Epson RP-U420 Series User manual

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Two-Station Printer
RP-U420 series
Specification
STANDARD
Rev. No. B
Notes
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SEIKO EPSON CORPORATION
MATSUMOTO MINAMI PLANT
2070 KOTOBUKI KOAKA, MATSUMOTO-SHI, NAGANO, 399-8702 JAPAN
PHONE[phone] FAX[phone]

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REVISION SHEET Sheet 1 of 3
The table below indicates which pages in this specification have been revised.
Before reading this specification, be sure you have the correct version of each page.
Revisions Design Section Sheet Rev. No.
Rev. Document WRT CHK APL Sheet Rev. Sheet Rev. Sheet Rev.
A Enactment Matsumoto -- Kanai IB19B43B
B Change II B20B44B
III B21B45B
IV B22B46B
23 B 47 B
24 B 48 B
1B25B49B
2B26B50B
3B27B51B
4B28B52B
5B29B53B
6B30B54B
7B31B55B
8B32B56B
9B33B57B
10 B 34 B 58 B
11 B 35 B 59 B
12 B 36 B 60 B
13 B 37 B 61 B
14 B 38 B 62 B
15 B 39 B 63 B
16 B 40 B 64 B
17 B 41 B 65 B
18 B 42 B 66 B
TITLE Front Part
RP-U420 series
Specification Cover Rev.
Sheet Scope General
Descriptions Table of
Contents Contents Appendix Total
(STANDARD) 13-- 2 2 71 5 84

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REVISION SHEET Sheet 2 of 3
The table below indicates which pages in this specification have been revised.
Before reading this specification, be sure you have the correct version of each page.
Revisions Design Section Sheet Rev. No.
Rev. Document WRT CHK APL Sheet Rev. Sheet Rev. Sheet Rev.
A Enactment 67 B
B Change 68 B
69 B
70 B
71 B
App.1 B
App.2 B
App.3 B
App.4 B
App.5 B
TITLE Front Part
RP-U420 series
Specification Cover Rev.
Sheet Scope General
Descriptions Table of
Contents Contents Appendix Total
(STANDARD) 13-- 2 2 71 5 84

Confidential
REVISION SHEET Sheet 3 of 3
REV. SHEET CHANGED CONTENTS
All All pages are renumbered.
1 1.2 Character Specifications
1) One-byte code font (added)
2) Two-byte code font (added)
2 1.5.1 Paper feed
1/6 inch →4.23 mm
7 1.12 Electrical Specifications
3) Current consumption (added)
1.13 Applicable Standards
Europe, Oceania (added)
17 2.1.2.7 Data Receiving Timing (changed)
22 3.1 Commands
ESC t, GS I, DLE EOT (added)
25 - 35 3.2.2 through 3.2.12 (added)
36,37 Table 3.3.1 and Table 3.3.2 Dip Switch 1
Bit 7 of DIP Switch 1 Reserved →Paper cutter
42 3.7 Hexadecimal Dump
3) <Example Printing> (corrected)
47 FF[Function] & [Description] (changed)
59 ESC t (added)
60 ESC z
[Format] Decimal 112
→122
[Default]
n
= 1 (added)
61 FS & and FS .
[Default] (added)
[Description] (changed)
62 GS I (added)
63, 64 GS V
[Function] (changed)
B
66 - 69 DLE EOT (added)
TITLE RP-U420 series
Specification
(STANDARD)

