Epson Stylus Photo 720 User manual

EPSONStylusPhoto72
0
EPSONStylusPhotoEX
3
EPSON STYLUS PHOTO 720 / STYLUS PHOTO EX3
Color Inkjet Printer
SEIJ00001

SERVICE MANUAL
SERVICE MANUALSERVICE MANUAL
SERVICE MANUAL

Notice:
n All rights reserved. No part of this manual may be reproduced, stored in a retrieval system, or transmitted in any form or by any means,
electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SEIKO EPSON CORPORATION.
n The contents of this manual are subject to change without notice.
n All efforts have been made to ensure the accuracy of the contents of this manual. However, should any errors be detected, SEIKO EPSON
would greatly appreciate being informed of them.
n The above not withstanding SEIKO EPSON CORPORATION can assume no responsibility for any errors in this manual or the consequences
thereof.
EPSON is a registered trademark of SEIKO EPSON CORPORATION.
General Notice: Other product names used herein are for identification purpose only and may be trademarks or registered trademarks of their
respective owners. EPSON disclaims any and all rights in those marks.
Copyright © 2000 SEIKO EPSON CORPORATION. Printed in Japan.

PRECAUTIONS
Precautionary notations throughout the text are categorized relative to 1)Personal injury and 2) damage to equipment.
DANGER Signals a precaution which, if ignored, could result in serious or fatal personal injury. Great caution should be exercised in
performing procedures preceded by DANGER Headings.
WARNING Signals a precaution which, if ignored, could result in damage to equipment.
The precautionary measures itemized below should always be observed when performing repair/maintenance procedures.
DANGER
1. ALWAYS DISCONNECT THE PRODUCT FROM THE POWER SOURCE AND PERIPHERAL DEVICES PERFORMING ANY
MAINTENANCE OR REPAIR PROCEDURES.
2. NO WORK SHOULD BE PERFORMED ON THE UNIT BY PERSONS UNFAMILIAR WITH BASIC SAFETY MEASURES AS DICTATED
FOR ALL ELECTRONICS TECHNICIANS IN THEIR LINE OF WORK.
3. WHEN PERFORMING TESTING AS DICTATED WITHIN THIS MANUAL, DO NOT CONNECT THE UNIT TO A POWER SOURCE UNTIL
INSTRUCTED TO DO SO. WHEN THE POWER SUPPLY CABLE MUST BE CONNECTED, USE EXTREME CAUTION IN WORKING ON
POWER SUPPLY AND OTHER ELECTRONIC COMPONENTS.
WARNING
1. REPAIRS ON EPSON PRODUCT SHOULD BE PERFORMED ONLY BY AN EPSON CERTIFIED REPAIR TECHNICIAN.
2. MAKE CERTAIN THAT THE SOURCE VOLTAGES IS THE SAME AS THE RATED VOLTAGE, LISTED ON THE SERIAL NUMBER/
RATING PLATE. IF THE EPSON PRODUCT HAS A PRIMARY AC RATING DIFFERENT FROM AVAILABLE POWER SOURCE, DO NOT
CONNECT IT TO THE POWER SOURCE.
3. ALWAYS VERIFY THAT THE EPSON PRODUCT HAS BEEN DISCONNECTED FROM THE POWER SOURCE BEFORE REMOVING OR
REPLACING PRINTED CIRCUIT BOARDS AND/OR INDIVIDUAL CHIPS.
4. IN ORDER TO PROTECT SENSITIVE MICROPROCESSORS AND CIRCUITRY, USE STATIC DISCHARGE EQUIPMENT, SUCH AS
ANTI-STATIC WRIST STRAPS, WHEN ACCESSING INTERNAL COMPONENTS.
5. REPLACE MALFUNCTIONING COMPONENTS ONLY WITH THOSE COMPONENTS BY THE MANUFACTURE; INTRODUCTION OF
SECOND-SOURCE ICs OR OTHER NONAPPROVED COMPONENTS MAY DAMAGE THE PRODUCT AND VOID ANY APPLICABLE
EPSON WARRANTY.

