Canon BJC-4400 Series User manual

QY8-13P1-000
MAY. 1998
COPYRIGHT  1998 CANON INC. CANON BJC-4400 PRINTED IN JAPAN (IMPRIME AU JAPON)
REVISION 0
SERVICE
REFERENCE MANUAL
Q30-2830-220 120V(CCSI)
Q30-2830-221 120V(CAN)
Q30-2830-222 (UNIVERSAL)
Q30-2830-230,630 220V-240V(EUR)
Q30-2830-231,631 220V-240V(GER)
Q30-2830-232,632 220V-240V(FRN)
Q30-2830-280,680 220V-240V(UK)

Application
This manual has been issued by Canon Inc. for qualified persons to learn technical theory, installation, maintenance, and repair
of products. This manual covers all localities where the products are sold. For this reason, there may be information in this
manual that does not apply to your locality.
Corrections
This manual could include technical inaccuracies or typographical errors due to improvements or changes in the products. When
changes occur in applicable products or in the content of this manual, Canon will release technical information as the need arises.
In the event of major changes in the contents of this manual over a long or short period, Canon will issue a new editions of this
manual.
The following paragraph does not apply to any countries where such provisions are inconsistent with local law.
Trademarks
The product names and company names described in this manual are the registered trademarks of the individual companies.
Copyright
This manual is copyrighted with all rights reserved. Under the copyright laws, this manual may not be copied, reproduced or
translated into another language, in whole or in part, without the written consent of Canon Inc., except in the case of internal
business use.
Copyright 1998 by Canon Inc.
CANON INC.
BJ Products Technical Support Dept
16-1, Shimonoge 3-chome, Takatsu-ku, Kawasaki-shi, Kanagawa 213, Japan
This manual was produced on an Apple MacintoshPower Mac 8500/180 personal computer and Apple
LaserWriter16/600PS-J laser beam printer; final pages were printed on Varityper5300 with 4000-J RIP. All graphics were
produced with MACROMEDIAFREEHAND5.5J.
All documents and all page layouts were created with QuarkXPress3.3J.

I.PREFACE
This manual is based on the following manuals, and only includes differences between BJC-4300 and
BJC-4400.
QY8-1352-000 BJC-4300 SERVICE MANUAL, Rev.0
II.CONTENTS
CHAPTER 1: MAJOR CHANGES
This chapter explains the main differences between BJC-4300 and BJC-4400.
CHAPTER 2: SERVICE MANUAL
This chapter explains the main differences between the SERVICE MANUAL of the BJC-4300 and
BJC-4400.
NOTE
· Page No. displayed are those of pages to be replaced for each item.

CHAPTER 1
MAJOR CHANGES

I.MAJOR CHANGES
BJC-4400 contains the following modifications compared to BJC-4300.
1.1 PRODUCT SPECIFICATIONS
1. Faster throughput speed(especially in HS mode)
2. T-shirt Transfer (TR-201) added as media type
1.2 PRINTER MECHANICAL SYSTEM
1. Countermeasures for quality improvements to the current model were incorporated
Shape changes : Carriage, paper delivery guide, platen and bottom case
Additional changes : Increased area and amount of grease application
1.3 PRINTER ELECTRICAL SYSTEM
1. To improve throughput speed, the carriage motor, the paper feed motor and the motor driver were
modified.

CHAPTER 2
SERVICE MANUAL

Part 2: Product Specifications
BJC-4400
2-1
1. PRODUCT OUTLINE
1.1 Product Outline
This full color bubble jet desktop printer not only realizes high image printing through the implementation
of the PhotoRealism concept, but also higher speed printing compared to previous models.
This printer achieves high image printing by adopting "drop modulation technology" in the color BJ
cartridge and the photo BJ cartridge.
The expanded printing environment has allowed the printer to have banner printing capabilities. The
printer can also be used as a compact color scanner when the scanner cartridge is installed in the carriage.
All the function settings are easily set by the personal computer. The operation is easily performed with the
bidirectional Centronics interface (effective only for the device ID response)
This printer uses a built-in AC adapter. This is a small and light weight personal color printer with high
performance capabilities.
AC Adapter
Parallel Interface Connector
Manual Feeding Slot
Paper Support Cut Sheet Feeder
Paper Guide
Operator Panel Front Cover
Paper Output Tray
Paper Output Tray Extension Guide
BJ Cartridge Container
Figure 2-1 Printer Exterior