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RP-U420
Specification
(STANDARD) II
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BY USING THIS DOCUMENT, YOU AGREE TO ACIDE CY THE TERMS OF THIS AGREEMENT. PLEASE
RETURN THIS DOCUMENT IMMEDIATELY IF YOU DO NOT AGREE TO THESE TERMS.
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General Notice: Other product and company names used herein are for identification purposes only and may
be trademarks of their respective companies.
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RP-U420
Specification
(STANDARD) III
Features
This printer is a two-station printer that is light and offers excellent reliability, The design of this printer
also emphasizes the needs of the user. The printer has the following features:
•High-speed printing, light weight, one line validation, and low-noise operation
•Excellent universality of control
•Built-in drawer-kick interface provides capability to drive two drawers
•Selectable character fonts (7 ×9, 16 ×9 for Chinese Character)
•Can apply for Taiwan receipt printing with Taiwan mode using DIP switch setting (for RP-U420 with
Taiwan black mark sensor model)
•Takeup device installed
•The standard model is equipped with an autocutter. A manual cutter model is also available.
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Specification
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Table of Contents
I. BASIC SPECIFICATIONS.................................................................................................................... 1
1.1 Printing Specifications...................................................................................................................1
1.2 Character Specifications ............................................................................................................... 1
1.3 Roll Paper Supply Unit ..................................................................................................................1
1.4 Takeup Device .............................................................................................................................. 2
1.5 Paper and Paper Feed Specifications...........................................................................................2
1.5.1 Paper feed ............................................................................................................................ 2
1.5.2 Paper specifications.............................................................................................................. 2
1.6 Paper cutter................................................................................................................................... 2
1.7 Stamp............................................................................................................................................ 3
1.8 Buzzer ........................................................................................................................................... 3
1.9 Ribbon Cassette............................................................................................................................ 4
1.10 Printing area................................................................................................................................ 4
1.11 Receive Buffer............................................................................................................................. 7
1.12 Electrical Specifications...............................................................................................................7
1.13 Applicable Standards ..................................................................................................................7
1.14 Reliability..................................................................................................................................... 7
1.15 Environmental Specifications......................................................................................................7
2. CONFIGURATION............................................................................................................................... 9
2.1 Interface Specifications................................................................................................................. 9
2.1.1 RS-232 Serial Interface......................................................................................................... 9
2.1.2 IEEE 1284 Bidirectional Parallel Interface (Parallel Interface Specifications)..................... 13
2.2 Connectors.................................................................................................................................. 19
2.2.1 Interface connectors ........................................................................................................... 19
2.2.2 Power supply connector...................................................................................................... 19
2.2.3 Drawer kick-out connector (modular connector).................................................................20
3. FUNCTIONS...................................................................................................................................... 22
3.1 Commands.................................................................................................................................. 22
3.2 Character Code Tables............................................................................................................... 24
3.2.1 Page 0 (PC437: U.S.A. Standard Europe) (International character set: U.S.A.)................ 24
3.2.2 Page 1 (Katakana).............................................................................................................. 25
3.2.3 Page 2 (PC850: Multilingual) ..............................................................................................26
3.2.4 Page 3 (PC860: Portuguese).............................................................................................. 27
3.2.5 Page 4 (PC863: Canadian-French) ....................................................................................28
3.2.6 Page 5 (PC865: Nordic)...................................................................................................... 29
3.2.7 Page 16 (WPC1252)........................................................................................................... 30
3.2.8 Page 17 (PC866: Cyrillic #2)............................................................................................... 31
3.2.9 Page 18 (PC852: Latin 2) ................................................................................................... 32
3.2.10 Page 19 (PC858: Euro)..................................................................................................... 33
3.2.11 Page 254 (PC857: Latin 5) ...............................................................................................34
3.2.12 Page 255 (Space Page)....................................................................................................35
3.3 Switches and Buttons..................................................................................................................36
3.3.1 Power switch....................................................................................................................... 36
3.3.2 Paper feed buttons.............................................................................................................. 36
3.3.3 Stamp button....................................................................................................................... 36
3.3.4 DIP switches ....................................................................................................................... 36
3.4 Panel LED Indicators................................................................................................................... 38
3.4.1 Panel LED indicators ..........................................................................................................38
3.5 Error Processing.......................................................................................................................... 39
3.5.1 Error types........................................................................................................................... 39
3.5.2 Operation when an error is detected................................................................................40
3.6 Self-test ....................................................................................................................................... 41
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3.7 Hexadecimal Dump..................................................................................................................... 42
3.8 Paper Detectors .......................................................................................................................... 43
3.9 Buffer-full Printing........................................................................................................................ 43
4. CASE SPECIFICATIONS.................................................................................................................. 44
4.1 External Dimensions and Mass................................................................................................... 44
4.2 Color............................................................................................................................................ 44
4.3 External Appearance...................................................................................................................44
5. ACCESSORIES AND OPTIONS....................................................................................................... 45
5.1 Standard Accessories ................................................................................................................. 45
5.2 Options........................................................................................................................................ 45
5.3 Interface Board............................................................................................................................ 45
6. COMMANDS...................................................................................................................................... 46
6.1 Command Notation ..................................................................................................................... 46
6.2 Explanation of Terms..................................................................................................................46
6.3 Command Descriptions............................................................................................................... 47
LF....................................................................................................................................... 47
FF....................................................................................................................................... 47
CR...................................................................................................................................... 48
RS...................................................................................................................................... 48
ESC !
n
............................................................................................................................... 48
ESC %
n
............................................................................................................................ 49
ESC &
y c1 c2 [x1 d1...d(y ×x1)]...[xk d1...d(y ×xk)]
........................................................ 49
ESC ∗
m nL nH d1 ... dk
.................................................................................................... 51
ESC <................................................................................................................................. 53
ESC =
n
.............................................................................................................................. 53
ESC ?
n
.............................................................................................................................. 53
ESC @............................................................................................................................... 54
ESC R
n
............................................................................................................................. 54
ESC c 0
n
........................................................................................................................... 55
ESC c 3
n
........................................................................................................................... 56
ESC c 4
n
........................................................................................................................... 57
ESC c 5
n
........................................................................................................................... 57
ESC d
n
.............................................................................................................................. 58
ESC f
t1 t2
.......................................................................................................................... 58
ESC o................................................................................................................................. 58
ESC p
m t1 t2
..................................................................................................................... 59
ESC t
n
............................................................................................................................... 59
ESC z
n
.............................................................................................................................. 60
FS &................................................................................................................................... 61
FS . .................................................................................................................................... 61
GS I
n
................................................................................................................................62
➀GS V
m
➁GS V
m n
...................................................................................................... 63
GS r
n
................................................................................................................................. 65
DLE EOT
n
......................................................................................................................... 66
DLE ENQ
n
........................................................................................................................ 71
DLE DC4
n m t
................................................................................................................... 71
APPENDIX A. MISCELLANEOUS NOTES..................................................................................App.1
APPENDIX B. ADJUSTING THE PAPER ROLL NEAR-END SENSOR LOCATION..................App.2
APPENDIX C. USING THE RELEASE LEVERS.........................................................................App.3
APPENDIX D. INSERTING THE VALIDATION PAPER..............................................................App.4
APPENDIX E. NOTES ON USING THE DRAWER KICK-OUT CONNECTOR ..........................App.5
IV
1

