Epson TM-T20II-i Use and care manual

Technical Reference Guide
Describes features of the product.
Describes advanced usage methods for the product.
Describes precautions for replacement.
Describes how to handle the product.
Describes setup and installation of the product and
peripherals.
Describes how to control the printer and necessary
information when you develop applications.
Describes general specications and character code tables.
M00122200
Rev. A
Product Overview
Setup
Application Development Information
Handling
Appendix
Advanced Usage
Replacement of the TM-T20II

Cautions
•No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by
any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written
permission of Seiko Epson Corporation.
•The contents of this document are subject to change without notice. Please contact us for the latest
information.
•While every precaution has been taken in the preparation of this document, Seiko Epson Corporation
assumes no responsibility for errors or omissions.
•Neither is any liability assumed for damages resulting from the use of the information contained herein.
•Neither Seiko Epson Corporation nor its affiliates shall be liable to the purchaser of this product or third
parties for damages, losses, costs, or expenses incurred by the purchaser or third parties as a result of:
accident, misuse, or abuse of this product or unauthorized modifications, repairs, or alterations to this
product, or (excluding the U.S.) failure to strictly comply with Seiko Epson Corporation's operating and
maintenance instructions.
•Seiko Epson Corporation shall not be liable against any damages or problems arising from the use of any
options or any consumable products other than those designated as Original Epson Products or Epson
Approved Products by Seiko Epson Corporation.
Trademarks
EPSON is a registered trademark of Seiko Epson Corporation. Exceed Your Vision and ESC/POS are registered
trademarks or trademarks of Seiko Epson Corporation.
Microsoft and Windows are registered trademarks of Microsoft Corporation in the United States and/or other
countries.
Wi-Fi®, WPATM, and WPA2TM are either registered trademarks or trademarks of Wi-Fi Alliance®.
IOS is a trademark or registered trademark of Cisco in the U.S. and other countries and is used under license.
Android and Google Play are trademarks of Google, Inc.
All other trademarks are the property of their respective owners and used for identification purpose only.
ESC/POS®Command System
EPSON ESC/POS is a proprietary POS printer command system that includes patented or patent-pending
commands. ESC/POS is compatible with most EPSON POS printers and displays. ESC/POS is designed to
reduce the processing load on the host computer in POS environments. It comprises a set of highly functional
and efficient commands and also offers the flexibility to easily make future upgrades.
©Seiko Epson Corporation 2019. All rights reserved.

3
For Safety
Key to Symbols
The symbols in this manual are identified by their level of importance, as defined below. Read the following
carefully before handling the product.
Warnings
WARNING
You must follow warnings carefully to avoid serious bodily injury.
CAUTION
Provides information that must be observed to prevent damage to the equipment or loss of data.
•Possibility of sustaining physical injuries.
•Possibility of causing physical damage.
•Possibility of causing information loss.
Provides information that must be observed to avoid damage to your equipment or a malfunction.
Provides important information and useful tips.
WARNING
•To avoid risk of electric shock, do not set up this product or handle cables during a
thunderstorm
•Never insert or disconnect the power plug with wet hands.
Doing so may result in severe shock.
•Handle the power cable with care.
Improper handling may lead to fire or electric shock.
∗Do not modify or attempt to repair the cable.
∗Do not place any heavy object on top of the cable.
∗Avoid excessive bending, twisting, and pulling.
∗Do not place the cable near heating equipment.
∗Check that the plug is clean before plugging it in.
∗Be sure to push the plug all the way in.
•Be sure to use the specified AC adapter.
Connection to an improper power source may cause fire or shock.
•Do not place multiple loads on the power outlet.
Overloading the outlet may lead to fire.
•Shut down your equipment immediately if it produces smoke, a strange odor, or unusual noise.
Continued use may lead to fire. Immediately unplug the equipment and contact qualified
service personnel.
•Never attempt to repair this product yourself. Improper repair work can be dangerous.
•Never disassemble or modify this product.
Tampering with this product may result in injury or fire.
•Do not allow foreign matter to fall into the equipment.
Penetration by foreign objects may lead to fire.