About This Manual
This manual describes basic functions, theory of electrical and
mechanical operations, maintenance and repair procedures of EPSON
Stylus Photo 720 / Stylus Photo EX3. The instructions and procedures
included herein are intended for the experienced repair technicians, and
attention should be given to the precautions on the preceding page.
Contents
This manual consists of six chapters and Appendix.
CHAPTER 1.PRODUCT DESCRIPTIONS
Provides a general overview and specifications of the
product.
CHAPTER 2.OPERATING PRINCIPLES
Describes the theory of electrical and mechanical
operations of the product.
CHAPTER 3.TROUBLESHOOTING
Provides the step-by-step procedures for the
troubleshooting.
CHAPTER 4.DISASSEMBLY AND ASSEMBLY
Describes the step-by-step procedures for
disassembling and assembling the product.
CHAPTER 5.ADJUSTMENTS
Provides Epson-approved methods for adjustment.
CHAPTER 6.MAINTENANCE
Provides preventive maintenance procedures and the
lists of Epson-approved lubricants and adhesives
required for servicing the product.
APPENDIXProvides the following additional information for
reference:
• Connector pin assignments
• Electric circuit boards components layout
• Exploded diagram
• Electrical circuit boards schematics
Symbols Used in This Manual
Various symbols are used throughout this manual either to provide
additional information on a specific topic or to warn of possible danger
present during a procedure or an action. Be aware of all symbols when
they are used, and always read WARNING, CAUTION or NOTE
messages.
Indicates an operating or maintenance procedure, practice
or condition that, if not strictly observed, could result in injury
or loss of life.
Indicates an operating or maintenance procedure, practice,
or condition that, if not strictly observed, could result in
damage to, or destruction of, equipment.
May indicate an operating or maintenance procedure,
practice or condition that is necessary to accomplish a task
efficiently. It may also provide additional information that is
related to a specific subject, or comment on the results
achieved through a previous action.
W ARNING
CAUTION
CHECK
POINT

Revision Status
Revision Issued Date Description
Rev. A April 6, 2000 First Release

EPSON Stylus Photo 720 / EPSON Stylus Photo EX
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Contents
Product Description
Overview ....................................................................................................... 9
Features ................................................................................................... 9
Basic Specification .................................................................................... 10
Printing Specification .............................................................................. 10
Paper Feed specification ........................................................................ 11
Input Data Buffer .................................................................................... 11
Electric Specification .............................................................................. 11
Environmental Conditions ...................................................................... 12
Reliability ................................................................................................ 12
Safety Approvals .................................................................................... 12
Acoustic Noise ........................................................................................ 12
CE Marking ............................................................................................. 12
Interface Specification .............................................................................. 13
IEEE-1284 Parallel I/F (Forward Channel) ............................................. 13
IEEE-1284 Parallel I/F (Reverse Channel) ............................................. 13
USB (Universal Serious Bus) ................................................................. 16
Miscellanea ............................................................................................ 16
Preventing Hosts from Data Transfer Time-out .................................. 16
Interface Selection .............................................................................. 16
IEEE 1284.4 protocol ......................................................................... 17
Control Specification ................................................................................ 18
Control Panel .......................................................................................... 18
Control Switches .................................................................................... 18
Code Page Selection/ Parallel I/F IEEE1284.4 Setting ...................... 19
Special Setting Mode ......................................................................... 20
LED Indications ...................................................................................... 20
Initialization ............................................................................................. 21
Errors ...................................................................................................... 21
Paper ........................................................................................................... 22
Paper handling ....................................................................................... 22
Paper Specification ................................................................................ 22
Printable Area ........................................................................................ 24
Ink Cartridge ........................................................................................... 26
Physical Specification .............................................................................. 27
Consumables and Options ....................................................................... 28
Operating Principles
Overview .................................................................................................... 30
Printer Mechanism ................................................................................. 30
Printhead ................................................................................................ 32
Printing Process ................................................................................. 33
Printing Method .................................................................................. 34
Carriage Mechanism .............................................................................. 35
Platen Gap (PG) Adjustment Mechanism .......................................... 35
Paper Feeding Mechanism .................................................................... 36
Paper Loading Mechanism (ASF Unit) ................................................... 37
Ink System Mechanism .......................................................................... 39
Pump Unit and CR Lock Mechanism ................................................. 39
Capping Mechanism .............................................................................. 40
Ink Sequence ......................................................................................... 41
Electrical Circuit Operating Principles .................................................... 42
C301PSB/PSE Board ............................................................................. 42
C301MAIN Board ................................................................................... 44
Main elements .................................................................................... 45
Printhead Driver Circuit ...................................................................... 45
PF Motor (PF/ PUMP/ ASF Motor) Driver Circuit ............................... 47
CR Motor Driver Circuit ...................................................................... 48
Reset Circuit ....................................................................................... 48
EEPROM Control Circuit .................................................................... 49
Sensor Circuit ..................................................................................... 50