Part 2: Product Specifications
2-2
1.2 Features
1. Higher speed printing
Black BJ Cartridge : 5.5 PPM (HS mode)
Color BJ Cartridge : 2.2 PPM (HS mode)
2. Compact (desk-top size)
Dimensions: 383 mm W
x231.6 mm D x203 mm H
Weight: Approx. 3.5 kg (7.7 lbs) (including color BJ cartridge)
3. Built-in AC adapter employs a high-current capable switching power supply.
4. Automatic power control (auto power on/off)
5. High quality printing of 720 x 360 dpi (in both monochrome and black when using the special printer
driver)
6. Two standard built-in printer control modes
LQ mode (EPSON LQ-2550 emulation)
BJ mode (IBM Proprinter X24E emulation)
[Canon extended mode is supported when using the canon printer driver.]
7. User replaceable BJ cartridge and adopting drop modulation technology color/ photo BJ cartridge .
Color BJ Cartridge Drop modulation technology has been adopted.
(Multi drop) It has separate ink cartridges (Bk) (Y, M, C) and the head with 136 nozzles
in a vertical line; 64 nozzles (Bk) + 24 nozzles x3 (Y, M, C).
Black BJ Cartridge Contains the black ink and the head with 128 nozzles.
Depending on each sales territory, it is not packed with the printer, but is
available separately.
Photo BJ Cartridge Drop modulation technology has been adopted.
(Multi drop) It has integrated ink cartridges with the head with 136 nozzles in a vertical
line; 64 nozzles (Bk) + 24 nozzles x3 (Y, M, C).
Black ink cartridge Black ink cartridge for the color BJ cartridge.
Color ink cartridge Tri-color (Y, M, C) ink cartridge for the color BJ cartridge.
(*Previous color and photo BJ cartridges that do not use drop modulation technology may be used,
however the printing quality will be the same as when drop modulation technology is not used.)
8. Device ID compatible to "Plug and Play"
(Responds only to the device ID/status of nibble mode)
9. Banner printing capabilities.
10. Capable of the double paper feeding with the leverless cut sheet feeder and manual feed. (It is possible
to feed paper manually even when the paper has been set on the cut sheet feeder.)
11. Photo quality printing using the Photo kit option and the photo printing special driver.
12. Cartridge container packed with the printer.
13. High quality photo image input using the option color image scanner cartridge.
BJC-4400

Part 2: Product Specifications
2-8
2. SPECIFICATIONS
2.1 Printer Specifications
1. Type
Desk-top serial color bubble jet printer
2. Paper feeding method
Auto feeding and manual feeding
3. Cut Sheet Feeder capacity
Plain paper: Maximum 10 mm (approximately 100 pages of 64g/m2paper)
Envelopes: 10 envelopes (Commercial number 10 and DL)
Transparencies: 50 sheets
BPF: 10 sheets
Glossy film/ BJ cloth: One page with the manual feeding
Scanning document: Place between the scanning holder. One page with the ASF.
4. Manual feeding slot capacity
One sheet
5. Paper weight
Automatic feed / Manual feeding slot: 64 to 105 g/m2(17 lbs to 28 lbs)
6. Printing speed
Burst
7. Printing direction
Unidirectional
(Print direction is automatically changed according to optimum printing directional control.)
8. Printing width
Maximum 8”
9. Line feed speed
90 ms/line (128/360” line)
10. Built-in printing control modes
LQ mode: Epson LQ-2550 emulation
BJ mode: IBM Proprinter X24E emulation
(Canon extended mode is supported when the Canon driver is used.)
11. Line feed pitch (n: programmable)
LQ mode: 1/6”, 1/8”, n/60”, n/72”, n/180”, n/216”, and n/360”
BJ mode: 1/6”, 1/8”, n/180”, and n/360”
BJC-4400
Color BJ Cartridge (Black printing) Black BJ Cartridge (Black printing)
HQ mode 173 cps (10 cpi) 346 cps (10 cpi)
HS mode 271 cps (10 cpi) 542 cps (10 cpi)

