Epson 670 1.3.2 Interface Specification

LQ-670 Service Manual

Rev. A

1-1

8

1.3.2 Interface Specification

This printer provides bi-directional 8-bit parallel interface and Type-B optional interface slot as standard.

1.3.2.1 Parallel interface (Forward channel)

[Transmission mode] : 8 bit parallel, IEEE-1284 compatibility mode

[Adaptable connector] : 57-30360 (Amphenol) or equivalent

[Synchronization] : /STROBE pulse

[Handshaking] : BUSY and /ACKNLG signals

[Signal level] : TTL compatible (IEEE-1284 level 1 device)

Pin No. Signal Name Return

GND

Pin

In/Out * Function description

1 /STROBE 19 In Stroke pulse. Input data is latched at falling edge of

the signal.

2∼9DATA1∼820∼27 In Each signal represents information of parallel data

from 1 bit to 8 bit. The data is 1 at “HIGH” and is 0

at “LOW”.

10 /ACKNLG 28 Out This signal (negative pulse) indicates that the printer

has received data and is ready to accept next one.

The pulse width is 5µs.

11 BUSY 29 Out This s ignal’s “HIGH” level indicates that the printer

is not ready to accept data. On the other hand,

“LOW” means the printer can take data.

(Refer to the next page for conditions when this

signal becomes high level)

12 PE 28 Out This signal’s “HIGH” level indicates that the printer

is in a state of paper-out error.(Refer to the next

page for the condition when this signal becomes

high level.)

13 SLCT 28 Out Always at high level when the printer is powered on.

14 /AFXT 30 In Not used.

31 /INIT 30 In This signal’s negative pulse initializes printer.

32 /ERROR 29 Out This signal’s low level means the printer is in a state

of error. (Refer to the next page for conditions when

the signal becomes low level)

36 /SLIN 30 In Not used.

18 Logic H ---- Out This line is pulled up to +5V through 3.9 kΩ resistor.

35 +5V --- Out This line is pulled up to +5V through 1.0 kΩ resistor.

17 Chassis --- --- Chassis GND.

16,33

19-30 GND --- --- Signal GND.

15,34 NC --- --- Not connected.

Note)

*In/Out shows the direction of signal flow from the printer's point of view.

Note)

If the signal is “LOW” and active state, the signal is marked with “/”.