EPSON Stylus Photo 720 / EPSON Stylus Photo EX
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7
Troubleshooting
Overview ..................................................................................................... 52
Unit Level Troubleshooting ...................................................................... 54
Printer does not operate at power on ..................................................... 54
Error is detected ..................................................................................... 55
Failure occurs during printing ................................................................. 55
Printer does not feed paper correctly ..................................................... 56
Control panel operation is abnormal ...................................................... 56
Unit Repair (Power Supply Board) ........................................................... 57
Unit Repair (Control Board) ...................................................................... 58
Unit Repair (Printer Mechanism) .............................................................. 60
Disassembly and Assembly
Overview ..................................................................................................... 65
Precautions ............................................................................................ 65
Tools ....................................................................................................... 65
Work Completion Check ......................................................................... 66
Disassembly ............................................................................................... 67
Housing Removal ................................................................................... 68
Circuit Board Assembly Removal ........................................................... 69
Control Panel Removal .......................................................................... 71
Ink Absorber Tray Assembly (Waste Ink Pad) Removal ........................ 72
Printer Mechanism Disassembly ............................................................ 73
Printhead Removal ............................................................................. 73
Pump Assembly / Cap Assembly Removal ........................................ 75
CR Motor Assembly Removal ............................................................ 77
PF Motor Assembly Removal ............................................................. 78
ASF Assembly Removal ..................................................................... 80
ASF LD Roller Assembly Removal ..................................................... 82
LD Roller Assembly Disassembly ....................................................... 87
CR Assembly Removal ...................................................................... 88
PE Sensor Assembly Removal .......................................................... 90
PF Roller Assembly Removal ............................................................. 91
CR HP Sensor Removal ..................................................................... 93
Adjustment
Overview .................................................................................................... 95
Required Adjustment .............................................................................. 95
Adjustment ................................................................................................. 96
PG Adjustment ....................................................................................... 96
Adjustment by Adjustment Program ....................................................... 98
Adjustment Program .............................................................................. 98
Adjustment Program Installation Procedure ........................................... 98
Adjustment Program Initial Setting Screen ............................................ 99
Market Destination Check .................................................................... 100
Head Voltage ID Input .......................................................................... 101
Head Angular Adjustment .................................................................... 103
Bi-Directional Adjustment ..................................................................... 106
USB ID Check/Input ............................................................................. 109
Head Cleaning ..................................................................................... 110
Initial Ink Charge .................................................................................. 111
Protection Counter Check/Clear .......................................................... 111
Print A4 Pattern .................................................................................... 113
Maintenance
Overview .................................................................................................. 115
Cleaning ............................................................................................... 115
Service Maintenance ............................................................................ 116
Lubrication ............................................................................................ 117
Appendix
Connector Summary ............................................................................... 122
Major Component Unit ......................................................................... 122
EEPROM Address Map ....................................................................... 125
Component Layout .................................................................................. 129
Exploded Diagram ................................................................................... 131
Parts List .................................................................................................. 139
Electric Circuit ......................................................................................... 149

CHAPTER
1
PRODUCT DESCRIPTION

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1.1 Overview
Stylus Photo 720 and Stylus Photo EX3 is developed from Stylus Photo 700 and Stylus
Photo EX and allows a high resolution photographic high quality print enabled by
variable dot.
1.1.1 Features
Major features of this printer are as follows;
o High color print quality
n 1440x720 (HxV) dpi printing
n Photo-MACH technology (6 color printing. CMYKLmLc)
n Traditional and New Microweave
o Built-inASF(AutoSheetFeeder)
n Holds 100 cut-sheets (64 g/m
2
)
n Holds 10 envelopes
n Holds 30 transparency films
o Built-in 2 I/F
n Bi-directional parallel I/F (IEEE-1284 level 1 device)
n USB (Universal Serial Bus)
o Windows / Macintosh exclusive
Figure 1-1. External View
Stylus Photo EX3
Stylus Photo 720