Part 2: Product Specifications
2-9
11. Printing characters
Typefaces: LQ&BJ mode Roman, Gothic, Courier, Prestige, Script, Draft
Pitch: LQ mode 10, 12, 15, 17, 20 cpi, and PS
BJ mode 10, 12, 17 cpi ,and PS
Character matrix: HQ mode 36 (H) x48 (V) dots
HS mode 18 out of 36 (H) x48 (V) dots
Character set: LQ mode Italic character set and Graphic character set
and International character set
BJ mode IBM character set 1, 2
and all character set
(code page 437, 850, 852 860, 863 and 865)
12. Number of columns printed
13. Bit image
Vertical: 8, 24 and 48 dots
Horizontal: 60, 120, 180, 240, 360 and 720* dpi
* In smoothing mode or when using the Canon driver.
14. Buffer
15. Interface
IEEE1284 compatible parallel interface
BJC-4400
Mode Pitch cpl *
LQ mode 10 cpi 10 cpi 80 cpl
10 cpi doublewide 5 cpi 40 cpl
10 cpi condensed 17 cpi 137 cpl
10 cpi condensed-doublewide 8.5 cpi 68 cpl
12 cpi 12 cpi 96 cpl
12 cpi doublewide 6 cpi 48 cpl
12 cpi condensed 20 cpi 160 cpl
12 cpi condensed-doublewide 10 cpi 80 cpl
15 cpi 15 cpi 120 cpl
15 cpi doublewide 7.5 cpi 60 cpl
Proportional spacing PS Varies
BJ mode 10 cpi 10 cpi 80 cpl
10 cpi doublewide 5 cpi 40 cpl
10 cpi condensed 17 cpi 137 cpl
10 cpi condensed-doublewide 8.5 cpi 68 cpl
12 cpi 12 cpi 96 cpl
12 cpi doublewide 6 cpi 48 cpl
Proportional spacing PS Varies
* cpl: characters per line
Receive buffer Download buffer
LQ mode 22 kB 32 kB
BJ mode 22 kB 0 kB

Part 2: Product Specifications
2-10
BJC-4400
16. BJ cartridge
Color BJ cartridge (Multi Drop)
Type: Color BJ cartridge with replaceable ink cartridges
Print head: 136 nozzles (vertically-lined) Bk (64 nozzles) + Y, M, C (24 nozzles x3)
Ink colors: Black, cyan, magenta, yellow
Service life:
Approximately 160 pages (in the HQ mode with 1500 character pattern) with a black cartridge
Approximately 90 pages (in the HQ mode) with a color cartridge (7.5% duty per color pattern)
Weight: Approximately 85 g (3.0 oz) (including black and color ink tanks)
Black BJ cartridge
Type: Black BJ cartridge with integrated ink
Print head: 128 nozzles (vertically-lined)
Ink color: Black
Service life: Approximately 700 pages (in the HQ mode); cartridge
Weight: Approximately 85 g (3.0 oz)
Photo BJ cartridge (Multi Drop)
Type: Color BJ cartridge with integrated ink
Print head: 136 nozzles (vertically-lined) Bk (64 nozzles) + Y, M, C (24 nozzles x3)
Ink colors: Black, cyan, magenta, yellow
Service life: Approximately 25 pages (in the Photo mode); cartridge
Weight: Approximately 74 g (2.8 oz)
17. Sensor functions
Paper out: Provided
Installation of cartridge: Provided
BJ cartridge/Scanner cartridge identification: Provided
Waste ink amount: Provided
Ink out: None
Paper width: None
18. Acoustic noise level
Approximately 45dB (A)/ HQ 48dB (A)/ HS
(Sound pressure level: According to ISO 9296)
19. Ambient conditions
20. Power source
21. Dimensions
383 mm W
✕231.6 mm D ✕203 mm H
22. Weight
Approximately 3.5 kg (7.7 lbs) (including BJ cartridge)
During operation During storage
Temperature 5°C to 35°C 0°C to 35°C
(41°F to 95°F) (32°F to 95°F)
Humidity 10% to 90%RH 5% to 95%RH
(no condensation) (no condensation)
Voltage/Frequency Power consumption Stand-by status
USA/Canada AC 120V 60 Hz
UK/Australia AC 240V 50 Hz Max. 30 W Max. 4 W
Europe AC 230V 50 Hz

2.3 Paper Specifications
2.3.1 Paper size
Letter (8.5” ✕11”)
Legal (8.5” ✕14”)
A5 (148 mm ✕210 mm)
A4 (210 mm ✕297 mm)
Commercial number 10 envelope (9.5” ✕4.1”)
European DL-size (220 mm ✕110 mm)
2.3.2 Paper type (Recommended)
Plain paper
Bubble jet paper (Canon LC-301))
Envelope (Commercial number 10 or European DL)
Transparencies (Canon transparency film CF-102)
BPF (Canon back print film BF-102)
Glossy photo paper (Canon glossy paper GP-201)
High gloss paper (Canon high gloss Film HG-101)
Fabric (Fabric sheet FS-101)
Banner (Banner paper)
T-shirt transfer (Canon T-shirt Transfer TR-201)
2.3.3 Print paper
Part 2: Product Specifications
2-12
BJC-4400
Media Thickness Lever Paper Feed Flap
Black Color/Photo Method Limit Position
Plain paper Left Center Sheet feeder 10 mm Flat
High resolution paper Center Sheet feeder 10 mm Upright
Envelopes Right Sheet feeder 10 Flat
Transparencies Center Sheet feeder 50 sheets Upright
Back print film Center Sheet feeder 10 sheets Upright
Glossy photo paper Center Sheet feeder 1 sheet Upright
Banner paper Right Sheet feeder 1 sheet Upright
Fabric sheet Right Sheet feeder 1 sheet Upright
High gloss film Center Manual feed slot 1 sheet*1 Upright
T-shirt transfer Right Sheet feeder 1 sheet Flat

Part 3: Operating Instructions
BJC-4400
3-2
1.2 Printer Dimensions
The printer’s dimensions are shown below. Allow enough space for the printer to be used with ease.
For banner printing leave a space about the size of an A4-size paper in front of the printer. Also allow
enough space at the back of the printer to set the banner paper.
· Do not place the printer in excessive heat or humidity.
· Operate the printer under the following conditions:
Ambient temperature: 5°C to 35°C
Relative humidity: 10% to 90% (no condensation)
· Do not place the printer in direct sunlight.
· Do not place the printer near a device containing a magnet or that generates a magnetic
field.
· Place the printer on a level and stable surface.
· Do not place the printer in areas subject to vibration.
· Keep the printer clean.
· When moving the printer, hold both ends.
281 mm
268 mm
304 mm
383 mm
NOTE
Figure 3-2 Printer Dimension

Part 3: Operating Instructions
BJC-4400
3-10
1.5 Paper Settings
For optimum printing, the printer has various paper settings to suit various types of paper. Set the paper
selection lever before loading the paper.
*1 Slide one sheet all the way into the manual feeding slot.
1.6 Banner Print
When printing on banner paper, lower the paper support and set the paper delivery flap to the upright
position. To avoid misfeeding, put a light crease between the first and second page and set the first page in
the sheet feeder. Place the rest of the banner paper behind the printer. Do not use the manual feeding slot
to avoid skewing.
Each top margin for banner printing is set at 0mm. However, to avoid printing on the platen, printing will
start 3mm from the initial top margin. Set an extra sheet at the end in case the bottom edge is not printed
on the last page.
Banner printing uses a large amount of ink. To avoid ink shortage, use of a new ink cartridge before
banner printing is recommended.
Media Thickness Lever Paper Feed Flap
Black Color/Photo Method Limit Position
Plain paper Left Center Sheet feeder 10 mm Flat
High resolution paper Center Sheet feeder 10 mm Upright
Envelopes Right Sheet feeder 10 envelopes Flat
Transparencies Center Sheet feeder 50 sheets Upright
Back print film Center Sheet feeder 10 sheets Upright
Glossy photo paper Center Sheet feeder 1 sheet Upright
Banner paper Right Sheet feeder 1 sheet Upright
Fabric sheet Right Sheet feeder 1 sheet Upright
High gloss film Center Manual feed slot 1 sheet*1 Upright
T-shirt Transfer Right Sheet feeder 1 sheet Flat
TABLE 3-1 QUICK REFERENCE FOR SETTING
Banner Paper
Paper Delivery Flap
Output Tray Extention Guide
Figure 3-12 Banner Print

Part 3: Operating Instructions
3-11
7 Name of the Parts and Their Functions
The different parts of the printer and their functions are shown below.
BJC-4400
Paper Support
Cut Sheet Feeder
Holds a stack of approximately 100 cut
sheets (64g/cm) for automatic feeding.
Paper Guide
Aligns the cut sheets in the cut sheet feeder
according to the paper size. A maximum
paper width of 241 mm (9.64 in.) can be set.
Autofeeds banner paper and scanning
document.
Control Panel
Front Cover
Paper Output Tray
Manual Feeding Slot
AC Adapter
Parallel Interface Connector
2
See the next page.
Open to install or remove the cartridge, set
the paper thickness lever, or remove the jams
paper.
Pulls out to receive the printed sheets.
Use for feeding media
manually.
Installed on the rear of the
printer, the AC adapter
supplies power from the power
outlet to the printer.
Depending on the location of
purchase, the power cable is
permanently attached to the
AC adapter where as in some
areas the power cable is
detachable.
Connects the printer to the
parallel port on the computer.
Supports the stack of paper loaded in the
cut sheet feeder.
Figure 3-13 Name of the Parts and Their Functions

4-1
BJC-4400
Part 4: Technical Reference
1. OVERVIEW
1.1 Printer Diagram
I/F
Logic Board
VH (+24.0VDC)
Vcc (+5VDC)
EEPROMDRAM
Control/CG ROM
Printer
Controller
MPU
Carriage Motor
Driver
J2
J4 J5 J3
J1
Paper Feed
Motor Driver
Carriage Motor
Paper Feed Motor
Carriage
· BJ Cartridge/ Scanner Cartridge
· Home Position Sensor
Figure 4-1 Printer Diagram

4. PRINTER ELECTRICAL SYSTEM
4.1 Overview
The electrical system functions are handled by the logic section or power supply.
The logic section converts the data from the interface into print signals or printer operation signals and
drives the BJ cartridge and motors while monitoring the status of the sensors.
The power supply unit consists of a built in AC adapter which provides DC output to the logic board,
motors and head etc.When DC input power from the AC adapter is being supplied, all of the hardware
components are active except for the following which are inactive: All buttons except the POWER button,
and the photo interrupter's sensor.
4-37
BJC-4400
Part 4: Technical Reference
Carriage Ribbon Cable
Carriage Motor
DRAM
POWER Switch
RESUME Switch
Printer Controller
CARTRIDGE Switch
MPU
Beeper
Paper Feed Motor
Control/CG ROM
Paper End Sensor
Pick-up Roller Sensor
AC Adapter
J3 J5
Carriage Motor Driver
Paper Feed Motor Driver
J1
J2
J4
Figure 4-27 Printer Electrical System

4.2 Logic Section
4.2.1 Logic section block diagram
Part 4: Technical Reference
4-38
BJC-4400
Figure 4-29 Printer Block Diagram
MPU
Parallel Interface
22.11MHz
Printer Controller
P60 to 63
P90 to 93
A0 to 23
AD0 to 15
A0 to 23
Carriage Motor
ERROR
POWER
Beeper
Transistor 8-Mbit
Control/CG ROM
AD0 to 15
PB0
PB1 P71
P33
A/Data Bus
Address Bus
Paper Feed Motor
BZ
RES
RES
CE
CS0
RESUME
CARTRIDGE
Driver IC
Paper End Sensor
PS1
Pickup Roller Sensor
PS2
P72
P73
A0 to 18
D0 to 15
20MHz
P41
Reset IC
Home Position Sensor
P40
Transistor
PC2 to 3
AD16 to 23
PM
PM
DRAM
4-Mbit
MA0 to 9
MD0 to 15 A0 to 9
DRAM Bus
DO 1 to 16
A0 to 15
MA0 to 9
MD0 to 15
AN0
Temp. Sensor
(TH1)
P87
POWER Switch
P42
P66
INT 0 to 3
EEPROM P35,36
PB0,PB1
PB4,PB5
BJ Cartridge
• Sub-heater
• Temperature control
heater
• Head temperature
sensor
• Rank resistor
Black BJ Cartridge
heater (128 nozzles)
Color BJ Cartridge
heater (136 nozzles)
VHC,CVDC
AN1,3
Driver IC
1 Kbit
PE4 to 7
MCH0
ID0,1
HRES
HCLOCK
HDATA
HLATCH
BENB1 to 3
HENB0 to 3
ODDENB
EVENENB Scanner Cartridge
(Option)
• Scanner controller
• CCD
• LEDs (R,G,B)
HVH
H VDD
SCLOCK
SDATA
SLATCH
COM 0 to 3
C.CHK
C.CHA
P94
P95
Vcc (+5VDC)
VH (+24.0VDC)
Logic Board
J2
Cartridge
Control
Bi-directional
Interface Control
Control Buttons
Indicators
Indicator Control Switch Detection
J4
Mechanism
Control
Carriage Motor
Temp.
Sensor
(TH1)
Pick-up
Roller
Sensor
Paper
End
Sensor J3
Purge Unit
Paper Feed Roller
MECHANISM SECTION
ELECTRICAL SECTION
Sheet
Feeder
J1
Paper Feed Motor
AC Adapter
J5
AC Inlet
BJ Cartridge
Home Position Sensor Scanner Cartridge (Option)
LEDs
(R,G,B) CCD
Scanner
Controller
Carriage
Figure 4-28 Logic Board Block Diagram