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I. BASIC SPECIFICATIONS
1.1 Printing Specifications
1) Printing method: Serial impact dot-matrix
2) Head wire configuration: 9-pin serial configuration
3) Printing directions: Bi-directional printing
4) Printing speed: Approx. 3 lps (lps: lines per second)
(Excludes data transfer and processing time)
5) Maximum print positions Receipt / journal printing : 216
Validation printing:495
Position spacing: Approx. 0.17 mm (half dot pitch)
Table 1.1.1 Character Dimensions, Characters Per Inch, Characters Per Line
Character configuration
Horiz. ×Vert. Character type
Character
dimensions
W ×H (mm)
Dot spacing
between
characters
Characters
per line
(cpl)
Characters
per inch
(cpi)
7 ×9 ANK 1.31 ×3.1 2 Half-dots 24 16.6
16 ×9 Chinese 2.84 ×3.1 2 Half-dots 12 8.3
NOTE: Neighboring-position printing is not possible.
Validation printing is for 1 line.
6) Characters per line Using a 7(position) ×9(wire) font with 2-position column spacing.
Receipt / Journal printing : 24 columns
Validation printing : 55 columns
1.2 Character Specifications
1) One-byte code font
Number of characters: Alphanumeric characters: 95
Extended graphics: 128 ×12 pages
(including two space pages)
International characters: 37
2) Two-byte code font
Traditional Chinese character (Based on Big 5 code table)
•Total 13053 characters (*1)
(*1): When printing Kanji characters which consist of many lines, be sure to consider that some
of characters may not be readable.
1.3 Roll Paper Supply Unit
1) Supply method: Drop-in method
2) Near end detector: Near-end detectors for journal and receipt are standard.
Detection method: By mechanical microswitch
Paper roll near-end detection is adjustable.
Refer to Appendix B for instructions on adjusting the near-end detector
location.

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1.4 Takeup Device
The take-up mechanism is integrated into the main unit. Journal paper is taken up automatically when it
is fed.
1.5 Paper and Paper Feed Specifications
1.5.1 Paper feed
1) Paper feeding method: Friction feed
2) Paper feed interval: 4.23 mm
3) Fast paper feed speed: Continuos paper feeding (*): 30 lps (lps: lines per second)
Other fast feeding: 12 lps (lps: lines per second)
(*) •When the first 30-line paper feeding with the ESC d
n
command is executed.
•When the paper is fed with the GS V
m n
command in standard mode.
1.5.2 Paper specifications
The following paper must be used to maintain high print quality.
(a) Paper roll
Width 44.5 ±0.5 mm
Maximum diameter 83 mm
Thickness 0.06 to 0.09 mm
Weight 52.3 to 64.0 g/m2
(b) Validation paper
1) Single sheet
Dimensions: Width: 135-210 mm ×height minimum 70 mm
Thickness: 0.07 - 0.14 mm
2) Multiple sheet
Configuration: Normal paper + carbon paper or pressure-sensitive paper
Dimensions: Width:135 - 210 mm ×height minimum 70 mm
Number of layers: Maximum2 (1 original + 1 copy)
Combined paper thickness: Maximum 0.14 mm
3) Other Specifications
➀Do not use paper that might interfere with operation of the sensors, such as tracing or
coated paper.
➁When using validation printing (factory option), use paper with a light opacity of 70% or
more.
➂Use paper that is free from wrinkles, creases, and wraps.
1.6 Paper cutter
Autocutter is installed as a standard. (Manual cutter type is available as a factory option)
1) One point left uncut or three points uncut can be selected for the autocutter. (refer to Section 6.3
Command Description GS V)
2) If the Taiwan mode is set with the DIP SW 1-8, paper is cut automatically when PF or FF command is
executed. (refer 3.3.4 ∗1))