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1.2 Basic Specification
1.2.1 Printing Specification
PRINTING METHOD
o On demand ink jet
NOZZLE CONFIGURATION
o Black: 32 nozzle
o Color: 32 nozzle x 5 colors
(Cyan, Magenta, Yellow, Light Cyan, Light Magenta)
Figure 1-2. Nozzle Configuration (Seen from the Back of the Head)
PRINTING DIRECTION
o Bi-direction with logic seeking
PRINTING SPEED AND PRINTABLE COLUMNS
o Character mode: Refer to the table below.
NOTE: These figures are not described in the user’s guide.
** This value is the speed of normal-dot printing.
o Raster graphics mode: Refer to the table below.
CONTROL CODE
o ESC/P Raster command
o EPSON Remote command
4 / 360"
Black Magenta
Light
Cyan
Cyan Light
Magenta Yellow
#1
#32
nozzle
Table 1-1. Printing Speed (Character Mode)
Character Pitch Printable Columns LQ speed
Stylus Photo 720 10 CPI (Pica) 80 200 CPS**
Stylus Photo EX3 10 CPI (Pica) 114 200 CPS**
Table 1-2. Printing Speed (Raster Graphics Mode)
Horizontal
Resolution
Printable
Area
Available
Dot CR Speed
Stylus Photo 720
180 dpi 8.26 inch 1488 508mm/s (20 IPS)
360 dpi 8.26 inch 2976 508mm/s (20 IPS)
720 dpi 8.26 inch 5952 508mm/s (20 IPS)
Stylus Photo EX3
180 dpi 11.46 inch 2062 508mm/s (20 IPS)
360 dpi 11.46 inch 4125 508mm/s (20 IPS)
720 dpi 11.46 inch 8250 508mm/s (20 IPS)

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CHARACTER TABLES
o 2 international character sets
n PC437 (US, Standard Europe)
n PC850 (Multilingual)
TYPEFACE
o Bitmap LQ font
n EPSON Courier 10 CPI
1.2.2 Paper Feed specification
o Feeding Method: Friction feed with ASF
o Paper path: Cut-sheet ASF (Top entry Front out)
o Feed speed: 10.16mm feed: 110ms
Continuous feed: 114.3mm/s
1.2.3 Input Data Buffer
o Buffer: 256 Kbytes
1.2.4 Electric Specification
o 120V version
n Rated voltage: AC 100V
n Input voltage range: AC 99 -132V
n Rated frequency range: 50 - 60Hz
n Input frequency range: 49.5-60.5 Hz
n Rated current: 0.4A (Max. TBD)
n Power consumption: Approx.18W (ISO10561 Letter pattern)
Approx. 2.5W in standby mode
Energy Star compliant
n Insulation Resistance: 10 M ohms min.
(between AC line and chassis, DC 500V)
n Dielectric: AC 1000 V rms. 1 minute or
AC 1200 V rms. 1 second
(between AC line and chassis)
o 220-240V version
n Rated voltage: AC 220 - 240V
n Input voltage range: AC 198 - 264V
n Rated frequency range: 50 - 60Hz
n Input frequency range: 49.5-60.5 Hz
n Rated current: 0.2A (Max. TBD)
n Power consumption: Approx.18W (ISO10561 Letter pattern)
Approx. 2.5W in standby mode
Energy Star compliant
n Insulation Resistance: 10 M ohms min.
(between AC line and chassis, DC 500V)
n Dielectric: AC 1500 V rms. 1 minute
(between AC line and chassis)

