Epson LQ-1050 Technical Manual

Terminal printer
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EPSON
EPSON TERMINAL PRINTER
L Q - 8 5 0 / 1 0 5 O

TECHNICAL MANUAL

Y45499901 o-z
. . . . . . .

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Summary of Contents for Epson LQ-1050

  • Page 1: Technical Manual

    EPSON EPSON TERMINAL PRINTER L Q - 8 5 0 / 1 0 5 O TECHNICAL MANUAL Y45499901 o-z ..
  • Page 2 THE POWER SUPPLY CABLE MUST BE CONNECTED, USE EXTREME CAUTION IN WORKING ON POWER SUPPLY AND OTHER ELECTRONIC COMPONENTS. WARNING REPAIRS ON EPSON PRODUCT SHOULD BE PERFORMED ONLY BY AN EPSON CERTIFIED REPAIR TECHNICIAN. MAKE CERTAIN THAT THE SOURCE VOLTAGE IS THE SAME AS THE RATED VOLTAGE, LISTED ON THE SERIAL NUMBER/RATING PLATE.
  • Page 3 Includes a step-by-step guide for product disassembly, assembly, and adjustment. Chapter 5 - Provides Epson-approved techniques for troubleshooting. Chapter 6 - Describes preventive maintenance techniques and lists lubricants and adhesives required to service the equipment. The contents of this manual are subject to change without notice.
  • Page 4 REVISION TABLE CHANGE DOCUMENT REVISION DATE ISSUED Aug. 31, 1987 1st issue...
  • Page 5 REV.-A TABLE OF CONTENTS GENERAL DESCRIPTION CHAPTER 1. CHAPTER 2. OPERATING PRINCIPLES OPTIONAL EQUIPMENTS CHAPTER 3. DISASSEMBLY, ASSEMBLY, AND ADJUSTMENT CHAPTER 4. TROUBLESHOOTING CHAPTER 5. MAINTENANCE CHAPTER 6. APPENDIX vi -...
  • Page 6: Table Of Contents

    REV.-A CHAPTER 1 GENERAL DESCRI PTION FEATURES ....................
  • Page 7 REV.-A LIST OF FIGURES LQ-850/l 050 ........1- 1 Fig.
  • Page 8 REV.-A LIST OF TABLES Optional Units...........o..mmm..mmo.mmm""".."".. 1- 2 Table 1-1. Table 1-2. Optional Interface Boards ........... . 1- 2 Line Feed Speeds .
  • Page 9: Features

    Auto backing of fanfold paper and autoloadin9 of cut sheet paper Auto ejecting of cut sheet paper and autoloadin9 of fanfold paper Printing of fanfold paper without removal of the cut sheet feeder (option) Optional interface for the EPSON 8100 series Optional low-priced, cut sheet feeder which cont~ins...
  • Page 10: Table 1-1. Optional Units

    Table 1-1. Optional Units LQ-850 LO-1 050 Name Tractor unit #73 11 Tractor unit #731 2 # 7 3 3 9 Cut sheet feeder (single-bin) # 7 3 4 0 Cut sheet feeder (single-bin) # 7 7 5 3 Ribbon cartridge # 7 7 5 4 Ribbon cartridge # 7 4 0 0...
  • Page 11: Specifications

    REV.-A 1.2 SPECIFICATIONS The LQ-850/ 1050 communicates with a wide variety of host computers, with aid of the optional Identity Module. However, this section describes the specifications for the printer without the Identity Module option. Specifications not affected by firmware (hardware specifications) are the same whether or not the Identity Module is installed.
  • Page 12: Table 1-3. Line Feed Speeds

    REV.-A Do not more than 1/6 inches. perform reverse feeding for Because accuracy of paper feed cannot be assured, do not perform reverse feeding after the paper end has been detected. b) When using pull tractor feed: Remove the paper tension unit and mount the pull tractor unit. Use the paper path when a single sheet is inserted.
  • Page 13: Fig. 1-3. Cut Sheet Paper Printable Area

    REV.-A Table 1-5. Fanfold Paper Specified Conditions LQ-1 050 LQ-850 1 0 . O ” ) 406 (4.0 16.0”) 101 - 254 (4.0 - Width [ m m ] 4 (1 original + 3 ) at normal temperature Copies [sheet] 3 (1 original + 2 ) at all temperature range Plain paper Quality...
  • Page 14: Fig. 1-4. Fanfold Paper Printable Area

    REV.-A Fanfold paper See Figure 1-4. 4 - 1O*1(1 6)”, 101 - 254 (406) mm P r i n t a b l e a r e a J * 2 Printable area 0.35”, 9 mm 0 - - m o r e - - - - - - - - - - - - - - - - - - —...
  • Page 15: Table 1-6. Lever Adjustment

    REV.-A NOTES: 1. Printing of labels is only available at normal temperature. 2. Labels must be fanfold. 3. Labels with pressure-sensitive paper must be jointed by pasting along the dots or lines, and the total thickness must be less than equal to 0.3 mm (O.
  • Page 16: Table 1-8. Dimensions And Weight

    REV.-A Dimensions See Table 1-8 (Details are shown in Figures A-45 and 46.) W e i g h t See Table 1-8. Table 1-8. Dimensions and Weight Weight [Kg] Width [mm] [mm] Depth [mm] Height 4 3 0 3 6 0 LQ-850 6 0 5 1 4 2...
  • Page 17: Firmware Specifications

    REV.-A Safety Approvals UL478 (U.S.A. version) Safety standards CSA22.2#l 54 VDE0806 (TUV) (Europe an version) Radio Frequency (RFI) FCC class B (U.S.A. version) Interference VDE871 (self-certification) (Europe version) 1.2.2 Firmware Specifications ESC/P-83 Control Code Printing Direction Text Bidirectional with logic seeking Bit-image Unidirectional 8 bits...
  • Page 18 REV.-A Table 1-11. Printirm Mode Printable Double Printing Speed Empha- Charac- Print Con- [CPS] Columns Width ter Pitch Pitch densed sized LQ-1 050 [cPI] Draft LQ-850 17.1 2 6 4 @ 7 < Ignored — Max. Max. 1 1 6 160 Min.
  • Page 19: Fig. 1-6. Character Matrix

    REV.-A See Figure 1-6 and Table 1-12. C h a r a c t e r M a t r i x (Superscript Character) 24 are not used when superscript (Normal Character) Pin Nos. 17 to printing. — Ascender Area Ascender Area (15P itch ) - 8 P 1--1...
  • Page 20: Table 1-11. Printing Mode

    REV.-A Character Size See Table 1-12. Table 1-12. Character Matrix and Character Size Character Size Unit Printing Mode Face Matrix V. (mm) 1.9 X 3.2 9 X 23 DRAFT, 10 pitch 1.9 X 3.2 DRAFT, 12 pitch 9 X 23 9 X 16 1.0 ~ 2.3 DRAFT, 15 pitch...
  • Page 21: Interface Overflew

    REV.-A 1.3 INTERFACE OVERVIEW The LQ-850/l 050 has both 8-bit parallel interface and RS-232C serial interface as standard. They can be selected by DIP switches 2-3 and 2-4 respectively. (This detail of DIP switch settings, refer to Table 1-1 7.) 1.3.1 8-bit Parallel Interface Specifications 8-bit pallarel Data Transmission Mode...
  • Page 22: Rs-232C Serial Interface Specifica~Ions

    REV.-A 1.3.2 RS-232C Serial Interface Specifications RS-232C serial Data Transmission Mode Asynchronous Synchronization Handshaking By DTR (REV) signal or X-ON\OFF protocol Refer to Table 1-13 and Figure 1-9. Table 1-13. Serial Interface Handshaking DTR Signal X-ON/OFF protocol Description MARK X-OFF (13H) When the number of bytes remaining in the input buffer reaches 256 or less, the signal level goes to MARK, or a X-OFF code is sent out to the host computer.
  • Page 23: Fig. 1-11. Serial Interface Connector

    REV.-A t’+ - - - - - - ---S ~ ( -v) [ +V] - - - - - - - - - - - - - - - - - - - - - -o~j-z~3~q-g-6~j: [ -v] Stop Bit Data Bit Pari~Y Start...
  • Page 24: Dip Switch And Jumper Settings

    REV.-A DIP Switch and Jumper Settings The DIP switches that users can set are SW1 and SW2. These switches are positioned at the rear of the printer, and have the functions as shown in Tables 1-14 through 1-18, (note that the status of the DIP switches are read only when the printer power on or an INIT signal is input.) Table 1-14.
  • Page 25: Table 1-16. Dip Switch 2 Settings

    Table 1-16. DIP Switch 2 Settings Function DIP SW. 12“ 11 “ Page length I 1“ Valid Invalid skip-over perforation See Table 1-17. Interface selection Baud rate selection See Table 1-18. Tear off mode Valid Invalid Valid- Invalid Auto LF —...
  • Page 26: Table 1-19. Jumper Setting

    REV.-A Fiugre 1-12 shows the factory settings for DIP switches SW-1 and SW-2. Country U. S. A., Southeast Asia, Middle and Near East Germany, Northern Europe U. K., Australia F r a n c e , Itary, Spain White areas indicate the setting. 1 and 2 Factory Settings Fig.
  • Page 27: Self-Test Operation

    REV.-A 1.5 SELF-TEST OPERATION The LQ-850/l 050 printer has the following self-test operation. The control ROM version No. and the DIP switch settings also printout when the self-test is performed. Table 1-20 lists the self-test operating instructions and Figure 1-13 shows the self-test printing. Table 1-20.
  • Page 28: Hexadecimal Dump Function

    REV.-A 1.6 HEXADECIMAL DUMP FUNCTION In hexadecimal dump mode, the printer prints out the data it receive? in hexadecimal format. The printer prints a column of 16 hexadecimal values, folIowed by a column containing the 16 corresponding ASCII characters. If there is no corresponding printable character for a value (e.g., a control code, such as a carriage return or line feed), a period (.
  • Page 29: Printer Initialization