Table 1-19. Connector Pin Assignment and Signals

Contents

Main NOTICE Copyright 1997 by SEIKO EPSON CORPORATION Nagano, Japan PRECAUTIONS WARNING CAUTION WARNING CAUTION PREFACE Page Page Chapter 1 Product Descriptions 1.1 Specifications 1.1.1 Features Page 1.2 Hardware Specifications 1.2.1 Printing Method 1.2.2 Printing Specifications Rev. A 1- 1.2.3 Paper Handling Specifications 1.2.4 Paper Specification Rev. A 1- Note1) Note3): Note2): Note2): Page Page 1.2.5 Printable Area Rev. A 1-11 Note *1) Printable Area Printable Area BM 1.2.6 Ribbon Cartridge 1.2.7 Input data buffer Note*) 1.2.8 Electrical Specification 1.2.9 Reliability 1.2.10 Environmental Condition 1.2.11 Safety Approvals 1.2.12 CE Marking 1.2.13 Acoustic Noise 1.3 Firmware Specification 1.3.1 Control Codes and Fonts Page 1.3.2 Interface Specification 1.3.2.1 Parallel interface (Forward channel) Page 1.3.2.2 Parallel Interface (Reverse channel) Note*): Rev. A 1-21 1.3.2.3 Optional Interface 1.3.2.4 Interface Selection 1.3.3 Prevention Hosts from Data Transfer Timeout 1.4 Operation 1.4.1 Control Panel 1.4.1.1 Usual Operation Page 1.4.1.2 Switches 1.4.1.3 Indicators(LED) 1.4.1.4 Buzzer 1.4.2 Default Setting Notes. 1.4.3 Bi-d Adjustment 1.4.4 Initialization 1.4.5 Errors 1-3 1.5 Main Components 1.5.1 C214 Main Board 1.5.2 C214PSB Board Page Chapter 2 Operating Principles Rev. A 2-1 2.1 Printer Mechanism Operation 2.1.1 Printing Mechanism Page 2.1.2 Carriage Mechanism Page 2.1.3 Ribbon Advance Mechanism 2- 2.1.4 Paper Advance Mechanism 2.1.4.1 Paper Advance Mechanism 2.1.4.2 Paper Advance Detector Mechanism Page 2.1.4.3 Release Lever Mechanism Release Lever Tractor Gear Roller, PF Drive Tractor Transmission Gear 2.1.5 Platen Gap Adjustment Rev. A 2-11 2.2 Power Supply Operation 2.2.1 Power Supply Circuit 2.2.1.1 Power Supply Overview 2.2.1.2 Power Supply Circuit Operation Rev. A 2-1 2.2.2 Control Circuit 2.2.2.1 Operating Principles of the Control Circuit 2.2.2.2 EEPROM Control Circuit 2.2.2.3 System Reset Circuit 2.2.2.4 Power Off Detector Circuit 2.2.2.5 Print Head Driver Circuit 2.2.2.6 CR Motor Driver Circuit 2.2.2.7 PF Motor Driver Circuit 2.2.2.8 Operation Panel Control Circuit Page Chapter 3 Disassembly and Assembly Page 3.1 Overview 3.1.1 Precautions for Disassembling the Printer 3.1.2 Tools WARNING 3-2 3.1.3 Service Check After Repair 3.1.4 Specifications for Screws 3-4 3.2 Printer Disassembly and Assembly Figure 3-1. Disassembly Flowchart The flowchart below show you the basic order for disassembly. Before disassembling any part of the printer, note the warnings in Section 3.1.1. START 3.2.1 HOUSING, UPPER Removal 3-6 3.2.2 Printer Mechanism Removal 3.2.3 C214 MAIN Board Removal 3.2.4 C214 PSB/PSE Board Removal 3.2.5 EP-ROM Replacement CHECK POINT 3.2.6 Printhead Removal 3.2.7 Ribbon Mask Removal 3.2.8 PAPER EXIT ASSY. Removal 3.2.9 Ribbon Mask Holder Removal 3.2.10 PW Detector (Top) Removal 3.2.11 MOTOR, CR Removal 3.2.12 Carriage Assy. Removal CHECK POINT Page 3.2.12.1 RATCHET, RD Removal 3.2.13 PAPER GUIDE Removal Page Chapter 3 Disassembly and Assembly Rev. A 3-21 3-22 3.2.14 Platen Removal 3.2.15 MOTOR, PF Removal Page 3.2.19 DETECTOR, PE, FRONT Removal 3.2.20 DETECTOR, PE, REAR Removal 3.2.21 LEVER, RELEASE Removal 3.2.22 Tractor ASSY. Removal Page Rev. A 4-1 4.1 Adjustment Overview Note*2) Note*1) 4.1.1 Required Adjustments 4.1.2 Required Adjustment Tools 4.2 Adjusting and Resetting the Printer Do not rotate the platen roller during this adjustment. 4.2.1 Platen Gap Adjustment Rev. A 4- 4.2.2 Factory Setting Page Rev. A 4- 4.2.3 Bi-d Adjustment Page Page 5.1 Overview 5- 5.2 Unit Level Troubleshooting Page Page Page Page Rev. A 5- Page View A R F R L 1-24 :Wire Number C :Common Terminal T:Thermistor Terminal Note*) Rev. A 5-11 5.3 Repairing the Power Supply Circuit Board Page Page 5.4 Repairing the Main Board Page Page 5.5 Repairing the Printer Mechanism Page Page 6.1 Preventive Maintenance Page Appendix A.1 Connector Summary A- Rev. A A- A- Page Page Page Page Page Page Page Page Page A-1 Page A.5 Dimension and Weight EPSON OVERSEAS MARKETING LOCATIONS As of September, 1996