4
Cautions
Caution Labels
The caution labels on the product indicate the following precautions.
CAUTION:
Do not touch the thermal head and the frame on its side during or immediately after use. After printing, the thermal head
and its surroundings can be very hot.
Restriction of Use
When this product is used for applications requiring high reliability/safety, such as transportation devices
related to aviation, rail, marine, automotive, etc.; disaster prevention devices; various safety devices, etc.; or
functional/precision devices, etc., you should use this product only after giving consideration to including fail-
safes and redundancies into your design to maintain safety and total system reliability.
Because this product was not intended for use in applications requiring extremely high reliability/safety, such as
aerospace equipment, main communication equipment, nuclear power control equipment, or medical
equipment related to direct medical care, etc., please make your own judgment on this product's suitability after
a full evaluation.
WARNING
•If water or other liquid spills into this equipment, do not continue to use it.
Continued use may lead to fire. Unplug the power cord immediately and contact qualified
service personnel.
•Do not use aerosol sprayers containing flammable gas inside or around this product.
Doing so may cause fire.
CAUTION
•Do not connect cables in ways other than those mentioned in this manual.
Different connections may cause equipment damage or fire.
•Be sure to set this equipment on a firm, stable, horizontal surface.
The product may break or cause injury if it falls.
•Do not use this product in locations subject to high humidity or dust levels.
Excessive humidity and dust may cause equipment damage or fire.
•Do not place heavy objects on top of this product. Never stand or lean on this product.
Equipment may fall or collapse, causing breakage and possible injury.
•Take care not to push your hand or finger against the manual cutter. Doing so may injure your
hand or finger.
∗When you remove printed paper
∗When you perform other operations such as loading/replacing roll paper
•Do not open the roll paper cover without taking the necessary precautions, as this can result in
injury from the autocutter fixed blade.
•To ensure safety, unplug this product before leaving it unused for an extended period.
•Do not remove the user interface board installed on this product.

5
Note About Interference
•This product generates, uses, and can radiate radio frequency energy and, if not installed and used in
accordance with the instruction manual, may cause harmful interference to radio communications.
•If this equipment does cause harmful interference to radio or television reception, which can be determined
by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more
of the following measures:
- Reorient or relocate the receiving antenna for the radio/TV.
- Increase the separation between the equipment and the radio/TV.
- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
- Consult your dealer or an experienced radio/TV technician for help.
•Never disassemble or modify this product.
•Seiko Epson Corporation shall not be liable for interference to radio/TV resulting from changes or
modifications to this product not expressly approved by Seiko Epson Corporation.
Open Source Software License
This product uses open source software in addition to Epson proprietary software. For information of the open
source software used in this product, see the following URL.
http://xxx.xxx.xxx.xxx/licenses.html
For “xxx.xxx.xxx.xxx” in the above URL, input your printer’s IP address.

6
About this Manual
Aim of the Manual
This manual provides developers/engineers with all the necessary information for design, development and
installation of a POS system, and also design and development of a printer application.
Manual Content
The manual is made up of the following sections:
Chapter 1 Product Overview
Chapter 2 Setup
Chapter 3 Advanced Usage
Chapter 4 Application Development Information
Chapter 5 Handling
Chapter 6 Replacement of the TM-T20II
Appendix Product Specifications
Specifications of Interfaces and Connectors

7
Contents
■For Safety.................................................................................................................................3
Key to Symbols.................................................................................................................................................................. 3
Warnings ............................................................................................................................................................................. 3
Cautions............................................................................................................................................................................... 4
■Caution Labels........................................................................................................................4
■Restriction of Use...................................................................................................................4
■Note About Interference ......................................................................................................5
Open Source Software License ................................................................................................................................... 5
■About this Manual .................................................................................................................6
Aim of the Manual ........................................................................................................................................................... 6
Manual Content................................................................................................................................................................ 6
■Contents ..................................................................................................................................7
Product Overview .......................................................................................... 11
■Features ................................................................................................................................ 11
■Product Configurations ..................................................................................................... 12
Models................................................................................................................................................................................12
Accessories .......................................................................................................................................................................12
■Parts and Functions............................................................................................................ 13
LED lights ..........................................................................................................................................................................14
Connectors .......................................................................................................................................................................15
■Status and Errors................................................................................................................. 16
Online and Offline..........................................................................................................................................................16
Automatically Recoverable Errors ............................................................................................................................16
Recoverable Errors .........................................................................................................................................................17
Unrecoverable Errors ....................................................................................................................................................17
Status Display ..................................................................................................................................................................18
■NV Memory .......................................................................................................................... 19
NV Graphics Memory....................................................................................................................................................19
User NV Memory ............................................................................................................................................................19
Memory Switches (Customized Value)...................................................................................................................19
R/E (Receipt Enhancement)........................................................................................................................................19
User-defined Page .........................................................................................................................................................20
Maintenance Counter...................................................................................................................................................20
■Simple Setup for Wireless LAN ......................................................................................... 21
■Useful Functions for Smart Devices ................................................................................ 22
QR Code.............................................................................................................................................................................22