4.2.2 Logic section components
1) MPU (IC2)
The MPU contains a 16-bit CPU, 1K-bit RAM, 24-bit address bus port, 16-bit data bus port, stepping
motor controller, interrupter controller, A-D converter, I/O ports, and other components.
Built-in CPU
The 16-bit CPU operates in synchronization with a 20 MHz external clock input.
Address bus
The 24-bit address bus port is connected to an 8 M-bit control/CG ROM and printer controller. The
controller/CG ROM synchronizes with the read signals output by the MPU and the 20 MHz clock
signal. The printer controller then selects the chip.
Data bus
Like the address bus, the 16-bit data bus port is connected to the 8 M-bit control/CG ROM and printer
controller.
Stepping motor controller
The stepping motor controller outputs double 1-2 phase exciter drive signals to both the carriage motor
driver and paper feed motor driver.
The stepping motor controller can switch the the 4-step peak current value of both motor driver.
Interrupt controller
For external interruption, the MPU has ports P80, 81, 84, 85, and 87 to receive the POWER button
on/off switching, data reception, initial interrupt request, receive buffer-full warning, and other signals.
The MPU executes interrupt processing for the respective signals.
A-D converter
The following analog signals are detected after they pass through the built-in A-D converter:
AN0: The printer's internal temperature is detected by the thermistor on the logic board.
AN1: The head temperature is detected by the head temperature sensor in the BJ cartridge.
AN3: The head rank is detected by the rank resistor in the BJ cartridge.
I/O port
The setting status determined by the head ID, paper end sensor, home position sensor, and pick-up
roller sensor are input through the input ports. The buzzer, BJ cartridge detection, head-driving voltage
control, and other signals are output from the output ports.
4-39
BJC-4400
Part 4: Technical Reference

2) Printer controller (IC3)
The printer controller contains the interface controller, print head controller, buffer controller, DRAM
controller, EEPROM controller, I/O ports, etc. It operates in synchronization with an external 22.11
MHz external clock input.
Interface controller
The interface controller receives from the computer, 8-bit parallel data which is synchronized with the
data strobe pulse (STROBE) through the BUSY/ACKNLG handshake. It also controls other interface
signals.
The data received through the interface is stored in the DRAM's receive buffer and analyzed by the
MPU.
When the printer initialization signal INIT is input through the interface to the printer controller, the
printer controller outputs a BUSY signal. Also, after INT1 is output to the MPU and print data in the
print buffer is printed, the printer is initialized.
DRAM controller
The DRAM controller is a DRAM-specific bus separated from the MPU bus. It controls the 4 M bit
DRAM's 10-bit address/16-bit data bus and also executes read/write control, RAS/CAS control, and
refresh control.
Buffer controller
The buffer controller automatically writes the received data to the receive buffer on the DRAM,
manages the receive buffer's remaining capacity, automatically reads the print buffer, and clears the data
after it is read.
Print head controller
The print head controller converts the print data read from the DRAM's print buffer from parallel to
serial and sends it to the print head. At the same time, the printed dots are counted for the variable
control of the Heat-enable (H ENB) signal pulse width.
The head-driving signals consist of the block enable signals (B ENB 1, 2, 3), odd/even enable signals
(OddENB/EvenENB), and heat enable signals (H ENB 0, 1, 2, 3). The block enable signals and
odd/even enable signals specify the block for time-shared drive. The heat enable signals control the
eject heater's conduction time.
I/O port
The I/O ports sense the RESUME and CARTRIDGE buttons' input status. The output ports control
the lighting of the POWER and ERROR indicators.
Part 4: Technical Reference
4-40
BJC-4400