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1.7 Stamp
•The standard model provides a stamp mechanism.
•The stamp material must be provided by the user.
•A stamp frame can be provided as an option.
1) Material: Porous rubber
2) Stamp face dimensions: 30(W) ×20(H)mm
NOTE: Stamp face characters should be equal in the area both above and below the
centerline.(When the difference is extreme, part of characters may not print.)
3) Recommended stamp model Shachihata XS-20
Fujicopian CSP-2030D
4) Recommended ink Shachihata Y-34
Fujicopian Super Ink (purple)
NOTES: 1. Because the stamp is located near the paper exit slot of the paper feed mechanism, the
knurled screw of the paper holder may become stained when replacing the stamp or
refilling ink.
2. To refill ink, inject 2-3 drops through each round hole in the rear of the stamp set.
3. After refilling ink, leave the unit upturned until the ink has fully spread (3 hours is
recommended time).
4. Use only the recommended ink to prevent leaks during and after refilling.
5. Do not change from using refill ink made by one manufacturer to ink made by another
manufacturer.
5) Stamp button: Installed as a standard
Refer to Section 3.3.3 in detail.
1.8 Buzzer
A buzzer is installed.
The buzzer cannot sound if DIP SW2-3 is set to Off. (See Table 3.3.2 for the DIP SW2)
The conditions when the buzzer beeps are as follows if DIP SW2-3 is set to On.
•When an error occurs.
•When the DLE ENQ command is executed.
•When the ESC @ command is executed.
•When the self-test is executed (See Section 3.6, Self-test).
•When the hexadecimal dump is executed (See Section 3.7, Hexadecimal Dump).

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1.9 Ribbon Cassette
The ribbon is fed automatically when the motor runs.
Type: EPSON ERC-32(P)
Use of a ribbon cassette other than the specified type can degrade printer performance and reduce
reliability and life expectancy.
Color: Purple(single-color)
Ribbon life: 6,000,000 characters
(24 VDC, 25°C, energizing width, 7 ×9 font, receipt/journal 9 + 9 columns, continuous printing, ASCII
code hex 20-5F rolling pattern printing))
1.10 Printing area
1) Receipt/journal printing
Refer to Figure 1.10.1.
Refer to Figure 1.10.3 for the Taiwan receipt.
(Taiwan receipt can be issued easily in Taiwan mode with DIP SW 1-8 setting)
2) Validation Printing (one-line validation)
Single-line validation printing can be performed.
Since there is no validation paper hold mechanism, the validation paper should be inserted using
the guide on the journal side to position the paper. During printing, the paper should be held in
place, for example, by pushing it against the case.
NOTES: 1. Incorrect printing may result if the above procedure is not followed.
2. If the paper is inserted but is not supported by hand, it may move when the print head
moves from the journal side to the receipt side.
The user should define the home position of the print head on the receipt side and have
the head return to this position after completing receipt printing.
The printable area is shown in Figure 1.10.2.
3. Refer to Appendix D for inserting the validation paper.

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(39.1 mm)
Stamping position
10-line feed (33.3mm)
Autocut driving position
1-line feed
Stamp
: Printed line
Receipt printing pattern
Journal printing pattern
Autocut position (one
point left uncut:
sample
)
3.8 mm
36.7 mm
4.0 mm
4.5 mm
36.7 mm
3.3 mm
44.5±0.5 mm
44.5±0.5 mm
Autocut position (three point left uncut: sample)
Stamp Note : Dimension for using 7×9(2 position space) font characters
.
Cut position marked with
∗) is applied for the manual
cutter model.
(2mm)
(44.4mm)
∗)
∗
)
Manual cut position
Emer
g
ency paper cut
Figure 1.10.1 Printing Area
Printable area: 84.5 mm
Validation sensor pulse
10 mm
22 mm
2 mm
8 mm
Note : Dimension for using 7 ×9 (2 position space)font characters
Figure 1.10.2