    REV.-A 1.7 PRINTER INITIALIZATION There are two initialization methods: hardware initialization and software initialization. 1.7.1 Hardware Initialization This type of initialization occurs when printer power is turned on or when the printer receives the INIT signal from the host via the 8-bit parallel interface. When printer is initialized in this way, it performs the following actions: Initializes printer mechanism Clears downloaded character set...
  • Page 30: Buzzer Operation And Error Conditions

    REV.-A 1.8 BUZZER OPERATION AND ERROR CONDITIONS This section describes the buzzer operation and error conditions of the printer. 1.8.1 Buzzer Operation The buzzer ring as follows: . When a BEL code is sent to the printer, the buzzer sounds for 0.5 seconds .
  • Page 31: Main Components

    REV.-A 1.9 MAIN COMPONENTS The LQ-850/ 1050 printer includes the following major subassemblies: Model-53 10/5360 printer mechanism MONMA board (main board) MONPL board (control panel) (power supply board, 120V and 220/240V versions) MONPS/MONPSE board Figure 1-15 shows the LQ-850/l 050 component locations. 1 .—, LQ-1 050 LQ-850...
  • Page 32: Paper Leading And Paper Ejection

    REV.-A 1.9.1.1 Paper Loading and Paper Ejection The paper release lever has a disengage capability for the optional pull tractor unit’s drive mechanism. Therefore, these printers provide some improved paper handling functions that can be performed by using a combination of the paper release lever and LOAD/EJECT switch on the control panel. Single Sheet Loading and Ejection load a sheet of paper, position the paper release lever back, place the page along the paper guide, and press the LOAD/EJECT switch.
  • Page 33: Monma Board (Main Board)

    REV.-A 1.9.2 MONMA Board (Main Board) Figure 1-17 shows the MONMA board, which contains a KPD78 10HG CPU to control the operation of the printer. Driver circuits for the motors, sensors, and printhead are also included on this board. Other main ICS on the MONMA board are: Universal IC M546 10P (5A) .
  • Page 34: Monps/Monpse Board

    REV.-A 1.9.3 MONPS/MONPSE Board (Power Supply Circuit Board) The power supply circuit board is located on one of two boards, the MONPS for 120 V AC operation and the MONPSE for 220/240 V operation. The basic construction of the two boards is the same: each board contains a power switch, fuses, line filter circuit, and switching regulator circuit.
  • Page 35: Control Panel

    REV.-A 1.9.4 Control Panel In the control panel, there are four square switches, three rectangular switches, and fifteen LEDs, as shown in Figure 1-19. The functions of the switches and indicators are given immediately below the illustration. — , — P O W E R 0 P O W E R 0 REAOY R E A D Y...
  • Page 36 REV.-A LOAD/EJECT Switch Pressing this switch loads or ejects the paper (If a page is inserted into the cut sheet feeder, it is loaded; if a page is already loaded, it is ejected). Details of the paper loading and ejection process are described in Section 1.9.1.1.
  • Page 37: Housing

    REV.-A 1.9.5 Housing lower cases and accommodates the printer mechanism, control The housing consists of the upper and circuit board, and power circuit. The optional cartridges (i.e., font and identity modules) can be mounted easily without removing the upper case. Figure 1-20 shows the LQ-850/ 1050 housings. LQ-850 -.-,OF-.
  • Page 39: Operating Principles

    REV.-A CHAPTER 2 OPERATING PRINCIPLES OVERVIEW ....................2- 1 2.1.1 Connector Summary .
  • Page 40 REV.-A 2.3.2.2 RC-232C Serial interface..........2-32 2.3.3 Control Panel Interface Circuit .
  • Page 41 REV.-A Frioction Feeding Method ............2 - 9 Fig.
  • Page 42 REV.-A Fig. 2-44. +35V DC Line Voltage Monitoring Circuit ......2-43 Fig. 2-45. +35V DC Line Voltage Compensation Sequence ... 2-43 Fig.
  • Page 43: Overview

    REV.-A 2.1 OVERVIEW This chapter describes the signals at the various connectors that connect the primary components of the LQ-850/l 050, including the model-53 10/5360 printer mechanism, MONPS/MONPSE power This chapter also describes the operation supply board, MONMA control board, and the control panel. of the printer’s electric circuitry and printer mechanism.
  • Page 44 REV.-A Table 2-1. Boards Connector Summary Reference Board Connector Des&iption Pins To or From Table l/F (parallel) A-1 2 Host computer MONMA CN 1 A-1 3 Option l/F board Host l/F (RS-232C) A - 1 4 A-1 5 Not used Japan only A-1 6 Font module...
  • Page 45: Printer Mechanism Operation

    REV.-A Printer Mechanism Operation 2.1.2 The Model-53 10/5360 is a serial printer mechanism equipped with a 24-pin impact dot printhead. Two new features have been added for more efficient paper handling: automatic paper loading/ejecting, and top margin fine adjustment (tear-off mode). The printer mechanism is divided into three parts: 1 ) the printing mechanism;...
  • Page 46: Printing Mechanism

    REV.-A 2.1.2.1 Printing Mechanism The printing mechanism includes the printhead, inked ribbon, and platen. Figure 2-3 shows the printing mechanism and Table 2-2 lists the printhead specifications. The printhead has 24 dot wires which are arrayed in two 12 wire lines. Each dot wire is connected to its own drive coil. The basic printing operations are as follows: The drive signals, transferred from the control circuit to the printhead drive circuit, are converted into printhead drive voltages which energize the head driving coils for the dot wires.
  • Page 47: Carriage Mechanism

    REV.-A 2.1.2.2 Carriage Mechanism Carriage mechanism Figure 2-4 shows the carriage mechanism. The printhead is mounted on the carriage, and the entire unit is supported by the two carriage The carriage is fixed to the timing belt on one side guide shafts.
  • Page 48 REV.-A Ribbon Feed Mechanism The ribbon feed mechanism consists of the ribbon feed mechanism and ribbon carriage. Figure 2-5 shows the ribbon feed mechanism. Ribbon Feed Rolk & R i b b o n Ptess.re ~ Roller Breaking Belt Driven Pulley Planet Gear @ “ane’G?ar@.!A+i2i5% Ribbon Driving Gear...
  • Page 49: Paper Feed Mechanism

    REV.-A 2.1.2.3 Paper Feed Mechanism The paper feed mechanism feeds the paper after the printing mechanism and the carriage mechanism finish printing one line. The paper feed motor is driven to rotate the platen tractor via the paper feed gears. The paper feed mechanism includes two sensor mechanisms: A paper end sensor to detect the presence/absence of the paper, and a friction/tractor sensor to detect the paper feeding mode (push tractor feed or friction feed).
  • Page 50 REV.-A Push Tractor Feeding Method (Figure 2-6) Paper feeding is performed by driving the paper feed motor with the paper release lever set forward to load fan-fold paper into the tractor unit. A paper tension unit is installed at the exit of the case to prevent irregular paper feeding and slackening.
  • Page 51 REV.-A Friction Feeding Method (Figure 2-7) The paper is loaded from the upper paper entrance with the paper release lever set backward. The paper is held against the platen by the paper feed roller and is fed due to friction with the platen and paper unit is used to prevent paper feed feed roller.
  • Page 52: Power Supply Circuit Operation

    REV.-A 2.2 POWER SUPPLY CIRCUIT OPERATION (MONPS/MONPSE board) The DC voltages required to operate the mechanisms and control circuits are supplied from the supply board in this unit. There are two kinds of power supply boards, the MONPS board for 100 V or 120 V operation and the MONPSE board for 220 V or 240 V operation.
  • Page 53 REV.-A of the power supply circuit. External noise on the AC line is Figure 2-8 shows a block diagram first attenuated by the input filter circuit. Then the AC voltage is converted to DC by the full-wave rectifier, and is smoothed by the smoothing circuit. surge current that flows when the power is turned on.
  • Page 54: Input Filter Circuit

    REV.-A 2.2.2 Input Filter Circuit Figure 2-9 shows Input filter circuit. The filter circuit attenuates external noise and inhibits noise generated in the printer from going out over the AC line. The coils-and capacitors employed in this filter are able to handle fluctuations of the AC input line. Frame ground (F. G.) is connected between C4 and C5, which handle leakage current from the frame to the AC line.
  • Page 55: Main Switching Circuit

    REV.-A SURGE CURRENT$ ! ‘ INPUT VOLTAGE POWER ON Fig. 2-11. Surge Current The voltage across C6 increases after the power is applied, and the current is accordingly stabilized. Until the voltage across C6 becomes stable, the surge current is limited by a resistor in series with capacitor C6.
  • Page 56 REV.-A > ‘0 y - - - - - w Fig. 2-12. Main Switching Circuit 2-14...
  • Page 57: Surge Absorber

    REV.-A I (A) ( A ) ‘C”’Q:L of Q 1 ~035p( ‘T12 . I 4 1 0 3 5 1 0 - AVERAGE ton +toff~ — Fig. 2-14. RCC System Switching Operation Fig. 2-13. Waveforms at Primary and Secondary Sides of T1 L..—.
  • Page 58: Line Output Voltage Limiting

    REV.-A 2.2.4.3 +35 V Line Output Voltage Limiting The back electromotive described in 2.2.4.1 causes diode D20 on the secondary side of transformer T1 to conduct, which supplies power. Consequently, the amount of energy stored by the transformer during a unit~l~riod of time becomes equal to the power output. That is: “...
  • Page 59: Over Voltage Protection Circuit

    REV.-A 2.2.4.4 Over Voltage Protection Circuit As described in 2.2.4.3, the power supply circuit of this unit not only uses the output voltage stabilizing circuit to stabilize the output voltage (Vo) and provide feedback to the switching circuit, but it also contains an over voltage protection circuit to protect against malfunctions of the constant voltage generation circuit.
  • Page 60: Vdc Switching Regulator Circuit

