICAL DRAWINGS AND PARTS LISTS, includes all printer assembly
drawings and
their associated parts lists for the mechanical portion of the printer.
At the end of the manual are several appendices which include a glossary of signal mnemonics, a standard
9 x 7, 54-character set, and parallel interface specifications.
1.1 GENERAL DESCRIPTION
The Model101AL printer (Figure 1-1) is a medium speed impact printer which uses a 9 x 7 dot matrix
for character generation. The unit prints at a rate of 155 characters per second with an average speed of 132
characters per second (including the return
time for the printing head). The printer is capable of printing 132
columns,
with paper width varying from 4 inches to '14-7/8 inches. The unit uses sprocket-fed paper and gen-
erates 5 lines to the inch vertically with 10 characters per inch, horizontally. The printer does not require spe
cial paper and can produce one original plus four copies.
The
printer is completely self-contained. A singile printed circuit board contains both the control logic
and power supplies, made possible
by the use of LSI (Large Scale Integration) circuitry.
1-1
Rev. E

Figure 1-1. MODEL 101AL PRINTER (TOP COVER REMOVED)
1.2 LOGIC FLOW DIAGRAM (Figure 1-2)
If the input device transmits serial data (100-9600 Baud) then an optional RS232 interface is re-
quired to assemble the serial data, then transfer it in parallel to the input buffer in the printer.
Paper movement is initiated by a line feed, vertical tab and form feed function. The Vertical Format
Unit (VFU) tape reader provides vertical tab and top of form spaeing control by means of a perforated
paper tape. In addition, the printer recognizes the following special control codes: bell,delete, select, de-
select and elongated character, as described in Section 1.3.3.
Once a line of printable characters is stored in the buffer, head motion is initiated by activating the
forward clutch, causing the print head to move from left to right across the paper. With the head in motion,
data is transmitted from the buffer to the character generator. From there, character write pulses are sent
to the driver circuits, which energize the print head solenoids causing the print wires to form the characters
on the paper.
Rev. E
DATA
INPUT
-
-
TIMING
VFU
OPERATOR
TAPE
BUZZER
FENCE
READER
PANEL
• • t ,
CONTROL
HEAD MOTlON_
CLUTCH/
CONTROL -
1.
PRINT COMMAND
(CR OR LAST CHAR.)
PAPER MOTION_
PAPER
2. PAPER
MOVEMENT
~
MOVEMENl"
(LF, VT, FF)
CONTROL
SOLENOID
3.
SPECIAL FUNCTIONS
(BEL~DELET~EX~
TIMING
CHAR)
1
SHIFT
-' CHJlIRACTER I
WRITE _J PRINT
1
-
REGISTER
-I
GENERATOR J PULSES" I
HEAD
BUFFER
Figure 1-2. 101AL PRINTER LOGIC FLOW DIAGRAM
1-2

1.3 PRINTER OPERATION
Basically, all printer functions can be grouped into one of the following three categories: 1)
character printing, 2) paper moveme.nt, and 3) other auxiliary functions such as printer select/de-
select, delete, etc.
1.3.1
CHARACTER PRINTING
A small aluminum carriage supports the print head assembly. During printing operation, the car-
riage travels along the
print line from left to right at a constant rate of approximately 16.25 inches per
second, and returns in
approximately 240 milliseconds.
Printing
is accomplished by selectively firing the print wires. These wires graphically construct the
characters
out of dots, as the print head moves from left to right across the print line.
Printing impulses energize the
print solenoids and drive the print wires against the ribbon, paper and
platen
to form the characters in a dot matrix pattern. When the solenoids are de-energized, the wires are
withdrawn so they are flush with the surface of the jewel. Each solenoid can fire independently up to
five times for anyone character. Figure 1-3 is an example of the dot matrix forming the letter H. All
character formations in the standard 9 x 7 dot matrix are shown in Appendix B.
PRINT
HEAD
JEWEL
Figure 1-3. PRINTING THE LETTER (H)
PRINT WIRES
A
Figure 1-4. PRINT HEAD COMPONENTS
The print head (Figure 1-4) consists of the jewal, casting and seven solenoids with attached print wires.
The
seven print solenoids and their attached print wires are arranged around the print head. The free
ends
of the print wires pass through a wire guide at the front of the print head, which properly spaces
the wires so that the correct wires passes through the correct hole in the print jewel.
Printing action
is initiated when the input buffer has been filled or a carriage return (CR) character has
been received. The print head then sweeps across the page until a CR command is decoded at the buffer out-
put or the head reaches the 132-column limit right li'mit switch. At this time, the print head returns to the left
margin and an automatic line feed is performed. As as an option, the automatic line feed can be disabled.
1.3.2 PAPER
MOVEMENT
Paper can be moved manually by rotating the platen knob (shown in Figure 1-5) or automatically by
any of three paper movement commands: line feed, vertical tab and form feed.
1-3 nev.
l: