It is intended for use as a reference for periodic inspections and maintenance procedures. This manual is prepared for use at a technical level and not for the general user. Model Destination NX-1500 MULTI-FONT For American and Asian market LC-15 MULTI-FONT For European and Pacific market •...
Paper feed speed 2.8 inches/second max. Character set ASCII Code table (International) 3 sets *1 (For NX-1500 SU, LC-15 SU)/14 sets *2 (Others) IBM special IBM block graphic Download *1 IBM-Russian, Gost, Code page #866 *2 USA, France, Germany, England, Denmark I, Sweden, Italy, Spain I, Japan, Norway, Denmark II, Spain II, Latin America,...
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GENERAL SPECIFICATIONS Maximum buffer size Without Download 15KB With Download 1 line Emulations Epson mode IBM proprinter mode Interface Standard: Centronics parallel Option: RS-232C serial Ribbon type On-carriage, dedicated Black Ribbon life 3 million characters (draft pica) 590(w) × 332(d) × 127(h)mm Dimensions 23.2(w) ×...
GENERAL SPECIFICATIONS DIP Switch Settings 3-1. For NX-1500 SU, LC-15 SU Switch Function Page length 11 inches 12 inches Auto CR Character Set Gost Other (See 2-4) Auto sheet feeder Inactive Active Paper-out detector Enabled Disabled Emulation mode Standard Character set...
GENERAL SPECIFICATIONS Parallel Interface 4-1. General Specifications Item Specifications Synchronization System Via externally supplied STROBE pulses I/F Protocol By ACK and BUSY signals Logic Level Compatible with TTL level Fig. 1-4 Timing Charts of Parallel Interface 4-2. Connector Signals Pin No Signal Name Function Description Goes from high to low (for ≥...
GENERAL SPECIFICATIONS Serial Interface (option) 5-1. General Specifications Item Specifications Interface RS-232C level Synchronization System Asynchronous Baud rate 150-19,200 bit per second (BPS) [selectable] 150, 300, 600, 1200, 2400, 4800, 9600, 19200BPS Word length Start bit: 1 bit Data bit: 7 or 8 bits (selectable) Parity bit: Odd, Even or None (selectable)
GENERAL SPECIFICATIONS 5-3. DIP Switch Settings Switch 8 data bits 7 data bits No parity Parity checked Handshaking protocols — see table below Odd parity Even parity Data transfer rate — see table below All switches are set ON when the printer leaves the factory. Protocol Switch 3 Switch 4...
THEORY OF OPERATION Block Diagram The block diagram of this printer is shown in Fig. 2-1. Fig. 2-1 Block Diagram Main Logic Board This board receives data from the host computer and stores it in the RAM in the order of arrival. The CPU on this board reads the data from the RAM, and edits it according to the program stored in the ROM.
THEORY OF OPERATION Main Logic Board 2-1. Data Input Operation 2-1-1. Parallel Interface Communications between the host computer and this printer are facilitated via parallel connectors. This section explains the handshake of this interface. The data input circuit of this interface is shown in Fig. 2-2. Fig.
THEORY OF OPERATION Fig. 2-3 Timing Chart of Parallel Interface 2-1-2. Serial Interface (option) When the serial interface is used, an optional Serial Interface Board is required to be installed. The board will change the voltage level (RS-232C <-------> TTL) and the data transfer method (Serial <-------> parallel). Fig.
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THEORY OF OPERATION IC4 is a dual RS-232C driver/receiver which includes a capacitive voltage generator to supply RS-232C voltage levels from a single 5V supply. Data from the host computer is sent from RXD via IC4 and is input to the MPU. Serial data input to the MPU is converted into parallel data, and output to the main logic board.
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THEORY OF OPERATION DTR method XON/XOFF method ETX/ACK method Fig. 2-6 Data Input Timing Chart with Serial Interface – 17 –...
THEORY OF OPERATION 2-2. General Flow Chart A general flow chart of editing and printing operations is shown in Fig. 2-7. Fig. 2-7 General Flow Chart of Editing and Printing – 18 –...
THEORY OF OPERATION 2-2-1. Editing Data stored in the RAM is read out sequentially by the CPU and then edited according to a function code that has been specified in advance. This editing takes places until the CR or CR + LF code appears or the line buffer becomes full. 2-2-2.
THEORY OF OPERATION Fig. 2-9 Print Head Temperature Detection Circuit 2-2-4. Carriage Motor Driving Circuit This printer employs a stepping motor as the carriage motor. Unlike regular motors on the market, this stepping motor will not operate just by connecting it to a power source. The motor operates only when a drive pulse is fed to it, but even then, it turns only a certain angle.