    REV.-A 2.2.5 +5 VDC Switching Regulator Circuit Figure 2-17 shows the +5 VDC switching regulator. This circuit employs a hybrid type switching regulator IC STR20005 (IC20) which consists of a voltage reg~lator circuit along with coil L20 and capacitor C25 at the external output section. +35V S T R 2 0 0 0 5...
  • Page 61: Soft Start

    REV.-A ColJector Fig. 2-18. CMP Input and Output Voltage Comparison 2.2.5.3 Soft Start When power is supplied capacitor C 1, connected between the CMP side and GND, increases negative the Trl output at time constant R3 X C2 so that the on-time of Trl gradually becomes longer (Refer to Wgure 2-1 9.).
  • Page 62: F 12 Vdc Half-Wave Rectifier-Smoothing Circuit

    REV.-A 2.2.6 +12 VDC Half-Wave Rectifier-Smoothing Circuit The power from this circuit is mainly supplied to the RS-232C Interface on the optional interface board. Both the + 12 V and – 12 V lines have their own half-wave rectifier circuits. The smoothing circuits consist of capacitors C23 and C24, and include dummy resistors R27 and R28 which control the rise of voltage when the * 12 V lines have no load, as well as current limiting resistors R25 and R28.
  • Page 63: Control Circuit (Monma) Board Operation

    REV.-A 2.3 CONTROL CIRCUIT (MONMA) BOARD OPERATION MHz as the This printer employs an 8-bit one-chip CPU (wPD78 10HG) with a clock frequency of 14.75 employs an E05A01 LA gate array ( 10C) containing a memory 1/0 main control device. It also management circuit so as to extend the memory and 1/0 areas and simplify the CpU support circuitry.
  • Page 64: Reset Circuit

    REV.-A 2.3.1 Reset Circuit Figure 2-22 shows the reset circuit. After being input to gate array EO5A1OAA (MMU: 10C), the RESET signal resets the gate array and is then sent out to the other devices. Hardware reset is performed when: 1.
  • Page 65: Power On/Off

    REV.-A 2.3.1.2 Power ON/OFF When the power is switched on and Vx rises, voltage is applied to the integration circuit (composed of R88, C26, D48). The voltage at C26 increases according to Vx ( 1 – e ~) and when VTHLD VTHLD reaches Vp the output is switched from low to high (Schmitt trigger), and the reset circuit in the MMU sets the ROUT signal high (TR 1 ).
  • Page 66: Init Signal Input From Cn1 Or Cn2

    REV.-A 2.3.1.3 INIT Signal Input from CN1 or CN2 When the I NIT signal is input from outside (it should be low for 50 IA or more), it reduces the voltage at the CPU and MLT terminals via the integration circuit (R89, C26, and D48), the M546 10P (5A), and R89.
  • Page 67: Font/Identity Cartridge Installation

    REV.-A 2.3.1.4 Font/Identity Cartridge Installation and Removal The font and identity cartridges should not be installed or removed while the power is on. If this is done, the ROUT signal must be set low to prevent a main board circuit malfunction. After reset, the CPU starts execution from address OOOOH and sends a RD signal to the external memory devices.
  • Page 68 REV.-A 2.3.1 .5” Static RAM (8A) Battery Backup Circuit The memory static RAM (8A) employs a lithium battery (3.00 to 3.35 VDC) for backup, to maintain parameters and data when the power is turned off. Figure 2-26 shows the static RAM (8A) battery backup circuit.
  • Page 69: Interface

    REV.-A 2.3.2 Interface This printer has both 8-bit parallel interface and RS-232C serial interface. 2.3.2.1 8-Bit Parallel Interface Operating Principle Figure 2-27 shows the 8-bit parallel interface data transmission timing. Data is transferred between a host computer and the printer using the following sequence: BUSY ACKNLG DATA...
  • Page 70 Table 2-11. M5461OP Terminal Function Function Direction Pin No. Name + Host BUSY signal BUSY DIN8 + Host 8-bit parallel data DIN 1 + Host STROBE pulse P s w + CPU Output timing of the BUSY signal O: Positive edge of STROBE 1: Negative edge of STROBE —...
  • Page 71 REV.-A is shown The 8-bit parallel interface circuit in Figure 2-28. signal and a data exchange is External data on DIN 1-8 is input at the falling edge of the STROBE the external device. Derformed by sending the ACKNLG and BUSY si9nals fro the ‘c to r–...
  • Page 72 Set detault values. PA6--H:. . . fixed PC4--H . . . t IXed 8 - b i t data i s Inwt. s e t Inltlal v a l u e s . PBCl--H- PB2-”1+- PB3--ti- S T R O B E Pulse Is sent. d a t a I s l a t c h e d .B-blt a n d B U S Y S19nal I...
  • Page 73 READ DATA I N I T I A L I Z E EBUSY From Doul- 8 To CPU — HOST BUSY HOST DIN 1-8 VALID DATA Fig. 2-30. Interface Signal Timing Table 2-12. Relationship 8-Bit Parallel l/F Signals HOST READY/ERROR BUSY PRINTER acknowledge:...
  • Page 74: Rc-232C Serial Interface

    REV.-A 2.3.2.2 RC-232C Serial Interface Operating Principle The two handshaking methods are as follows: status flug . . . DTR (REV) signal The DTR signal is set to SPACE (+V) when the printer can accept data and is set to MARK (–V) when the printer is in an error state or when the vacant area of the input buffer reaches 256 byte or less.
  • Page 75 REV.-A Circuit Description Figure 2-33 shows the RS-232C serial interface circuit. Data transmitted from the host computer is converted from EIA to TTL voltage levels by the RS-232C line driver 75189 (9 B). The converted data is sent to CPU via buffer (6 B).
  • Page 76 set Inlt!al values. EBUSY--L (DTR-SPACE) send X-ON (llH). serla~ d a t a a r e S e n t o n RXD. 1 Ine data buffer vacant area reach EBUSY--H- (DTR=MARK). send X - O F F (13H). I I ne data buffer a r e a VdCt3nt r&3Ch...
  • Page 77: Control Panel Interface Circuit

    REV.-A 2.3.3 Control Panel Interface Circuit Figure 2-36 shows the main board control panel circuit. The seven switches, 15 LEDs, and one buzzer The firmware periodically reads the state of the switches. The are installed on the control panel. conditions at which the switch states are read are listed in Table 2-13. If the firmware detects a value different from the previous one, the value is reloaded.
  • Page 78 REV.-A ‘s .— - - - — f ! ? ) < — — “. :)” — Fig. 2-36. Relationship Between MONMA Board and MONPL Board 2-36...
  • Page 79: Cpu Address Mapping

    REV.-A DATA IN LOAD 3.46M INDICATES A NEW INDICATES AN OLD VALUE STAT E VALUE —t Fig. 2-37. MSM5837 Data Transfer Timing - - - DATA IN — DI I D12 ~ D 10 –08 — — J RESET 12- BIT L A T C H E S W I T H R E S E T LOAD 01 I...
  • Page 80 Fig. 2-39. CPU.Gate Arrays”Memories Block 2-38...
  • Page 82: Status Monitoring Circuits

    REV.-A 2.3.5 Status Monitoring Circuits The state of each sensor and switch associated with the printer mechanism is detected by the A/D converter (ports ANO-7) of the CPU. The detected value (analog data) input to each port is converted to 8-bit digital data and is compared with a reference value by the firmware. The detected signals are shown in Table 2-14.
  • Page 83: Reference Voltage Generation Circuit

    REV.-A 2.3.5.1 Reference Voltage Generation Circuit Figure 2-41 shows the generation circuit for reference voltage VDC) used in the A/D converter VAREF (4.75 in the CPU. This circuit employs a programmable shunt regulator TL43 1 (CY 1 ) for the reference voltage supply.
  • Page 84: Printhead Temperature Monitoring Circuit

    REV.-A 2.3.5.2 Printhead Temperature Monitoring Circuit Figure 2-42 is the printhead temperature monitoring circuit. This circuit detects the printhead temperature using a thermistor included the printhead. R 8 0 CN 15 AR EF TEMP I * ~ AN O & :C30 ~AVss TEMP2...
  • Page 85: Dc Line Voltage Monitoring Circuit

    REV.-A Table 2-15 shows the relationship between head temperature at limit values and voltages at ANO of the CPU. Table 2-15. Relationship Limit Value and Voltage Voltage at ANO [V] Temperature [“C] 0.82 Upper Limit 1.01 Lower Limit 2.3.5.3 +35V DC Line Voltage Monitoring Circuit As shown in Figure 2-44, this circuit detects voltage fluctuation in the +35V DC power supply line.
  • Page 86: Dip Switch Read Circuit

    REV.-A Table 2-16. Relationship Between +35V Line and AN1 +35V Line [V] AN1 [V] —-––––. Normal 31.7 Lower limit 2.3.5.4 DIP Switch Read Circuit DIP switch settings are read using analog ports AN2 through 7 after the power is applied or the INIT input initializes the CPU.
  • Page 87 FiEV.-A DIP switches SW 1-1 through 1-8 and SW 2-1 through 2-8 are read by selecting them using the three bank signals BANK 0,1, and 2 of the E05A1 OAA gate array ( 10C). Table 2-17 lists the BANK signals and analog ports.
  • Page 88: Carriage And Paper Feed Motor Control Circuit

    REV.-A 2.3.6 Carriage and Paper Feed Motors Control Circuit This printer employs an E05A09BA gate array (MCU: 2A) to control the two stepper motors (the carriage motor and paper feed motor). This gate array can independently control the stepper motors so that the CPU load is reduced.
  • Page 89: Gate Array E05A09Ba (2A)

    REV.-A 2.3.6.1 Gate Array E05A09BA (2A) This gate array contains two phase switching pulse generation circuits for 4-phase stepping motors, so that two motors can be controlled separately. The timing of the phase switching, for normal rotation, reverse rotation, or stop, and the phase switching method are controlled by control signals from the CPU.
  • Page 90: Home Position Seek Operation

    REV.-A 2.3.7 Carriage Motor Control Circuit The carriage motor control system in this printer employs an open-loop control system. 2.3.7.1 Home Position Seek Operation The function which moves the carriage to the home position after CPU inputs RESET signal is called home position seek.
  • Page 91 REV.-A HP Signal ‘hasee ~ CR Motor Phase C Phase D –- Detects HP Signal Reads and sets the phase change point in the CPU. Fig. 2-50. Home Position Seek Phase States 2-50...
  • Page 92: Logic Seeking

    Fig. 2-51. logic Seeking Operation a) Upon receive in print data “EPSON” for a line from the host computer, the printing is performed in an action of @ to @ with the carriage and printhead moving to position Q. b) The CPU, receiving the next data from the host computer, analyzes it and determines the acceleration start position of the carriage.
  • Page 93: Carriage Meter Excitation System

    REV.-A 2.3.7.3 Carriage Motor Excitation System The carriage motor is controlled by the carriage motor constant current drive circuit. The phases of the carriage motor are controlled by AO l-DO 1 of the E05A09BA (2A). Two drive systems, 2-2 phase and 1-2 phase excitation, are used.
  • Page 94: Carriage Movement Area And Speed Control

    REV.-A 2.3.7.4 Carriage Movement Area and Speed Control The carriage movement area is shown in Figure 2-53. The area is roughly divided into three parts: 1) speeds for the acceleration area, 2) printing area, and 3) deceleration area. There are six constant carriage movement, as shown in Table 2-20.
  • Page 95 REV.-A High Speed Skip Area , I Accel - Decel- / lerotj~n (~je&Os) erofionl 32m - Constant Constant speed Speed Printing Character Space (20Hx7 ) or more Fig. 2-54. High Speed Skip Deceleration Speed Control or 2, the carriage motor is decelerated for 24 pulses in the case of the 2-2 phase When the speed is 1 excitation system.
  • Page 96 REV.-A 2.3.7.5 Carriage Motor Drive Circuit This printer has STK6722H (1A) which is a unipolar stepper motor driver IC used to drive the carriage motor, using a constant current chopping method. Reference Voltage Generation Circuit Figure 2-55 shows the reference voltage generation circuit, and Table 2-21 shows the relationship between ports of E05A09BA (2A) and the reference voltage.
  • Page 97 REV.-A General Operation Figure 2-56 shows the carriage motor drive circuit block diagram. The carriage motor has four coils A, B, C, and D, and each coil is driven by the corresponding phase driver A to D. These phase drivers are switched directory by the output pulses from ports AO 1 to DO 1 of the MCU (2A).
  • Page 98 REV.-A Detailed Operation (Figure 2-57.) When the + 5V supply voltage is applied to the STK6722H (H-IC: 1 A), the triangular waveform circuit in the H-IC starts oscillation and outputs the reference signal (approx. 24 KHz) for chopper control. IC2 (point Q) is high (input at the side >...
  • Page 99: Paper Feed Motor Control Circuit

    REV.-A 2.3.7.6 Home Position Sensor The home position (HP) sensor is used for detecting the carriage home position. The details are described in below. Photo-electric conversion Detection System: Open-collector Output System: See Table 2-22. Signal Status: Table 2-22. HP Sensor Signal Status PAO (1 pin) of CPU (7B) Carriage position High...
  • Page 100 Backward : Fr I Ct i Otl Forward: T r a c t o r recocmlzes tnat Tne C P U C U T S H E E T E J E C T I N G r(?COOf3iZeS that i s c o n t i n u o u s DaDer c o n t i n u o u s DaDer backout mode.
  • Page 101 REV.-A CONTINUOUS PAPER LOADING CUT SHEET LOADING M o v e t h e carrla9e a t l - o 40”th c o l u m n s . Dr i v e t h e I un9er 1 5 0 ms.
  • Page 102 REV.-A CONTINUOUS PAPER BACK-OUT M o v e the cerrlaae a t 40”th c o l u m n s . ROtate t h e 9aDer reed motor ~c-l~o-cqkwi se. R o t a t e the DaDer r e e d motor count e r c I oc kw I se 1 0 0 SteDS.
  • Page 103 REV.-A PAPER HOLDING LEVER CLOSE P r i n t M o v e t h e C.Srria9exi) a t 40”th c o l u m n s . Rotate DMaPDe:u~feeed motor N-N+M TUrnS t h e oDr[tun9er D o w e r o D e r a t e whl (e 8 0 ms.
  • Page 104: Paper Feed Motor Speed Control

    REV.-A 2.3.8.2 Paper Feed Motor Speed Control When the amount of paper to be fed is 14 steps or less (amount of paper feed step is 1/180 inch), the paper feed motor is controlled to rotate at constant speed. When the amount of paper to be fed exceeds 14 steps, the paper feed motor is accelerated and decelerated.
  • Page 105: Paper Feed Motor Drive Circuit

    REV.-A 2.3.8.3 Paper Feed Motor Drive Circuit Figure 2-66 shows an open-loop circuit for constant voltage drive and the 2-2 phase excitation system driven by +35 V DC. A02 through D02 of the MCU (2A) control the coil excitation system, and POT3 between the hold/run modes.
  • Page 106: Sensor Circuits

    REV.-A 2.3.8.4 Sensor Circuits This control circuit employs two sensor circuit. One is the paper end sensor circuit which detects the paper stays or not in printer mechanism. The other is the release/friction sensor circuit which detects the paper release lever position. Paper End (PE) Sensor Detection System: Mechanical switch...
  • Page 107 REV.-A Release/Friction (R/F) Sensor Detection System: Mechanical switch Signal Status: See Table 2-26. Table 2-26. R/F Sensor Signal Status Paper Release Lever Position PB6 (15 pin) of CPU (7B) Forward (release) Backward (friction) High Circuit: See Figure 2-69. *’B’ Fig. 2-69. F/T Sensor Circuit 2-66...
  • Page 108: Plunger Drive Circuit

    REV.-A 2.3.9 Plunger Drive Circuit The CPU to open and close the paper holding controls this circuit to drive the plunger lever for paper shows the drive mechanism, Figure 2-71 shows the plunger drive auto loading/ejection. Figure 2-70 circuit and Figure 2-72 and Table 2-27 show the on/off timing of the transistors during the plunger drive and paper holding.
  • Page 109 (v) I 3 5 - 3 5 - Plunger Plunger Distance motion from Stopping Point @ Paper holding lever close state @ plunger drive state I @ Paper holding lever open state (@ Plunger hold state @: plun9er drive state II Fig.
  • Page 110: Control Circuit

    REV.-A 2.3.10 Printhead Control Circuit Figure 2-73 shows a block diagram of the printhead control circuit. In this circuit, the print data is stored in the head data control gate array E05A02LA (3A) by the CPU. The Cpu sends three sets of 8-bit data the E05A02LA via the print (for 24 dots), and then sends a printhead drive pulse to drive pulse width...
  • Page 111: E05A02La Gate Array

    REV.-A 2.3.10.1 E05A02LA Gate Array The E05A02LA Gate Array includes circuits to interface the CPU and printhead. This general purpose gate array has special commands that lighten the load on the CPU when outputting printhead data. of data Figure 2-74 is a block diagram of the E05A02LA gate array. The gate array mainly consists 24 bits latches: 8 bits X 3 = 24 bits.
  • Page 112 REV.-A Because the ~ terminal of this gate array is activated by accessing address FD2 X H, the command output address and data output address are determined as shown in Table 2-28. Table 2-28. E05A02LA Gate Array Functions Function 1/0 Address FD20H Outputs a command: Bit 7: Data latch writing sequence setup...
  • Page 113: Hpw Trigger Pulse Generation Circuit

    REV.-A (ED 20H ) + OOIOOOOOB —-mm---( “ DATA DATA x 3 COMAIUO DATA I H ) * O 0 H (F D 2 Pr in 1 i ng I n i t i a l i z e Woif # 9- 16 Fig.
  • Page 114 REV.-A COPY NORMAL MODE Pc 5 ‘Pcnnl-m — 5 5 5 E05A02LA “pw L — — according to the voltage of the +35 V line. NOTES: 1. This cycle varies 2. This drive pulse width depends on the value of PC5. Fig.
  • Page 115: Printhead Solenoid Drive Circuit

    REV.-A Adjuslmenl Mode (Heed GoP Lever Position: I-3 ) Mode ( 4 - 8 ) 220+-- ‘u ~’ 180. — E .- 31.’5 38.5 [v 1 Power Supply Limits 35 v t 10 “/0 Printheod C o i l Vo I toge ( +35V DC Line ; Y 2 ) D r i v e Fig.
  • Page 116: Platen Gap Sensor Circuit

    REV.-A 2.3.10.4 Platen Gap Sensor Circuit The platen gap (pg) sensor is used for detecting the Head adjustment lever position. The details are described in below. Mechanical Switch Detection System: See Table 2-30. Signal Status: Table 2-30. Platen Gap Sensor Signal Status PB7 (16 pin) of CPU (76) Head Adjustment Lever Position 1st to 3rd...
  • Page 117 REV.-A CHAPTER 3 OPTIONAL EQUIPMENTS 3.1 GENERAL ..................... 3-1 3.2 OpTloNAL INTERFACES .
  • Page 118: Optional Interfaces

    REV.-A 3.1 GENERAL This chapter describes the options available for the LQ-850/l 050. 3.2 OPTIONAL INTERFACES The LQ-850/l 050 uses the 8100 series optional interfaces. The main optional interfaces are listed in Table 3-1. Table 3-1. Optional Interfaces Description Cat. No. Function Buffer Size Standard...
  • Page 119 REV.-A 3 . 2 . 1 8 1 4 3 I n t e r f a c e B o a r d When the RS-232C and 20 mA neutral current loop are in use, the printer will also support the 8143 new serial interface.
  • Page 120 REV.-A DIP Switch Settings Table 3-3 shows the 8143 DIP switch settings, and Table 3-4 lists the bit rates selected by the DIP switch settings. When a standard 8-bit parallel interface is used instead of the 8143 l/F board , DIP switch 1-8 should be turned off.
  • Page 121 REV.-A CHAPTER 4 DISASSEMBLY, ASSEMBLY, A N D ADJUSTMENT GENERAL REPAIR INFORMATION ..........
  • Page 122 REV.-A 4.2.4.19 Paper Holding Roller Set and Paper Holding Levers L and R Removal ......4-36 4.2.4.20 Push Tractor Unit Disassembly .
  • Page 123 REV.-A Fig. 4-26. Transmission Gears Removal ..........4-22 Fig.
  • Page 124 REV.-A LIST OF TABLES Table 4-1. Repair Tools ................. 4- 1 Table 4-2.
  • Page 125: General Repair Information

    Electric soldering iron B740200 100 Brush No. 1 B74 1400200 Brush No. 2 B74 1400100 Cleaning brush B74 1600100 O: Commercially available product E: EPSON exclusive tool Table 4-2. Measuring Instruments Description Specification Necessary Convenient Multimeter Oscilloscope 20 MHz or more Logic analizer Table 4-3.
  • Page 126 REV.-A Figure 4-1 shows some of the parts found on the LQ-850/1050. Sheet Guide Printer Cover Piper Release Lever Control Panel Push Tractor /’” paPer~ensi~n”nit Roller Shaft 7- / Interface p o w e r Switch Connector Power Cord Fig. 4-1. Parts of the LQ-850/1050...
  • Page 127 REV.-A W A R N I N G ‘here are several precautions you should take after performin9 troubleshooting and when packing for transport: printer Slide the printhead to the middle of the printer. While holding the paper holding roller shaft open, reattach the locking tabs to left and right of the printer mechanism.
  • Page 128 REV.-A 4. Repack the printer using the original box and packing materials. 5. Also, before disassemble or checking the printer, remove the protective materials described above for packing procedures. by reversing the sequence used After printer disassembly, assembly, and adjustment, be sure to perform lubrication, adhesive application, cleaning, and maintenance as indicated in Chapter 6 to maintain optimal printer performance.
  • Page 129: Disassembly And Assembly

    4.2 DISASSEMBLY AND ASSEMBLY by performing the disassembly operation Components of the LQ-850/l 050 may be assembled simply been omitted. in reverse sequence. Assembly procedures, therefore, have into three parts: ( 1 ) removal of the upper The sequence of this disassembly in this section is grouped (2) removal of the circuit boards, and (3) disassembly of the printer mechanism.
  • Page 130 REV.-A Screws, washers, nuts, etc. are abbreviated using the conventions below. Table 4-4. Abbreviations List of Small Parts Part Name Abbreviation (CTBB) Cross-Bind-head B-tight (CTBS) Cross-Bind-head S-tight Cross-Bind-head S-tight with Outside-toothed washer CBS (0) (CTB (0)) Cross-Bind-Notch-head S-tight CBNS (CTBS (N)) CPS (0) (CTPS (0)) Cross-Pan-head S-tight with Outside-toothed washer Cross-Pan-head S-tight with Plain washer...
  • Page 131: Upper Case Removal

    REV.-A 4.2.1 Upper Case Removal To check the interior of this printer, first remove the upper case using the steps listed in the paragraphs below. DANGER Prior to beginning the following procedures, be sure to disconnect the power cord and interface cable, and remove the paper installed in the printer.
  • Page 132: Push Tractor Unit Removal

    REV.-A 4 . 2 . 2 P u s h T r a c t o r U n i t R e m o v a l Remove the push tractor unit before removing the circuit boards and the printer mechanism from the lower case.
  • Page 133: Circuit Board Removal

    REV.-A 4.2.3 Circuit Board Removal This printer includes two circuit boards: the MONMA controller circuit board and MONPS/MONPSE power supply circuit board. 4.2.3.1 MONMA Board Removal Remove the upper case (Refer to Section 4.2. 1.). Remove the push tractor unit (Refer to Section 4.2.2.). Disconnect connectors CN 17 and CN 18, which connect the MONPS/MONPSE board.
  • Page 134 REV.-A 7. Remove the two CBS (3 X 10) and two CBB (3 X 10) screws securing the MONMA board. 8. Release three tabs securing the MONMA board. 9. Remove the CPB (3X 12) screw and spacer securing the MONMA board. 10.
  • Page 135: Monps/Monpse Board Removal

    REV.-A 4.2.3.2 MONPS/MONPSE Board Removal 1. Remove the upper case (Refer to Section 4.2. 1.). 2. Remove the push tractor unit (Refer to Section 4.2.2.). 3. Disconnect connector CN 1 which connect the MONMA board and CN2 which connect the fan unit. 4.
  • Page 136: F A N U N I T R E M O V A

    REV.-A 4.2.3.3 Fan Unit Removal Remove the upper case (Refer to Section 4.2. 1.). Remove the push tractor unit (Refer to Section 4.2.2.). Remove the MONPS/MONPSE board (Refer to Section 4.2.3.2.). Remove the two CBB (4 X 12) screws securing to lower case. Remove the fan unit.
  • Page 137: Printer Mechanism Disassembly

    REV.-A 4.2.4 Printer Mechanism Disassembly This section describes the procedures for disassembling the main components of the printer mechanism. Figure 4-14 shows the relationship of the printer mechanism’s majour components for reference during assembly. Refer to Figures A-37 through A-44 in the Appendix during assembly. —...
  • Page 138 START nt:~y:tpm Pr lnthe~d R~v.31 4, 2.4. 19 4 - 3 6 4, 2. 4.4 4- te 4. 2.4.6 4-21 4.2.4. 10 4-25 4.2.4, 11 4-26 I I 4. 2.4.7 4-22 II 4. 2.4, 6 4-23 Car rRl~eva~t or Pr Inter t4acan R I tJl)On M4Sko R 11300nR~9vkalH0 tder 01 sassarml...
  • Page 139: Printer Mechanism Removal

    REV.-A 4.2.4.1 Printer Mechanism Removal 1. Remove the upper case (Refer to Section 4.2. 1.). 2. Remove the platen knob. 3. Remove the push tractor unit (Refer to Section 4.2.2.). 4. Disconnect connectors CN 12, CN 15, CN 16, CN8, CN9, CN 10, CN 14, CN 13, and CN 11 from the MONMA board (Refer to Figure 4-8.) 5.
  • Page 140: Printhead Removal

    REV.-A 7. Remove the printer mechanism. 8. Remove three for the LQ-850 or four screws for the LQ-105O, CPS(0) (3 X 6), securing the ground plates to the base frame of the printer mechanism. Ground Plate Fig. 4-16. Ground Platas Removal 4.2.4.2 Printhead Removal 1.
  • Page 141: Fpc (Flexible Printed Cable) Removal

    REV.-A 5. Disconnect the two flexible printed cables (FPCS) from the connectors at the printhead. Printhead FPC R ~FpcF Fig. 4-18. Disconnecting FPC ASSEMBLY POINT Insert FPCS to the connector as shwon in Figure 4-18. — 4.2.4.3 FPC (Flexible Printed Cable) Removal Remove the printer mechanism (Refer to Section 4.2.4.
  • Page 142: Carriage Motor Removal

    REV.-A 4.2.4.4 Carriage Motor Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Remove the carriage motor wires from the wire holder. 3. Remove the timing-belt tension spring. 4. Remove the two CPS (0)(3 X 10) screws securing the carriage motor mounting plate to base frame via carriage motor mounting bush.
  • Page 143 REV.-A ASSEMBLY POINT 1. Set the timing belt correctly at the drive pulley of the carriage motor. 2. Mount the carriage motor with carriage motor mounting plate and carriage motor mounting bushes on base frame by lightly tightening two CPS (0) (3 X 10) screws. 3.
  • Page 144 REV.-A R e m o v a l 4.2.4.5 Timing Belt* Belt-Driven Pulley Remove the printer mechanism (Refer to Section 4.2.4.1 .). Remove the timing-belt tension spring. Loosen the two CPS(0)(3 X 10) screws which fixing carriage motor mounting plate to the base frame. Pull the timirm belt out from carriage motor pulley.
  • Page 145: Home Position Sensor Removal

    REV.-A 4.2.4.6 Home Position Sensor Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Press the two tabs of the home position sensor on the bottom of the base frame. 3. Remove the home position sensor. 4. Disconnect the connector from the home position sensor. Home Position ~ensor Connector (b) Top View...
  • Page 146 REV.-A 4.2.4.7 Paper Feed Motor* Transmission Gears Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1 .). 2. Remove the two CPS(0) (3 X 6) screws. 3. Remove the paper feed motor. Motor >Paper Feed Fig. 4-25. Paper Feed Motor Removal 4.
  • Page 147: Platen Gap Sensor Removal

    REV.-A 4.2.4.8 Platen Gap Sensor Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Position the head adjustment lever at a setting between the 4th and 8th positions. 3. Remove the CPS(P) (3 X 10) screw securing the platen gap sensor to the side frame L, remove then the sensor.
  • Page 148: Friction/Tractor Sensor Removal

    REV.-A 4.2.4.9 Friction/Tractor Sensor Removal Remove the printer mechanism (Refer to Section 4.2.4. 1.). at the its Position the paper release lever back setting. Remove the paper feed motor (Refer to Section 4.2.4.7). sensor to the side frame R, then Remove the CPS(P) (3 X 10) screw securing the friction/tractor remove the sensor.
  • Page 149: Plunger Removal

    REV.-A 4.2.4.10 Plunger Removal 1. Remove the RE (3), and disconnect loading lever of the plunger from the paper holding lever L. 2. Remove two CPS (0) (3 X 6) screws, which secure the plunger to the side frame L, then remove the plunger.
  • Page 150: Platen Unit Removal

    REV.-A 4.2.4.11 Platen Unit Removal 1. Remove the upper case (Refer to Section 4.2. l.). 2. Remove the two CBNS (3 X 6) screws securing the platen cover to side frames L and R, then remove the platen cover. Shaft Holder Paper Holding Roller Shaft CBNS (3 X 6 ) Fig.
  • Page 151: Paper Release Lever Removal

    REV.-A 4.2.4.12 Paper Release Lever Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Remove the paper feed motor and transmission gears (Refer to Section 4.2.4.7.). 3. Remove the platen unit (Refer to Section 4.2.4.1 1.). 4. Press the paper release lever tab at the inside of the side frame R, then remove the lever. Paper Release Lever Fig.
  • Page 152: Printer Mechanism Disassembly

    REV.-A 4.2.4.13 Printer Mechanism Disassembly 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Remove the printhead (Refer to Section 4.2.4.2.). 3. Remove the carriage motor (Refer to Section 4.2.4.4.). 4. Remove the belt-driven pulley (Refer to Section 4.2.4.5.). 5.
  • Page 153 REV.-A 9. Remove two CPS (0) (3 X 10) screws securing both R to the base frame. side frames L and kide Frame L i3-x Side Frame R .— — Fig. 4-36. Screws Removal 10. Detach the hooks on the main unit from the base frame, and pull the main unit up. Fig.
  • Page 154 REV.-A Fig. 4-38. Main Frame Unit Ribbon Driver Unit Fig. 4-39. Base Frame Unit ASSEMBLY POINT When fitting the main frame to the base frame, hook the eight tabs into the holes in the base frame, and pull it forward. ADJUSTMENTS REQUIRED The following adjustments are required to reassemble the printer mechanism: 4.3.2 Paper Feed Motor Backlash Adjustment...
  • Page 155: Ribbon Driver Unit Removal

    REV.-A 4.2.4.14 Ribbon Driver Unit Removal 1. Remove the printer mechanism (Refer to Section 4.2.4. l.). 2. Separate the main and base units (Refer to Section 4.2.4.1 3.). 3. Press the six tabs for the ribbon driver unit at the bottom of the base frame, and remove it. —...
  • Page 156: Carriage Removal

    REV.-A 4.2.4.15 Carriage Removal 1. Remove the printer mechanism (Refer to Section 4.2.4.1.). 2. Separate the main and the base units (Refer to Section 4.3.4. 12.). 3. Remove the RE (3) securing the loading lever of the plunger to paper holding lever L. 4.
  • Page 157 REV.-A . . . , , . . , : . , J’ —— ‘-”””-”’ Side Frame R Side F;ame L Carriage’ Guide Shaft A Carriag’a Guide Shaft B — Fig. 4-42. Carriage Guide Shafts A-and B Removal 7. Pull the carriage out from the carriage guide shafts A and B. ASSEMBLY POINTS 1.
  • Page 158: Paper Guide Plate Removal

    REV.-A 4.2.4.16 Paper Guide Plate Removal 1. Remove the printer mechanism (Refer to Section 4.2.3. 1.). 2. Separate the main and base units (Refer to Section 4.2.4.1 2.). 3. For the LQ-850, remove the two paper guide plate springs or for the LQ-1 050 remove three paper guide plate springs with the mechanism status.
  • Page 159: Paper Feed Roller Unit Removal

    REV.-A 4.2.4.17 Paper Feed Roller Unit Removal 1. Remove the printer mechanism (Refer to Section 4.2.3.1 .). 2. Separate the main and base units (Refer to Section 4.2.4.1 2.). 3. Remove three paper feed springs for the LQ-850 or four for LQ-1 050 from the hook on the base frame.
  • Page 160 REV.-A 4.2.4.19 Paper Holding Roller Set and Paper Holding Levers L and R Removal 1. Remove RE (3) at the outside of the paper holding lever R on the paper holding roller set. 2. Remove the right and left sides of the paper holding roller shaft from the paper holding levers. 3.
  • Page 161 REV.-A 4.2.4.20 Push Tractor Unit Disassembly This section describes the removal of the tractor assembly (left). Since disassembled parts can be reassembled by using the removal procedures in reverse orde~ assembly procedures have been omitted. shaft holder from the tractor mounting plate L. Remove the CPS (0) (3 X 6) screw securing tractor mounting plate L to the tractor base frame.
  • Page 162 REV.-A 4.2.4.21 Paper Tension Unit Disassembly This section describes the removal of the paper tension roller assembly. Since disassembled parts can be reassembled by using these procedures in reverse order, the assembly procedures have been omitted. 1. Remove the RE (4) on the paper tension roller shaft at the inside of the paper tension frame R. 2.
  • Page 163 REV.-A 4.3 ADJUSTMENT This section describes the adjustment procedures required when reassembling this printer. When disassembly or replacement is performed during maintenance or repaires “of the parts described in this section, the following adjustments should be performed to ensure proper operation. 4.3.1 Platen Gap Adjustment Adjust the gap between the platen and the printhead when carriage guide shaft B is rotated or removed.
  • Page 164 REV.-A ~Thickness Gauge < Countersink > Small Lerge Carriage G;ide Shaft B Fig. 4-55. Platen Gap Adjustment — Set the head adjustment lever at the 2nd position. Push the paper release lever all the way back. Gap value: 0.45 & 0.05 mm Adjust the platen gap using a thickness gauge while rotating carriage guide shaft B in the direction of the arrow in Figure 4-56.
  • Page 165 REV.-A 14. Hold carriage guide shaft B in place and tighten the HNO (4) nut. 15. Move the carriage to the left end, and measure the gap value again to confirm that it is correct. 16. Move the carriage to the right end, and measure the gap value again to confirm that it is correct. 17.
  • Page 166 REV.-A 4.3.2 Paper Feed Motor Gear Backlash Adjustment This adjustment is required either when the paper feed motor is replaced or when its mounting position is shifted. 1. Remove the printer mechanism (Refer to Section 4.2.4.1 .). 2. Loosen the two CPS(0) (3 X 6) screws on the paper feed motor. 3.
  • Page 167 REV.-A 4.3.3 Electric Board Adjustment This section describes the MONMA board adjustment. If replace the MONMA board or printer mechanism, perform the adjustment in below. 4.3.3.1 Bidirectional Value Adjustment If printing is misaligned in during bidirectional printing, align the printer by adjusting VR2 and VR3 on the MONMA board, according to the alignment sequence flowchart shown in Figures 4-59 and 4-60 (Refer to Figure 4-61 for the positions of the switches and VRS).
  • Page 168 REV.-A Remove the id9e Cartr c o v e r and the r2rlnter cover. Loaa the mmer. T u r n t h e Dower on wnl Ie cleDressin9 CONDENSED and LOAIYEJECT. adjust VR2 or VR3? FORM-FEED. DeDress — A I I 9n the Dr i nt i n9 I t I on.
  • Page 169 DeDress FORM-FEED. s e l e c t VR3(FF) adjust adjustment or enter this mode (ON-LINE)? DeDreSS ON-L I NE. I lnitlal Ize the Dr Inter. I cD-- P r i n t c h a r a c t e r t h r e e I Ines at moae-3.
  • Page 170 REV.-A Printing Position Alignment Check Figure 4-62 shows three lines of test printing with characters “l”. Using this printout, check the following: Odd Line ... . Reference Even Line ... Move VR2=-1 mode=O Fig.
  • Page 171: Troubleshooting

    REV.-A CHAPTER 5 TROUBLESHOOTING GENERAL ....................5- 1 5.1.1 Diagnostic Tools .
  • Page 172 REV.-A LIST OF TABLES Troubleshooting Tools ............
  • Page 173 REV.-A 5.1 GENERAL can occur, troubleshooting is not easy to perform. Here, a simple Because various types of trouble troubleshooting, as shown in Figure 5-1. procedure is provided to perform 5. I .1 5 - 3 Fault check using the Unit Replacement diagnastlc tool F’%...
  • Page 174 REV.-A Table 5-1. Troubleshooting Tools Part No. Description Tool No. Item B765 108801 Use together with EPSON PC (EQUITY) series E638 Diagnostic Tool B765 108901 E639 Use together with EPSON QX-16 B765 105401 E594 Cable (2pin) Between MONMA board (CN9) and paper end...
  • Page 175 5.1.1 Diagnostic Tools The diagnostic tools enable anyone to troubleshoot the electric components, regardless of their experience. 5.1.1.1 System Outline (EPSON QX16 or PC (EQUITY), etc.) This system is connected to an MS-DOS-based computer using an RS-232C cable. First, install the diagnostic cartridge in the printer and run the diagnostic program with the computer.
  • Page 176: Unit Replacement

    REV.-A 5.2 UNIT REPLACEMENT The unit replacement is based on system analysis. According to the particular symptom found by the multi meter, the units listed in Table 5-3 need to be replaced. Table 5-3. Unit Replacement Numbers Unit No. Description Unit Name X50206 1060 120V 3.
  • Page 177 1. Printer does not operate with power switch ON (power does not bright.) Use correct voltage. In put Replace the fUSe turned ON again. is the new fuse also .— Measure the output voltage f r o m MONPS/MONPSE b o a r d . Replace the MONPS/MONPSE board.
  • Page 178 REV.-A 2. The carriage does not operate correctly. CN9. CN 10. CN 11. CN 12, CN 13. CN 14, CN 15. andCN 16 connecting the MONMA board and printer mechanism, inserted Secure connectors. Replace the printer mechanism. < Replace the MONMA board.
  • Page 179 normally, but the self-test printing 3. The carriage operate ttw head odjustmmt I*v*r position. at TM Znd perform self-test. prlntlng ‘~xecufed? hroIJ@ C N 16 COWlOCtil_$g bard aid ttw p r i n t e r MONMA any dot “missing? Ralnsert them cwrectly.
  • Page 180 REV.-A 4. The self-test printing is normal, but the paper is not fed properly. paper correctly. Set the platen knob rotate smoothly when turned Replace the MONMA board. Replace battery. mechtmism. Replace the printer...
  • Page 181 5. The control panel does not operate correctly. control pane etween the tmd the MONMA board Reinsert connector CN7 correctly. — Replace the MONMA board. Replace the control panel. Replace the MONMA board.
  • Page 182 REV.-A 6. The printing is incorrect in the ON-LINE mode. NOTE: It is assumed that the host computer operates normally. Perform test printing. ~:ef:~ to other troubleshooting Confirm the transmission conditions of the printer and the host computer. Replace the MONMA board. 5-1o...
  • Page 183 TAble 5-5. MONPS Board Environmental Condition (Reference Value) Output Voltage [V] Power Supply Line 40”C O“c 25°C 35.4 35.5 35.5 + 3 5 - G + 1 2 - GND – 10.0 – 9 . 9 – 10.0 – 1 2 - GND + 5 - GND NOTES: 1.
  • Page 184 REV.-A 5.3 UNIT REPAIR Unit repair is divided into three parts: (1) The MONPS/MONPSE board; (2) The MONMA board; (3) The Printer mechanism. This section will describe (1), the MONPS/MONPSE board unit repair. If (2) MONMA board or (3) Printer mechanism should need repair, use the diagnostic tool introduced in Section 5.1.1.
  • Page 185 REV.-A Table 5-7. MONPS/MONPSE Board Unit Repair Solution Cause Checkpoint Symptom Replace IC20. +5 V line is dead. IC20 malfunction Refer to the checkpoint list for the +35 V line is dead. +35 V line. +35 V line is Check whether the Input filter circuit Check the input voltage waveform input filter circuit...
  • Page 187 REV.-A Fig. 5-6. MONPS/MONPSE Board Voltage Waveforms 5-14...
  • Page 188 5-16...
  • Page 189 REV.-A 5-17...
  • Page 190 REV.-A Table 5-8. MONPS/MONPSE Board Main Parts List MONPSE Board MONPS Board Location Name Description Description Name ~D20,zD21 HZ 20-3TD 2 0 . 2 - 2 1 . 1 v 500mW 200mA 2SA 10 15-TPE2 50V, 150mA 400mW 800V, 10A 600V, 15A, 130W 2SC4313 2SC4059...
  • Page 191 REV.-A 5.3.2 MONMA Board The MONMA board can be repaired using the diagnostic tool. Table 5-9 lists the main parts of the MONMA board. Table 5-9. MONMA Board Main Parts List Description Name Location Hex inverters with open-collector output 74LS05 Hex buffer with open-collector output 74LS07 Quad line drivers...
  • Page 192 REV.-A 5 . 3 . 3 M o d e l - 5 3 1 0 / 5 3 6 0 P r i n t e r M e c h a n i s m Use the diagnostic tool to detect malfunctions among the carriage motor, paper feed motor, sensor and plunger.
  • Page 193 REV.-A CHAPTER 6 MAINTENANCE 6.1 PREVENTIVE MAINTENANCE ............. .6-1 6.2 LUBRICATION AND ADHESIVE APPLICATION .
  • Page 194: Preventive Maintenance

    EPSON recommends that the points illustrated in Figure 6-2 be lubricated according to the schedule listed in Table 6-2, with EPSON O-2 and G-27, which have been extensively tested and found to comply with—the need of this printer (Refer to Table 6-1 for details 070-2 and G-27.). Lubrication should be performed regularly according to the A and B classification of Table 6-2.
  • Page 195 REV.-A Table 6-3. Adhesive Application Point (Refer to Figure 6-2.) Number of point Adhesive Application Point Ref. No. (11) Engaging parts between timing belt and carriage Fig. 6-1. LQ-850 (LQ-105O) Lubrication Points Diagram...
  • Page 196 REV.-A — Fig. 6-1. LQ-850 (LQ-105O) Lubrication Application Points Diagram (Cont.)
  • Page 197 REV.-A Carriage Position Neji Lock #2 (b) Bottom View Fig. 6-2. Adhesive Application Point...
  • Page 198 REV.-A APPENDIX A.1 IC DESCRIPTIONS ................A- 1 A.1.l PPD781OHG CPU (76) .
  • Page 199 REV.-A LIST OF FIGURES pPD781 OHG Pin Diagram ............A- 1 Fig.
  • Page 200 REV.-A Fig. A-36. MONMA Board Circuit Diagram ......... . A-47 Fig.
  • Page 201 REV.-A Table A-24. CN13 Pin Assignments ............A-38 Table A-25.
  • Page 202 REV.-A A.1 IC DESCRIPTIONS This section describes the primary ICS used in the LQ-850/ 1050, and supplements the data provided in Chapter 2. A.1.l /.LPD7810HG CPU (7B) The gPD78 10HG is an 8-bit CPU and includes two 8-bit timercounters, an 8-bit A/D converter, 256 bytes of RAM, and a serial interface.
  • Page 203 ‘j I I 3 H ( 1 9 lklOd ILIOd 4 IHOd ILIOd lklOd ‘ Fig. A-2. KPD781OHG Block Diagram...
  • Page 204 REV.-A Table A-1 lists the terminal functions of the IC 7B. Table A-1. 1.LPD781 OHG Terminal Function Status Description I Pin No, I Signal I Dir. HOME/OUT Carriage home position signal Paper end signal STAY/OUT ACT/NON PLUNGER2 drive PA 2 O N / ~ PA 3 Buzzer...
  • Page 205 Table A-1. I.LPD781OHG Terminal Function (cont.) Status Description Dir. Pin No. Signal — + 35V AN 1 line monitoring O F F / ~ AN 2 DIP SW 1-5 read O F F / ~ DIP SW 1-6 read AN 3 DIP SWS 1-3, 1-8, 2-2, 2-6 read O F F / ~ AN 4...
  • Page 206 REV.-A CPU Timing (Figures A-3 through A-5) Three oscillations define one state. The OP code fetch requires four states: during T1 to T3, program T1 to memory is read; instructions are interpreted during T4. Address bus 15 - 8 are output from T4.
  • Page 207: Eo5A1Oaa Gate Array (1Oc)

    REV.-A ( 1 O C ) A.1.2 EO5A1OAA Gate Array The gate array is a memory management unit IC which contains reset circuit, address latch, memory management unit, and so on. MMI03 fmllo4 AB15 A138 AB14 AB{I ;f;o AB 3 i3&K0 BANK4 BANK5...
  • Page 208 GND VOO (+5vJ 5 - 8 A L E De 7 - o %=====-””0 MAN AGEMENT CONTROL PANEL I / F P O RT 0-.2 M M IO O DATA MMIO I 2ROCESS1NG M M IO 2 M M 1 0 3 tdh.1104 .
  • Page 209 REV.-A Table A-2. E05A1 OAA Terminal Function Function Name Dir. Pin No. Bank select O BANKO Bank select 1 BANK1 Bank select 2 BANK2 BANK3 Bank select 3 BANK4 Bank select 4 Bank select 5 BANK5 AD O Address bus O AD 1 Address bus 1 AD 2...
  • Page 210 REV.-A Table A-2. EO5A1OAA Terminal Function (cont.) Function Dir. Pin. No. Signal MMI04 N.C. CSBOO IC 4A select CSB40 IC 6A select (correspond to J4) CSBCO CG3 (CN4) = (CN5) CSBDO m (CN6) CSBEO IC 6A and IC 8A select (correspond to J4) CSBFO Read strobe Write strobe...
  • Page 211: E05A09Ba Gate Array (2A)

    REV.-A A.1.3 E05A09BA Gate Array (2A) The gate array is 4 phases stepper motors control IC which contains two motor’s phase excitation control circuit. POT 2 VD D co I Tii7 POT O POT I BO I AO I PO T3 AD O AD I D 0 2...
  • Page 212 REV.-} Table A-3. E05A09BA Terminal Function Description Pin No. Name Dir. Address bus O Address bus 1 AD 1 Address bus Address bus 3 TM 1 Carriage motor clock pulse Paper feed motor clock pulse ~ pulse ~ pulse POT3 Paper feed motor RUN/HOLD Paper feed motor phase A Paper feed motor phase C...
  • Page 213: E05A02La Gate Array (3 A

    REV.-A A.1.4 E05A02LA Gate Array (3A) This gate array is used to simplify the interface between the CPU and the printhead. H] 1 Fig. A-10. E05A02LA Pin Fig. A-1 1. E05A02LA Block Diagram Diagram...
  • Page 214 REV.-A Table A-4. E05A02LA Terminal Function Function Pin No. Signal Head Data 1 - 8 output — Write enable Address bit O Chip enable Head Data 9 - 16 output — DATA/COMMAND INPUT .— - 2 9 RESET Head Driving Pulse width READY REDY —...
  • Page 215 REV.-A A.1.5 M5461OP 8-Bit Parallel VF (5A) The IC contains 8-bit parallel interface function so that the interface between host computer and CPU is simplify. 4 2 — V c c m— 41 — mz— 40 — B 0 3 13Tz —...
  • Page 216 REV.-A $: ‘ ~ “H” “H” ‘- ‘RR 34 “ : 5 ~T ‘R ‘RR 33 60 . %=El=. Fig. A-1 3. M5461OP Internal Circuit A-1 5...
  • Page 217 Table A-5. M5461OP Terminal Function Function Direction Name Pin No. - Host BUSY signal BUSY DIN8 + l-lost 8-parallel data DIN 1 + Host STROBE pulse Output timing of the BUSY signal O: Positive edge of STROBE 1: Negative edge of STROBE 6,21,35 DOU 1 + CPU...
  • Page 218: Stk6722H 4-Phases Stepper Motor Driver (1 A