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1.2.5 Environmental Conditions
o Temperature
Operating: 10 to 35°C*3
Non-operating: -20 to 40°C*1
1monthat40°C, 120 hours at 60°C
o Humidity
Operating: 20 to 80% RH*2,*3
Non-operating: 5 to 85% RH*1,*2
o Resistance to shock
Operating: 1G, within 1ms
Non-operating: 2G, within 2ms*1
o Resistance to vibration
Operating: 0.15G
Non-operating: 0.50G*1
NOTE: *1: with shipment container.
*2: without condensation.
*3: The environmental condition should be within the range shown in the
figure below.
Figure 1-3. Environmental Condition
1.2.6 Reliability
o Total print volume: 10,000 pages (A4, Letter)
o Print Head Life: 3 billion dots / nozzle
Or 5 years at the normal temperature
(Whichever comes first.)
1.2.7 Safety Approvals
o 120V version:
n Safety Standards: UL1950
CSA22.2 No.950
n EMI: FCC part15 subpart B class B
CSA C108.8 class B
o 220 - 240V version:
n Safety Standards: EN 60950 (VDE)
n EMI: EN 55022 (CISPR Pub. 22) class B
AS/NZS 3548 class B
1.2.8 Acoustic Noise
o Level: Approx. 47dB (A) (According to ISO7779)
1.2.9 CE Marking
220-240V version
o Low Voltage Directive 73/23/EEC: EN60950
o EMC Directive 89/336/EEC: EN55022 class B
EN61000-3-2
EN61000-3-3
EN50082-1
IEC801-2
IEC801-3
IEC801-4
(”C)
(%)
80
55
20
10 27 35
tmphumid

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1.3 Interface Specification
This printer has IEEE-1284 parallel interface and USB interface as standard.
1.3.1 IEEE-1284 Parallel I/F (Forward Channel)
Forward channel is the mode to transfer the ordinary printing command to the printer
side from the PC side.
NOTE: I/F cable is recommended to be in minimum length.
The connector pin assignment is described below. For these signals described in the
table, use the twist pair wire and connect the return side to the signal GND.
1.3.2 IEEE-1284 Parallel I/F (Reverse Channel)
Reverse channel is used to transfer the information data from the printer side to the PC
side.
Table 1-3. Parallel I/F Specification (F-Channel)
Item Specification
Transmission mode 8bit parallel
Synchronization By STROBE pulse supplied from the external
Handshaking By BUSY and ACKNLG signal
Signal Level TTL level (IEEE-1284-Level 1 device)
Adaptable connector 36 pin 57-30360 (amphenol) or equivalent
Table 1-4. Connector Pin Assignment and Signals (F-Channel)
Pin No. Return
GND Pin
Signal
Name From Function Description
1 19 -STROBE PC
The strobe pulse for the printer to read data.
Pulse width requires min. 0.5µs (500ns).
High at normal condition. Receives data after
shifting Low.
2-9 20-27 Data0-7 PC The DATA 1 through DATA8 signals
represent data bits 1-8, respectively.
10 28 -ACKNLG Printer
A low signal indicates the printer can accept
data. Pulse width is 0.5 (default) or can be set
at 2µs.
11 29 BUSY Printer
A high signal indicates that the printer cannot
receive data. The signal becomes high under
the condition below;
-Receiving data.
-Error.
-Other I/F receiving data.
12 28 PE Printer A high signal indicates paper-out error.
13 28 SLCT Printer Always at high level. Pulled up to +5V via
1.0KΩ resistor.
14 30 -AFXT PC Not used.
31 30 -INIT PC The printer is initialized by the width of min.
50µs Low pulse input.
32 29 -ERROR PC A low signal indicates printer error condition.
36 30 -SLIN -Not used.
18 - Logic H - Always at high level. Pulled up to +5V via
3.9KΩresistor.
35 -+5V -Always at high level. Pulled up to +5V via
1.0KΩresistor.
17 - Chassis - Printer chassis GND.
16, 33
19-30 -GND -Twist pair return GND.
15, 34 - NC - Not used.
Table 1-4. Connector Pin Assignment and Signals (F-Channel)
Pin No. Return
GND Pin
Signal
Name From Function Description