THEORY OF OPERATION 2-2-5. Carriage Motor Speed Control Since the carriage motor is a stepping motor, the carriage can be stopped at a desired position by controlling acceleration and deceleration. The carriage can also move backward. The rotational speed of the carriage motor is set by the number of pulses per time unit. The character pitch (horizontal character size) in each print mode is determined by changing this rotational speed (or carriage transfer speed).
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THEORY OF OPERATION Fig. 2-13 Paper Feed Motor Driving Signals The utilization of voltage applied to the paper feed motor is described as follows. Mode Voltage Application Operation VH (+25.5V) Motor Drive Standby: VL (+5V) Holding Bias Voltage to the paper feed motor is changed by setting CPU port P31 to LOW or HIGH and by turning transistor TR6 and transistor array TA1 ON or OFF.
THEORY OF OPERATION 2-3. Reset Circuit The RESET signal initializes the circuit elements and prevents operation errors when the power is turned on. The RESET signal is output for approx. 34ms. when the power is turned on, or while the RESET ( INPUT-PRIME ) signal is being output from the host computer.
THEORY OF OPERATION 2-4. Reset by +5V Line Voltage Detection A voltage-detecting IC (IC2 in Fig. 2-14) detects momentary drops in voltage or unstable voltage supply (due to power failures, etc.) on the +5V line. If the voltage on the +5V line falls below 4.25V, the RESET signal appears at the output terminal of the voltage-detecting IC.
THEORY OF OPERATION Mechanism 4-1. Print Head Mechanism The print head consists of 9 needle wires and 9 print solenoids. The following explains how each needle wire operates during printing. When the print solenoid is energized, the clapper is attracted by the iron core and the needle wire is driven toward the platen.
THEORY OF OPERATION Fig. 2-18 Print Head Carrying Mechanism 4-3. Ink Ribbon Feed Mechanism The ink ribbon feed mechanism is linked to the print head carrying mechanism described previously so that the ink ribbon is wound up automatically while the carriage moves left or right. The ribbon feed mechanism is driven by torque from the carriage motor, and carriage movement allows the idler gear to rotate.
THEORY OF OPERATION 4-4. Paper Feed Mechanism The paper feed motor is a PM (Permanent Magnet) type, four-phase and 48-pole pulse motor. Minimum paper feed is set at 1/432 inch. There are two ways of feeding paper available with this printer: Friction method and Tractor method. You can select one of the two methods, using the release lever.
THEORY OF OPERATION 4-5. Detectors Home Position Detector A photo-interrupter is used in the home position detector, which is set at the left side of the frame unit. ON/OFF signals are generated according to the position of the shield plate mounted at the base of the carriage, and the printing position is determined by these signals.
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CHAPTER 3 ADJUSTMENTS This printer has undergone various adjustments so that it will achieve standard performance. In this chapter, a brief explanation is given of the methods of adjustments. Please check this explanation when making maintenance inspections or when replacing parts to correct malfunctions.
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ADJUSTMENTS Gap Adjustment Between Print Head and Platen 1-1. Measuring Gap Between Print Head and Platen Remove the upper case unit according to procedures described in Chapter 4. Set the adjustment lever [1] at step two. Remove the ribbon guide [2]. Insert a thickness gauge [3] between the print head [4] and the platen [5], and measure the gap.
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ADJUSTMENTS Adjustment of Timing at Belt Tension The timing belt tension should be set at from 18g to 21g. (The belt tension must be measured with the designated tension gauge [1] .) After the belt has been used for a long time, however, it may be difficult to maintain prescribed tension because of belt deterioration or wear.
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ADJUSTMENTS Adjustment of Home Position Detector Remove the printer cover. Loosen the screw [1]. Set the projection [3] of the home position detector [2] between the two lines stamped. Tighten the screw [1]. Fig. 3-7 Adjustment of Home Position Detector –...
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CHAPTER 4 PARTS REPLACEMENT This chapter explains disassembly and reassembly of the printer. Note the following precautions during disassembly and reassembly. Disconnect the printer from the wall outlet before servicing it. Assembly is the reverse of disassembly unless otherwise specified. After reassembly, coat the screw heads with locking sealant.
PARTS REPLACEMENT Upper Case Unit Turn off the power switch [1] Remove • Printer cover • Rear cover • Platen knob [2] • ROM cover [3] • Five tapping screws [4] Move the carriage unit [5] over the right so that it aligns with the cut-out of the upper case unit [6] .
PARTS REPLACEMENT Printer Mechanism Remove • Upper case unit according to the procedure de- scribed in item 1. • Five tapping screws [1] • Screw [2] • Cable holder [3] Lift up the tab of the cable holder, and slide it to the left for removal.
PARTS REPLACEMENT Fuse Board Unit Remove • Upper case unit according to the procedure de- scribed in item 1. • Connector [1] • Two tapping screws [2] • Tapping screw [3] (Except for HK) • Tapping screw [4] • Power switch [5] •...
PARTS REPLACEMENT Print Head Remove • Printer cover • Ink ribbon cartridge • Cable holder [1] • Two tapping screws [2] • Head cable [3] • Print head [4] WARNING: The print head become hot after print- ing so wait for it to cool before remov- ing it.
PARTS REPLACEMENT Carriage Motor Unit Remove • Printer mechanism according to the procedure described in item 3. • Cord fastener binding the lead wires. • Connector [1] • Two screws [2] • Carriage motor unit [3] Adjust • Timing belt tension Refer to item 2 of Chapter 3.
PARTS REPLACEMENT 11. Platen Unit Remove • Upper case unit according to the procedure de- scribed in item 1. Move the bail lever [1] forward. Remove • Two nuts [2] • Tractor stay [3] • Ground contact spring [4] • Platen holder R [5] •...
MAINTENANCE AND LUBRICATION Maintenance In order to maintain the optimum performance of this printer and to prevent trouble, maintenance must be carried out according to the following items. 1-1. Cleaning Removal of dirt Wipe off dirt with a soft cloth soaked in alcohol or benzine. *Note: Do not use thinner, trichlene or ketone solvents because they may damage plastic parts.
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MAINTENANCE AND LUBRICATION Lubrication Lubrication is very important to maintain optimum performance and to prevent trouble. 2-1. Lubricant The type of lubricant greatly affects the performance and durability of the printer, especially in a low temperature environment. We recommend use of the grease and lubrication oils listed below for this printer. Product name Maker FLOIL GB-TS-0...
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MAINTENANCE AND LUBRICATION Fig. 5-1 Lubricated Areas 1 – 47 –...
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MAINTENANCE AND LUBRICATION Fig. 5-2 Lubricated Areas 2 – 48 –...
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CHAPTER 6 TROUBLESHOOTING Troubleshooting Procedures ................Unit Replacement Flow Chart ................Repair by Unit Replacement ................Repair by Replacement of Parts ................ 4-1. Does not Operate at All with Power on ............... 59 4-2. Power Supply Circuit Abnormal ................60 4-3.
TROUBLESHOOTING Troubleshooting Procedures Troubleshooting is never easy because various problems arise depending upon the particular location of the breakdown, but the following procedures should be adhered to in making repairs. At the first stage, conduct repairs through unit replacements. The two display codes appearing in the flow chart are defined as follows: 1) indicates main logic board replacement and 2) indicates printer mechanism replacement, to be carried out if the problem has not been corrected.
TROUBLESHOOTING Unit Replacement Flow Chart Unit Exchange Sequence Problem Category Remarks Power Main Printer Control Details supply unit logic board mechanism panel board Specific display lamp only will not glow Specific switch only cannot be input Buzzer does not sound (sound volume inadequate) Strange sounds...
TROUBLESHOOTING Repair by Unit Replacement START * Turn power off. * Remove I/F cable. * Mount ink ribbon. * Set paper. * Move carriage to center. Turn power on. Carriage Movement? Carriage operates normally? Carriage motor operating waveform is normal? *1 1) Replace main logic board.
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TROUBLESHOOTING On line lamps light? On line lamp signal is normal? Replace main logic board. On line switch in on. (Take Off Line) Replace control panel board. On line lamp is out? Paper feed switch is on. Paper feed switch operation is normal? Paper feed motor drive waveform...
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TROUBLESHOOTING Printing operation is normal? Print head drive signal waveform is normal? *3 1) Replace main logic board. 2) Replace printer mechanism. Replace printer mechanism. Paper feed operation is normal? Paper feed motor drive waveform is normal? *2 1) Replace main logic board. Ribbon feed 2) Replace printer mechanism.
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TROUBLESHOOTING Printing begins? Printing operation normal? 1) Replace I/F cable. Printer is normal; host 2) Replace main logic board. computer print program stops. 3) Check host computer. Works with carriage hand? Replace printer mechanism. Output (VH, VL, +5V) of power supply unit is normal? *4 1) Replace main logic board.
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TROUBLESHOOTING Output of power supply unit is normal? *4 Power source is off. Replace power supply unit. Connect connector CN201 of main logic board. Power source is on. Fuse blows out? Replace fuse 1) Replace main logic board. 2) Replace printer mechanism. 3) Replace control panel board.