8
Setup ............................................................................................................... 23
■Flow of Setup....................................................................................................................... 23
■Installing the Printer ..........................................................................................................24
Installing the Printer Vertically ..................................................................................................................................24
Hanging the Printer on a Wall....................................................................................................................................25
■Adjusting the Roll Paper Near-End Sensor .................................................................... 27
■Connecting the AC adapter .............................................................................................. 28
Connecting Procedure .................................................................................................................................................28
■Connecting the Printer to the Host ................................................................................. 29
USB Interface ...................................................................................................................................................................29
Serial Interface ................................................................................................................................................................29
Ethernet Interface ..........................................................................................................................................................30
Wireless LAN Interface (when OT-WL06 is used) ................................................................................................30
■Connecting the Cash Drawer............................................................................................ 34
Cash Drawer Requirements........................................................................................................................................34
Connecting the Drawer Kick Cable..........................................................................................................................35
■Connecting the Optional External Buzzer ..................................................................... 36
Connecting Procedure .................................................................................................................................................36
■Connecting the Optional Wireless LAN Unit.................................................................. 38
■Attaching the Power Switch Cover .................................................................................. 39
■Changing the Paper Width................................................................................................ 40
Advanced Usage ............................................................................................ 41
■Software Settings ...............................................................................................................41
Feature ...............................................................................................................................................................................42
■Setting/Checking Modes................................................................................................... 50
Self-test Mode .................................................................................................................................................................52
NV Graphics Information Print Mode......................................................................................................................52
Receipt Enhancement Information Print Mode ..................................................................................................53
Software Setting Mode ................................................................................................................................................53
Restore Default Values Mode.....................................................................................................................................55
Interface Setup Mode...................................................................................................................................................56
Peripheral Device Information Print Mode...........................................................................................................57
Hexadecimal Dumping Mode ...................................................................................................................................58
■Printing a Status Sheet ...................................................................................................... 59
■Resetting the Interface Settings ...................................................................................... 61

9
Application Development Information....................................................... 62
■Controlling the Printer....................................................................................................... 62
ePOS-Print XML...............................................................................................................................................................62
ESC/POS.............................................................................................................................................................................62
■Controlling the Cash Drawer ............................................................................................ 63
■Controlling the Optional External Buzzer ...................................................................... 64
■Software ............................................................................................................................... 65
Development Kits ..........................................................................................................................................................65
Drivers ................................................................................................................................................................................66
Utilities ...............................................................................................................................................................................67
Others.................................................................................................................................................................................67
Download .........................................................................................................................................................................67
Handling ......................................................................................................... 68
■Installing and Replacing Roll Paper ................................................................................ 68
■Removing Jammed Paper ................................................................................................. 70
When the Roll Paper Cover Cannot be Opened..................................................................................................70
■Cleaning the Printer ........................................................................................................... 72
Cleaning the Printer Case............................................................................................................................................72
Cleaning the Thermal Head/Platen Roller.............................................................................................................72
■Preparing for Transport ..................................................................................................... 73
Replacement of the TM-T20II........................................................................ 74
■Compatibility....................................................................................................................... 74
Printing ..............................................................................................................................................................................74
Print Speed .......................................................................................................................................................................74
Logo Registration...........................................................................................................................................................74
Driver Compatibility......................................................................................................................................................74
Overall Dimensions .......................................................................................................................................................75
Appendix......................................................................................................... 76
■Product Specifications ....................................................................................................... 76
Printing Specifications .................................................................................................................................................77
Character Specifications ..............................................................................................................................................78
Paper Specifications ......................................................................................................................................................79
Printable Area..................................................................................................................................................................80
Printing and Cutting Positions ..................................................................................................................................82
Electrical Characteristics..............................................................................................................................................83

10
Environmental Conditions..........................................................................................................................................84
External Dimensions and Mass .................................................................................................................................85
■Specifications of Interfaces and Connectors................................................................. 86
USB Interface ...................................................................................................................................................................86
RS-232 Serial Interface .................................................................................................................................................87
Ethernet Interface ..........................................................................................................................................................90
Wireless LAN Interface (when OT-WL06 is used) ................................................................................................92