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o Device ID
n When IEEE-1284.4 protocol is effective:
[00H] [5AH]
MFG: EPSON;
CMD: ESCPL2, BDC, D4;
MDL: Stylus[SP]Photo[SP]720;
*1
CLS: PRINTER;
DES: EPSON[SP]Stylus[SP]Photo[SP]720;
*1
n When IEEE1284.4 protocol is NOT effective:
[00H] [57H]
MFG: EPSON;
CMD: ESCPL2, BDC;
MDL: Stylus[SP]Photo[SP]720;
*1
CLS: PRINTER;
DES: EPSON[SP]Stylus[SP]Photo[SP]720;
*1
Note: *1 For Stylus Photo EX3, MDL: Stylus[SP]Photo[SP]EX3;
DES: EPSON[SP]Stylus[SP]Photo[SP]EX3, respectively.
The connector pin assignment is described in the table below. For these signals
described in the table, use the twist pair wire and connect the return side to the signal
GND.
Table 1-5. Parallel I/F Specification (R-Channel)
Item Specification
Transmission mode IEEE-1284 nibble mode
Synchronization Comply with the IEEE-1284 specification
Handshaking Comply with the IEEE-1284 specification
Logic Level TTL level (IEEE-1284-Level 1 device)
Data trans. timing Comply with the IEEE-1284 specification
Extensibility request data The printer responds affirmatively when the extensibility request
values are 00H or 04H;
00H: Request Nibble Mode Reverse Channel Transfer.
04H: Request Device ID;
Return Data Using Nibble Mode Reverse Channel Transfer
Table 1-6. Connector Pin Assignment and Signals (F-Channel)
Pin No. Return
GND Pin Signal Name From Function Description
1 19 HostClk PC Host clock signal.
2-9 20-27 Data1-8 PC The DATA 1 through DATA8 signals
represent data bits 1-8 respectively.
10 28 PtrClk Printer Printer clock signal.
11 29 PtrBusy/
DataBit-3,7 Printer Printer busy signal and reverse channel transfer data bit 3 or 7.
12 28 AckDataReq/
DataBit-2,6 Printer Acknowledge data request signal and reverse channel transfer data bit 2 or 6.
13 28 Xflag/DataBit-
1,5 Printer X-flag signal and reverse channel transfer data bit 1 or 5.

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Following lists “Notes” when using the parallel interface.
o “Return GND pin” in the table means twist pair return and is connected to the
signal GND level.
For each signal, use the twist pair wire and connect the return side.
Also, these cables are shielded wires and it is effective means to connect to each
chassis GND in the center machine and printer for electrostatic noise.
o Conditions for interface are all based on TTL level. Rise and fall time should be
within 0.2µs.
o Refer to the timing chart for transmission timing of each signals.
o Do not perform data transmission ignoring -ACK or BUSY signals. (Perform the
data transmission after confirming that either -ACK or BUSY signal is Low)
o It is possible to perform the printing test including interface circuit without using
external equipment when 8-bit data signal (2-9 pin) is set to appropriate character
code (against GND, Open=”1”, Short=”0”) and connect then forcefully to -ACK
and -STRB. However, to perform this, “I/F selection” of EEPROM must be set to
“Auto”. Also, IEEE-1284.4 packet mode must be set Off.
The figure below shows the timing chart of the parallel interface.
Figure 1-4. Timing Chart
On the above timing chart, Tact ratedperiodisshownbelow.
14 30 HostBusy PC Host busy signal.
31 30 -INIT PC Not used.
32 29 -DataAvail/
DataBit-0,4 Printer Data available signal and reverse channel transfer data bit 0 or 4.
36 30 1284-Active PC 1284 active signal.
18 - Logic H Printer Pulled up to +5V via 3.9K ohm resistor.
35 -+5V Printer Pulled up to +5V via 3.3 K ohm resistor.
17 - Chassis - Printer chassis GND.
16, 33
19-30 -GND -Twist pair return GND.
15, 34 - NC - Not used.
Table 1-6. Connector Pin Assignment and Signals (F-Channel)
Pin No. Return
GND Pin Signal Name From Function Description
Table 1-7. tact Rated Period
Parallel I/F Mode Tact Rated Period
High speed (default) 0.5 µs
Normal speed 2µs
Data byte nData byte n+1DATA
/STROBE
BUSY
/ACKNLG
t hold
t setup
t ready
t stb
t busy
t reply
t ack
t nbusy
t next
timechart

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1.3.3 USB (Universal Serious Bus)
Following shows specification.
o Standard:
n Universal Serial Bus Specifications Revision 1.0
n Universal Serial Bus Device Class Definition for Printing Devices version 1.1
o Bit rate: 12Mbyte (Full Speed Device)
o Data encoding: NRZI
o Adaptable connector: USB Series B
o Recommended cable length: max. 2 meters
Figure 1-5. USB Interface Port
1.3.4 Miscellanea
1.3.4.1 Preventing Hosts from Data Transfer Time-out
Generally, hosts abandon data transfer to peripherals when a peripheral is in busy state
for dozens of seconds continuously. To prevent hosts from acting this kind of time-out,
when the open space of input buffer becomes 1024 byte, the printer receives data per
certain period of time (1 second) and avoid BUSY state continues for a long time. The
printer will be in busy state continuously when the input buffer finally gets full. This
operation is not performed while communicating by IEEE1284.4 protocol.
1.3.4.2 Interface Selection
IEEE-1284 parallel interface and USB interface is switched by auto select function.
The following explains the conditional shift of the I/F auto select function and the
operations when specific interface is set.
AUTOMATIC SELECTION
In this automatic interface selection mode, the printer is initialized to the idle state
scanning which interface receives data when it is powered on. Then the interface that
receives data first is selected. When the host stops data transfer and the printer is in the
stand-by state for the seconds, the printer is returned to the idle state. As long as the
host sends data or the printer interface is in the busy state, the selected interface is let as
is.
INTERFACE STATE AND INTERFACE SELECTION
o When the parallel interface is not selected, the interface became to the busy state.
When the printer is initialized or returned to the idle state, the parallel interface
became to the ready state. Caution that the interrupt signal such as the -INIT signal
on the parallel interface is not effective while the inter face is not selected.
Table 1-8. Connector Pin Assignment and Signals
Pin.
No Signal Name I/Out Function Description
1VCC --
Cable power. Maximum power consumption
is 2mA.
2-Data I/O Data
3 +Data I/O Data. Pull up to +3.3V via 1.5K ohm resistor.
4Ground -- Cable ground.
Pin #1Pin #2
Pin #3 Pin #4
usb

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1.3.4.3 IEEE 1284.4 protocol
The packet protocol described by IEEE1284.4 standard always a device to carry on
multiple exchanges or conversations which contain data and/or control information
with another device at the same time across a single point-to-point link. The protocol is
not, however, a device control language. It does provide basic transport-level flow
control and multiplexing services. The multiplexed logical channels are independent of
each other and blocking of one has no effect on the others. The protocol operate over
IEEE1284.
o Auto
An initial state is compatible interface and starts IEEE1284.4 communication
when the magic strings (1284.4 synchronous commands) are received.
o On
An initial state is IEEE 1284.4 communication and data that received it by the time
it is able to take synchronization by magic string (1284.4 synchronous commands)
is discarded.
o Off
An initial state is compatible interface and never starts IEEE1284.4
communication even if the magic strings (1284.4 synchronous commands) are
received.
For parallel I/F, regardless of the factory default setting, after initial ink charge
operation, the setting of the EEPROM must be set to “AUTO”. The change in this
setting will be effective when the power is back on after the initial ink charge
operation.

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1.4 Control Specification
1.4.1 Control Panel
The control panel is at the front right of the printer and has 2 non-lock type push
switches and 1 lock type switch and 4 LEDs. The appearance of the control panel
differs between Stylus Photo 720 and Stylus Photo EX3, but the number of buttons and
LEDs is the same. So, this section explains names of the buttons using the Stylus Photo
720 control panel.
Figure 1-6. Control Panel
1.4.2 Control Switches
Since this printer does not have so many switches, each button has several functions.
The tables below show their functions and how to enter those functions for each button.
Power Button
Load/ Eject Button
Ink Maintenance Button
Paper Check LED
Black Ink End LED
Power LED
Color Ink End LED
Table 1-9. Panel Functions in Normal State
Button Function
Load/Eject
(Less than 2 seconds)
Load or eject paper
When the print head is at the ink replacement position, it returns to
the home position.
Load/ Eject
(for 3 seconds)
Start the ink cartridge replacement sequence.
Ink maintenance
(for 3 seconds)
Start cleaning the print head.
In the condition of “Ink Low”, “Ink End” or “No Ink Cartridge”,
start the ink cartridge replacement sequence.
Ink maintenance
(Less than 2 seconds)
When the print head is at the ink replacement position, it returns to
the home position.