    REV.-A A.1.6 STK6722H 4-Phases Stepper Motor Driver (1A) IC for the four phases stepper motor. The STK6722H is a uni-pauller constant current chopper driver t 2 3456 - - - - - - - - - 18 — Fig. A-14. STK6722H Pin Diagram I 13 ! ! ! ! ! ! ? p - - - - - - -...
  • Page 219 3EV.-A Table A-6. STK6722H Terminal Function Function Diraction Pin No. Signal + 35V DC power Vcc 1 CR nwtor phases A and B common Surge voltage of CR motor coils S.out CR motor phase A drive CR motor phase A drive pulse CR motor phase B drive pulse CR motor phase B drive Reference voltage for CR motor phases...
  • Page 220 REV.-A A.1.7 HM27256G-25 EP-ROM ( 9 A ) This EP-ROM is a ultra-violet erasable and electrically programmable ROM of 32 K-bytes. Features 20 ‘#Cc Vpp 1 Capacity of 32768 words X 8 bits 27 A!4 compatible with TTL 26 A! 3 Power supply +5V DC Access 250 ns...
  • Page 221 REV.-A Table A-7. HM65256 EP-ROM Signal Status outputs Mode Read D out High Z Output Disable High Z Standby High Performance Program Program Verify D out D out Optional Verify Program Inhibit High Z Identifier Code NOTES: 1. X . . . Don’t care 2.
  • Page 222: Hm65256Blsp-12 Cmos Pseudo St-Ram (7 A

    REV.-A A.1.8 HM65256BLSP-12 CMOS PSEUDO ST-RAM (7A) which has low power consumption, and its input/output level is This is a 8K-byte CMOS static RAM compatible with the TTL ICS. Features Capacity of 32768 words X 8 bits 1/0 with TTL compatible .
  • Page 223: Hm6264Alsp-12 Cmos St-Ram (8 A)

    REV.-A A.1.9 H M 6 2 6 4 A L S P - 1 2 C M O S S T - R A M ( 8 A ) This is a 8K-byte CMOS static RAM which has low power consumption, and its input/output level is compatible with the TTL ICS.
  • Page 224 Table A-9. HM6264ALSP-12 Signal Status 1/0 Terminal Mode Power down High Z High Z Output disable Read cycle Data out Write cycle (1) Data in Write cycle (2) Data in A-23...
  • Page 225: A.1.1O Sn75188N Line Driver (1 Oa

    REV.-A A.1.1O SN75188N Line Driver (1OA) The 75188 is a quad line driver IC which is used for exchanging the signal level from ITL to RS-232C with the 75189. Vcc 1 14 Vcc INPUT A 2 i3 INPUT 0! OUTPUT A 3 12 INPUT D2 INPUT W 4 11 OUTPUT D...
  • Page 226: Ne555P General Purpose Timer (7C

    REV.-A A.1.12 NE555P General Purpose Timer (7C) The 555 is a one circuit general purpose timer, which can be used to construct a timing generator circuit such as a one-shot/multi oscillator using a few external parts. Features . Wide timing range (1.Ls to hours) Valious timing circuits can be constructed .
  • Page 227 REV.-A A.1.13 74LS05 Inverter with Open-Collector Output (4B) This IC has hex open-collector invertors. ITiHi51mmlidmla Fig. A-26. 74LS05 Pin Diagram A.1.14 74LS07 Dutter with Open-Collector Output (6B) This IC has hex open-collector buffers. Fig. A-27. 74LS07 Pin Diagram A-26...
  • Page 228: Tl431Clpb Shunt Regulator

    REV.-A A.1.l 5 TL431 CLPB Shunt Regulator (CY1..MONMA Board, Q5.Q20..MONPS/MONPSE Board) high accuracy temperature compensated shunt regulator. The output voltage can be The TL431 is a changed between 2.5 to 36V by adding two external resistors. The TL43 1 has high stability and outputs a large current so that it can replace various zener diodes.
  • Page 229: Type Switching Regulator (Ic20

    REV.-A (IC20) A.1.16 STR20005 Chopper-Type Switching Regulator The STR20005 is a chopper type switching regulator IC which obtains a stable output voltage of +5V. /. .=..> Fig. A-29. STR20005 Pin Diagram TR I : R3 ~ R4 MIC I — -( b-—~ ,>...
  • Page 230: Connector Pin Assignments

    PIN ASSIGNMENTS A.2 CONNECTOR connector pin assignments in the electric circuit boards. Thes section describes the A.2.1 MONMA Board A.2.1.1 CN1 Use: To connect the printer to the host computer. Number of Pins: 36 Table A-1 2. CN1 Pin Assignments Return Signal Description...
  • Page 231 3EV.-A Table A-12. CN1 Pin Assignments (Cont.) Signal Return Dir. Description Signal Pin No. Pin No. The level of this signal becomes “LOW” when the printer is in: ERROR — 1. PAPER END state 2. OFF-LINE state 3. Error state —...
  • Page 232 REV.-A A.2.1.2 CN2 board. data between Use: Number of pins: 26 Table A-1 3. Pin Assignments Description Dir. Pin No. Signal Error ERROR Paper end Data bit 6 D6 (B4) BUSY (READY) BUSY Data bit 5 D5 (B3) Acknowledge ACKNLG D4 (Par-dis) Data bit 4 (Parity disable) Initialize...
  • Page 233 REV.-A A.2.1.3 CN3 To connect the printer to the host computer which has the RS-232C interface. Use: Number of pins: 6 Table A-14. CN3 Pin Assignments Pin No. Signal Dir. Description Transmit data for X-ON/X-OFF handshake. DTR (REV) Indicates whether data input is ready or not. When data input is inhibited, REW=’’MARK”.
  • Page 234 REV.-A A.2.1.4 CN4 (Contained only JAPAN) board. M O N M A To exchange data between the EMKG board and the Use: Number of pins: 44 Table A-1 5. CN4 Pin Assignments Description Signal Dir. Pin No. Al 2 Address bus 12 bus 7 Address...
  • Page 235 Table A-1 5. CN4 Pin Assignments (Cont.) Description Pin No. Signal Dir. + 5V DC power — Bank 4 — Not connected Bank 1 KANJI Address latch enable CG3 select PROG PROG select Write pulse Reset signal A-34...
  • Page 236 A.2.1.5 CN5 Interface with optional cartridge Use: Number of pins: Table A-16. CN5 Pin Assignments Description Pin No. Signal Dir. Data bus 5 Data bus 4 Data bus 7 Bank 1 AB 1 Address bus 5 Address bus 6 Address bus 10 A lO Reset signal —...
  • Page 237 REV.-A A.2.1.6 CN6 Interface with optional cartridge Use: Number of pins: 32 Table A-1 7. CN6 Pin Assignments Description Dir. Pin No. Signal Data bus 5 Data bus 4 Data bus 7 AB 1 Bank 1 I O I Address lAddressbus6 I 7 I Address...
  • Page 238 REV.-A A.2.1.7 CN7 Control panel interface Use: Number of pins: 12 Table A-1 8. CN7 Pin Assignments Description Pin No. Signal Dir. Switches status select O SB 1 Switches status select 1 Read switches status Read switches status Buzzer BUZZER RYLED READY LED ti/off PELED...
  • Page 239 REV.-A A.2.1.1O CN1O Detect paper thickness lever position Use: Number of pins: 2 Table A-21. CN1O Pin Assignments Description Dir. Pin No. Signal Head adjustment lever position ~/4-8 GAPSW — A.2.1.11 CN11 Friction or tractor feed Use: Number of pins: 2 Table A-22.
  • Page 240 A.2.1 .14 CN14 Carriage motor drive Use: Number of pins: CN14 Pin Assignments -Description Signal Dir. Pin No. Phase A drive pulse Phase B drive pulse Phase C drive pulse Phase D drive pulse COMAB Common phases A and B COMCD Common phases C and D A.
  • Page 241 REV.-A A.2.1 .16 CN16 Printhead solenoids drive Use: Number of pins: 15 Table A-27. CN16 Pin Assignments Function Pin No. Name Dir. Drive pin 6 HD14 Drive pin 14 Drive pin 10 HD 10 HD23 Drive pin 23 HD18 Drive pin 18 Drive pin 15 HD 15 HD22...
  • Page 242: Monps/Monpse Board

    REV.-A A.2.1 .19 CN19 Back power is supplied Use: up battery Number of pins: 2 Table A-30. CN19 Pin Assignments Function Nama Dir. Pin No. Battery + side BATT — A.2.2 MONPS/MONPSE Board A.2.2.1 MONMA Send various powers board. Use: Number of pins: 10 Table A-31.
  • Page 243: Exploded Diagrams And Schematics

    REV.-A A.2.3 EXPLODED DIAGRAMS AND SCHEMATICS Fig. A-31. MONPS Board Component Layout A-42...
  • Page 244 REV.-A f’ ‘r ”v Uxooz m+ool 8 C8U31 POO-ZWU3 ———— — ‘ :“ Fig. A-34. MONPS Board Circuit Diagram A-45...
  • Page 245 IC*ll S-OZZH.Z Oocc Ozaz !Zaz L – – – – J Fig. A-35. MONPSE Board Circuit Diagram...
  • Page 246 REV.-A Fig. A-32. MONPSE Board Component Layout A-43...
  • Page 247 ‘QEg’jq’ G053 ‘m’ ’ wlm” ‘=” ’ C)”35 0 9 w ‘Q -a 021 & - 6 6 o22~ % R63 II- C15 w R65 w R65 w R67 * R6a RI06 ‘e= Fig. A-33. MONMA Board Comp~~ent Layout A-44...
  • Page 248 REV.-A Fig. A-32. MONPSE Board Componant Layout A-43...
  • Page 249 Japan Printed in 87.08- 1.5 , . ,...

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Lq-850

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