11
Chapter 1 Product Overview
Product Overview
This chapter describes features of the product.
Features
Printing
•High speed receipt printing is possible (250 mm/s {9.84"/s} maximum).
•Switching from 80 mm {3.15"} width paper printing to 58 mm {2.28"} width paper printing is available.
Handling
Easy drop-in paper loading
Software
•Command protocol is based on the ESC/POS®Proprietary Command System.
•Windows printer drivers, OPOS ADK, and OPOS ADK for .NET are available.
•Printing of various types of bar codes, GS1-DataBar, and two-dimensional symbols (PDF417, QR code,
MaxiCode, Composite Symbology, Aztec Code, DataMatrix) is supported.
•A maintenance counter function is supported.
•Multiple languages are supported for code pages, Windows drivers, and utility software.
Interface
The interface is selectable when purchasing the product.
Environment
Paper reduction function is available.
Others
•Various installation layouts (horizontal, vertical, and wall-hanging installation) are selectable.
•Optional Wireless LAN unit and external buzzer are available.

12
Chapter 1 Product Overview
Product Configurations
Models
•Serial (RS-232C)/USB interface model
•Ethernet interface model
Accessories
Included
•Roll paper (for operation check)
•Power switch cover
•Soft power switch cover
•Wall hanging bracket
•Rubber feet for vertical installation
•58 mm width roll paper guide
•AC adapter
•Interface cable*
•AC cable*
•User's Guide
*: Not included with some models
Options
•Affixing tape for fixing the printer (Model: DF-10)
•External buzzer (Model: OT-BZ20)
•Wireless LAN cable set (Model: OT-WL06)

13
Chapter 1 Product Overview
Parts and Functions
1 Roll paper cover Open this cover to install/replace the roll paper.
2 Manual cutter Use this cutter when you cut the roll paper manually.
3 Cutter cover If the roll paper cover will not open due to a paper jam, open this cover and unlock the
autocutter blade.
4 Power switch Press this button to turn the printer on or off. ( : OFF/ : ON)
5 Power switch cover Put this cover on the power switch to prevent it being operated inadvertently.
To operate the power switch, insert an object with a pointed tip such as a ballpoint
pen into the hole on the power switch cover.
For attaching the power switch cover, see "Attaching the Power Switch Cover" on
page 39.
6Status sheet button
(Ethernet interface model
only)
Press this button to print the interface status sheet, or to reset the interface settings.
7 Cover open lever Use this button to open the roll paper cover.
8 Feed button Press this button to feed the roll paper by one line. Hold down this button to feed the
roll paper continuously.
9 LED lights For details on the LED lights, see "LED lights" on page 14.

14
Chapter 1 Product Overview
LED lights
1Power LED •On when the power supply is on.
•Off when the power supply is off.
2Error LED Lights or flashes when the printer is offline. (For information about the lighting and
flashing patterns, see "Status and Errors" on page 16.)
•Lights after the power is turned on or after a reset (offline). Automatically goes out
after a while to indicate that the printer is ready.
•Lights when the end of the roll paper is detected, and when printing has stopped
(offline). If this happens, replace the roll paper.
•Off when the printer is in standard mode (online).
3Paper LED •Lights when there is no more roll paper. If the near-end detection is set to
“Enabled”, this LED also lights when the near-end of the paper is detected.
•Off when there is a sufficient amount of roll paper remaining.
•Flashes when a self-test is in progress or when macro execution standby state.
1
2
3

15
Chapter 1 Product Overview
Connectors
All connectors are located on the lower rear of the printer.
•The interface installed differs according to the model.
•Do not remove the user interface board installed on this product.
1 Serial interface Connects the serial cable for connecting to a computer.
2 USB (Type-B) connector Connects the USB cable for connecting to a computer.
The connector is covered with a plate when shipped with some model.
When using this connector with such model, set Interface Selection in the
printer's Software Setting Mode to [Built-in USB]. See "Software Settings"
on page 41.
3Ethernet connector Connects the 10BASE-T/100BASE-TX Ethernet cable.
4 Power supply connector Connects the AC cable. "Connecting the AC adapter" on page 28
5 USB (Type-A) connector Use only for connecting optional Wireless LAN unit.
Leave the cover in place if this connector is not used.
6 Drawer kick connector Connects the cash drawer or the optional external buzzer.
"Connecting the Cash Drawer" on page 34
"Connecting the Optional External Buzzer" on page 36