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NOTE: Turning the power on = to turn on the printer power while specified
button is pressed down.
*1: Printer performs the following according to the value of 1BH in EEPROM.
1.4.2.1 Code Page Selection/ Parallel I/F IEEE1284.4 Setting
On this setting mode, you can select code page table (PC437 or PC850) and parallel I/F
IEEE1284.4 mode (ON, AUTO, OFF).
o Code Page Selection
You can select the code table PC437 or PC850 by the following panel operation.
1. Turn on the power while pressing the maintenance button.
2. Paper check LED starts blinking.
3. When you see the paper check LED starts blinking, release maintenance button.
4. After 2 seconds, the code page setting will be indicated by maintenance LED. See the
table below.
NOTE: You can check current code page by status print.
Table 1-10. Panel Function with Turning the Power On *Note
Button Function
Load/Eject Start status-printing.*1
Print “Firmware version”→ “CPU Mask version”→ “Waste
ink counter”→ “Code page setting”→ “Nozzle check pattern”.
Ink maintenance Code page.selection/ Parallel I/F IEEE 1284.4 setting (See
Section 1.4.2.1)
Load/Eject
+
Ink maintenance
Start special setting mode.
(See Table 1-13)
Table 1-11. EEPROM 1BH Data and Function W
Bit 7, Bit 6 Action
00 Print firmware version, ink counter, selected code page and nozzle
check pattern.
11
01 Start hex-dump printing.
10 Start self-test printing.
Table 1-12. Code Page Setting
Code page before this
function is performed.
Code page after this
function is performed. LED Indication
PC437 PC850 Ink END (Color) ON
PC850 PC437 Ink END (Black) ON

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1.4.2.2 Special Setting Mode
You can go to the special setting mode by the following operations.
1. Turn on the power while pressing the Load/ Eject button and ink maintenance button.
2. Paper check LED starts blinking. (3 seconds)
3. While the paper check LED is blinking (3 seconds), press the appropriate button. See
Table 1-13.
NOTE: Hold the button pressed for 10 seconds.
1.4.3 LED Indications
See the table below for more detailed LED indications. Since LED indicates the
various errors and current printer operations, LED indications enable to find out the
proper repair operation.
NOTE: *1 For error condition, refer to “Fatal Error” under the “Errors” on
page 21.
*2 EEPROM clear does not mean to clear all address in
EEPROM. (See “Special Settings Mode” on page 20)
*3 -- in the table above means no change.
n When maintenance error (protection counter over flow) is
happened, if you clear the error by this operation, be sure to
replace the waste ink absorber.
n Whenever you replaced the waste ink counter (even when ink
maintenance error has not occurred), be sure to perform the
counter reset by this operation.
Table 1-13. Special Settings Mode
Buttons Function
Load/Eject Initialize EEPROM and reset timer IC.
This operation will reset the following items:
• Interface selection (04H)
• CL time (68/ 69H)
• Power OFF time (6C/ 6DH)
Cleaning
(Pressed for 10 seconds)
Reset the ink overflow counter.
This operation will reset the following items:
• Ink counter A0 (5C/ 5DH)
• Ink counter A80 (5E/ 5FH)
Table 1-14. Printer Status displayed on the control panel
Printer Status
Indicators
Power Paper
Check
Ink End
(Black)
Ink end
(Color) Priority
Power on condition On --*3 -- -- 9
Ink sequence Blink -- -- -- 6
Ink cartridge exchange mode Blink -- -- -- 5
Data processing Blink -- -- -- 8
Paper check*1 -- On -- -- 4
Paper jam*1 -- Blink Off Off 3
No ink cartridge or Ink end
(black)*1 -- -- On -- 7
No ink cartridge or Ink end
(color)*1 -- -- -- On 7
Ink level low (black) -- -- Blink -- 7
Ink level low (color) -- -- -- Blink 7
EEPROM and Timer IC reset*2 --
On
(for 1
second)
On
(for 1
second)
On
(for 1
second)
--
Maintenance Request Blink Blink Blink Blink 2
Fatal Error*1 Blink Blink On On 1