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TROUBLESHOOTING I/F signal is normal? *5 Ready condition? There is data transmission? Hardware check or check I/F mode set of host computer print up properly? program. 1) Replace I/F cable. 2) Replace main logic board. I/F mode set up changed. On line switch goes ON/OFF? On line lamp...
TROUBLESHOOTING Repair by Replacement of Parts 4-1. Does not Operate at All with Power on START VH, VL, +5V supplied? *4 See 4-2. Power Supply DC Power abnormal. Circuit Abnormal. RESET signal becomes HIGH? *6 Check RESET circuit; replace parts. Crystal waveform is normal? *7...
TROUBLESHOOTING 4-2. Power Supply Circuit Abnormal Remove connectors CN201 of the main logic board. START Fuse F1 is blown? Replace Fuse F1 Fuse is blown again? Replace Transformer. ACS1 and ACS2 are supplied? Connect the The no load voltages are below: connector CN201.
TROUBLESHOOTING 4-3. Defective Motor Operation START START LF-CMN CR-CMN signal is normal? signal is normal? Check or replace Check or replace 1) TA1 1) TA1 2) TR6 2) TR5 or TR1 3) CPU 3) CPU LF-ø1, CR-ø1, ø2, ø3, ø4 are ø2, ø3, ø4 are normal? *2 normal? *1...
TROUBLESHOOTING 4-4. Defective Print Head Operation START Does not print at all? A specific pin does not VH(+25.5V) work? line is supplied? Check or replace 1) TR8 ~ TR16 Power supply unit abnormal. (Refer to item 4-2.) Check or replace Print is light 1) TR1 as whole?
TROUBLESHOOTING 4-5. Defective Interface Operation START Set at on line Start print program of host computer. Is I/F signal normal? *5 Incorrect print generated? Check I/F cable. Check or replace 1) IC3 2) Gate array 3) CPU Check operation – 63 –...
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CHAPTER 7 PARTS LIST HOW TO USE PARTS LIST DRWG. NO. This column shows the drawing number of the illustration. REVISED EDITION MARK This column shows a revision number. Parts that have been added in the revised edition are indicated with “#”. Parts that have been abolished in the revised edition are indicated with “*”.
Printer Assembly DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 89064810 MECHANISM WITH HEAD DP935 82900772 RIBBON HOLDER TO SECTION 2-2 87291130 LOWER CASE UNIT NX-1500 EXCEPT FOR SC 87291150 LOWER CASE UNIT LC-15 SC FOR SC – 66 –...
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PARTS NAME Q'TY REMARKS RANK 87292150 MAIN LOGIC BOARD UNIT NX-1500 US,UK,AS,TW,LA 87292160 MAIN LOGIC BD UNIT NX-1500 HK FOR HK 87292170 MAIN LOGIC BD UNIT LC-15 EC FOR EC,SC 87292170 MAIN LOGIC BD UNIT LC-15 EC FOR SU 87295900...
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DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 01914031 SCREW TAT 4-12 PT-FL 01914030 SCREW TAT 4-15 PT 87299160 PULL TRACTOR UNIT PT-15XJ FOR US,LA :OPTION 87299190 PULL TRACTOR UNIT PT-15XJ EXC.FOR US,LA:OPTION 89590183 ASF SF-15DJ FOR US,LA :OPTION 89590181 ASF SF-15DJ FOR EC...
2-2. Parts List Printer Mechanism DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 89131010 PRINT HEAD DP9305 87060130 FRAME UNIT 87060131 FRAME UNIT NOTE1 87061110 CARRIAGE MOTOR UNIT 87067170 BAIL ROLLER SHAFT UNIT 83400650 BAIL LEVER L 83400470 RELEASE LEVER 83400471 RELEASE LEVER 83400670...
3-1. Upper Case Unit DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 80086550 OPERATION SHEET SPECIAL LC-15 FOR SU 80087200 OPERATION SHEET NX-1500 SU FOR SU 80086220 OPERATION SHEET NX-1500 EXCEPT FOR SU 80081910 BRAND SEAL NX-1500 FOR NX-1500 80081911 BRAND SEAL...
3-2. Lower Case Unit DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 83023410 LOWER CASE NX-1500 83023411 LOWER CASE NX-1500 83023413 LOWER CASE NX-1500 82010900 BOARD CHASSIS NX-1500 82010910 POWER CHASSIS NX-1500 82501050 GROUND SPRING NX-1500 82901390 GROUND BRACKET...
83023450 INTERFACE COVER NX-1500 83024920 INTERFACE COVER ZB-15 83024921 INTERFACE COVER ZB-15 16-2 87297030 PARALLEL IF BOARD UNIT NX-1500 87299260 SERIAL I/F BOARD UNIT EXCEPT FOR HK:OPTION 87299270 SERIAL I/F BOARD UNIT X15 HK FOR HK :OPTION 16-3 01903064 SCREW TAT 3-5 CT...
3-4. Pull Tractor Unit (option) DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 22- 1 87299340 FRAME R UNIT PT-15X 22- 2 87299350 FRAME L UNIT PT-15X 22- 3 83023560 TRACTOR COVER R PT-15X 22- 4 83023570 TRACTOR COVER L PT-15X 22- 5 83200090...
3-7. Platen Unit DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 10-1 80202140 PLATEN B 10-1 80202141 PLATEN B 10-2 83100550 PLATEN GEAR A 10-3 83100560 PLATEN GEAR B 10-4 83902310 PLATEN HOLDER 10-5 80530520 PLATEN GEAR SPRING 10-6 04020014 STOP RING SE6.0 04020022...
5-3. Parts List Main Logic Board DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 08210052 TTL IC 74LS374P 08200109 IC-RESET M51953BL 08210017 TTL IC 74LS05 08240020 GATE ARRAY MB623153U-XL 08222026 EPROM 27256-150NS XL15.**.C :EXC. SU,PL 08222026 EPROM 27256-150NS XL15.**.SUCG :FOR SU 08222026 EPROM 27256-150NS...
6-2. Component Layout 6-3. Parts List Control Panel Board DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK R1-2 06042715 RD RESISTOR 270 OHM 1/4W NOT MOUNTED R4-11 06042715 RD RESISTOR 270 OHM 1/4W LED1 08300055 LED LT-1H11A LED2 08300058 LED LT-1E21A LED3 NOT MOUNTED...
Fuse Board 7-1. Circuit Diagram 7-2. Component Layout 7-3. Parts List DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 05291042 FILM CAPA. 0.1UF 250V C2-3 05192224 CERA. CAPA. 2200PF 400V EXCEPT FOR HK,SU NOT MOUNTED :HK,SU 09251106 LINE FILTER SU10V-05050 09990058 FUSE 5TT1A 250V FOR US,TW...
9-3. Parts List Serial Buffer Board DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 08220102 HD63A03YF 08250011 MASKED CPU HD63B01YF-IF IC6 IS NOT MOUNTED NOT MOUNTED 08210112 TTL IC 74LS00 (FLAT TYPE) 08200126 IC-I/F LT1081CS 08200127 IC-I/F MC34051M 08220090 EPROM 2764-200NS X.**.OPB...
10-3. Parts List Parallel Buffer Board DRWG.NO. REV. PARTS NO. PARTS NAME Q'TY REMARKS RANK 08250011 MASKED CPU HD63B01YF-IF NOT MOUNTED 08221033 PSRAM TC518128AFL-80 08210113 TTL IC 74LS05 (FLAT TYPE) IC5-6 08210112 TTL IC 74LS00 (FLAT TYPE) 08210114 TTL IC 74LS112 (FLAT TYPE) NOT MOUNTED NOT MOUNTED 06751021...
11. Waveform with Oscilloscope (1) Crystal (10 MHz) (2) RESET (Power on reset) Crystal Pin 33 of IC9 Upper : RESET input Pin 4 of IC2 Time/Div : 0.2 µs Lower : RESET output Pin 5 of IC2 Volt/Div : 1V Time/Div : 10 ms Volt/Div : 2V...
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(7) Carriage Motor Control Signal and Driving Signal (8) Paper Feed Motor Common Control Signal and Driving Signal Upper : Carriage-ø1 Control Signal Pin 13 of IC9 Upper : LF-CMN Control Signal Pin 22 of IC9 Lower : Carriage-ø1 Driving Signal Pin 3 of CN5 Lower : LF-CMN Driving Signal Pin 1 of CN6 Time/Div : 1 ms...
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HEAD QUARTERS OVERSEAS SUBSIDIARY COMPANIES STAR MICRONICS DEUTSCHLAND GMBH STAR MICRONICS U.K.LTD. STAR MICRONICS CO., LTD. JAPAN STAR MICRONICS AMERICA INC. Westerbachstraße 59 P.O.Box 940330 Star House, Peregrine Business D-60489 Frankfurt/Main 90 Park, Gomm Road, High Wycombe 536 Nanatsushinya, Shimizu, 70-D Ethel Road West.