16
Chapter 1 Product Overview
Status and Errors
The LEDs light or flash to indicate the printer status.
Online and Offline
Online
The printer is online and ready for normal printing unless there is a reason to go offline.
Offline
The printer automatically goes offline under the following conditions:
•While the printer power is turning on/off
•While a self-test is running
•While roll paper is fed using the Feed button
•When the printer stops printing due to a paper end
(When the paper end is detected by the roll paper end sensor)
•During an operation standby state
•When an error has occurred ("Status and Errors" on page 16)
•While the roll paper cover is open
Automatically Recoverable Errors
The printer cannot print when automatically recoverable errors occur. When the conditions for recovery
described below are met, the printer automatically recovers from the error.
The printer cannot print while an error is left unsolved.
Error Error description Error LED status Condition for Recovery
Roll paper cover
open error
The roll paper cover was opened
during printing
ON The roll paper cover is closed
Head temperature error A high temperature outside the
thermal head drive operating
range was detected
ON When the thermal head cools

17
Chapter 1 Product Overview
Recoverable Errors
The printer cannot print when a recoverable error occurs. When the roll paper cover is closed, the power is
turned off and on again, or an error recovery command is received, the printer can recover from the error.
Unrecoverable Errors
The printer cannot print when an unrecoverable error occurs. If the error persists after turning the printer off
and then on again, the printer may be defective. Contact qualified service personnel.
Error Error description Error LED status Condition for Recovery
Autocutter error Autocutter does not work
correctly
ON Recovers from the error when
the jammed paper or foreign
matter is removed, and the roll
paper cover is closed
The error recovery command is valid only if a recoverable error (excluding automatically
recoverable errors) occurs.
Use the TM-T20III Utility to change the condition for recovery. For details, see the TM-T20III Utility
User's Manual.
CAUTION
Turn off the power immediately when an unrecoverable error occurs.
Error Error description Error LED flash code
R/W error in memory After R/W checking, the printer does not
work correctly.
High voltage error The power supply voltage is extremely
high.
Low voltage error The power supply voltage is extremely low.
CPU execution error The CPU is executing an incorrect address.
Internal circuit connection
error
Internal circuits are not connected
correctly.
LED OFF
LED ON
Approx. 320 ms

18
Chapter 1 Product Overview
Status Display
-: Changes depending on whether or not paper is detected.
*: The error LED flashing patterns are as follows.
Power LED Error LED Paper LED
Online ON OFF OFF
Initializing after power-on ON ON -
Running a self-test ON OFF -
Waiting to continue self-test ON OFF Flashing
Feeding using the Feed button ON OFF -
Waiting to execute a macro ON OFF Flashing
Roll paper cover open while the printer
is not printing
ON ON -
No paper ON ON ON
While updating firmware ON Flashing Flashing
While in forced firmware update mode ON ON ON
While in power off standby ON OFF Flashing
The network link is down ON Flashing*-
Waiting to print status sheet ON ON Flashing
LED OFF
LED ON
Approx. 640 ms
Approx. 5,120 ms

19
Chapter 1 Product Overview
NV Memory
The printer is equipped with the NV memory (Nonvolatile Memory) to store data even after the printer power
is turned off. NV memory contains the following memory areas for the user:
•NV graphics memory
•User NV memory
•Memory switches (Customized value)
•R/E (Receipt Enhancement)
•User-defined page
•Maintenance counter
NV Graphics Memory
Graphics, such as shop logos to be printed on receipts, can be stored. Even with a serial interface model whose
transmission speed is low, high speed graphics printing is possible.
Use the TM-T20III Utility to register graphics.
You can confirm the registered graphics in the NV graphics information print mode.
User NV Memory
You can store and read text data for multiple purposes, such as for storing a note including customizing or
maintenance information of the printer.
Memory Switches (Customized Value)
You can configure various settings of the printer.
For more information, see "Software Settings" on page 41.
R/E (Receipt Enhancement)
Graphics, such as shop logos to be printed on top or bottom of receipts can be registered.
Use the TM-T20III Utility to register graphics.
CAUTION
As a guide, NV memory rewriting should be 10 times or less a day when you program applications.
•For detailed information about the Epson TM-T20III Utility, see the TM-T20III Utility User's
Manual.
•For information about how to use the NV graphics information print mode, see "NV Graphics
Information Print Mode" on page 52.

20
Chapter 1 Product Overview
User-defined Page
You can store character data in the user-defined page (character code table: page 255) so that you can also print
characters not resident in the printer.
Maintenance Counter
With this function, printer information, such as the number of lines printed, the number of autocuts, and
printer operation time after the printer starts working, is automatically stored in NV memory. You can use the
counter information for periodical checks or part replacement.
You can also check the print head running length and number of times of autocutting with the self-
test (see "Self-test Mode" on page 52).