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∗1∼6
NOTES:
•The paper cut position may be
unstable to the mark sensor position,
because the paper feed pitch of this
printer is 4.23 mm {1/6”}.
•For the cut position by an emergency
cutter, refer to Figure 1.10.1.
[Units: mm]
Figure 1.10.3

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1.11 Receive Buffer
4 KB
1.12 Electrical Specifications
1) Use EPSON PS-170
2) Voltage: 24 V
±5%
3) Current consumption (at 25°C):
During operation:
Mean: Approximately 0.75A (α-N 24 columns printing)
Standby:
Mean: Approximately 0.12A
1.13 Applicable Standards
Taiwan: EMI Class B
Europe: EMC: CE marking
EN55022 Class B
EN55024
Safety standard: EN60950 (TUV)
Oceania: EMC: AS/NZS 3548 Class B
1.14 Reliability
1) Life: 8,000,000 lines
2) MCBF: 20,000,000 lines
3) Print head life: 300,000,000 dots/wire
4) Auto cutter life: 800,000 times
1.15 Environmental Specifications
1) Temperature
During operation: 5 to 45°C {41°to 113°F}. (At 34°C {93°F} or higher, there are humidity
restrictions; refer to Figure 1.15.1.)
During storage: -10 to 50°C {14°to 122°F} (excludes paper and ribbon)
2) Humidity
During operation: 10 to 90% (no condensation)
During storage: 10 to 90% (no condensation; excludes paper and ribbon)

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Operating
environment range
Ambient temperature (°C)
Relative humidity (%RH)
45°C, 40%
34°C, 90%
50403020100
80
60
40
20
Figure 1.15.1 Operating Temperature and Humidity Range
3) Vibration resistance
While packed: Frequency 5 to 55 Hz
Acceleration Approximately 19.6 m/s2{2 G}
Sweep 10 minutes (half cycle)
Time One hour
Directions X, Y and Z
4) Impact resistance
While not packed: Height: 5 cm
Directions 4 sides, supported on one side
While packed: Height: 80 cm
Directions 1 corner, 3 edges, 6 sides

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2. CONFIGURATION
2.1 Interface Specifications
2.1.1 RS-232 Serial Interface
2.1.1.1 Specifications
Data transmission: Serial
Synchronization: Asynchronous
Handshaking: DTR/DSR or XON/XOFF control
Signal levels: MARK = -3 to -15 V ... logic ‘1’ / OFF
SPACE = +3 to +15 V ... logic ‘0’ / ON
Baud rate: 9600 , 19200 bps (bps: bits per second)
Data word length: 7 or 8 bits
Parity: None, even, odd
Stop bits: 1 or more
Connector: D-SUB 25 (female) or equivalent
2.1.1.2 Online/Offline switching
The printer does not have an online/offline button. The printer goes online or offline under the following
conditions:
<Conditions to go offline>
1)When the printer cover is open
2)Between the time when the power is turned on and when the printer is ready to receive data.
3)During the self-test.
4)During paper feeding using the receipt/journal paper feed button.
5)During the printer stops printing due to a paper-end.
6)When an error has occurred.
<Conditions to go online>
1)Automatically after the time when the power is turned on (including reset using the interface) when
the printer is ready to receive data.
2)Automatically after the self-test.
3)Automatically after the paper feeding is stopped by releasing the receipt/journal paper feed button.
4)After the time when the paper loading is completed, using DLE ENQ 1 or DLE ENQ 2 command.
The receipt/journal paper out (PAPER OUT) LEDs are off after the paper loading is completed.

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2.1.1.3 Interface connector terminal assignments and signal functions
Table 2.1.1 Interface Pin Assignments and Functions
Pin
No. Signal Name Signal Direction Function
1 FG - Frame ground
2 TXD Output Transmit data
3 RXD Input Receive data
4 RTS Output Same as DTR signal (same as pin 20)
6 DSR Input Indicates whether the host can receive data. SPACE indicates that the
host can receive data, and MARK indicates that the host cannot receive
data. When DTR/DSR control is selected, the printer transmits data after
checking this signal. When XON/XOFF control is selected, the printer
does not check this signal. Changing the DIP switch setting enables this
signal to be used as a reset signal for the printer. The printer is reset
when the signal remains MARK for 1 ms or more.
7 SG - Signal ground
DTR Output 1) When DTR/DSR control is selected, this signal indicates whether the
printer is BUSY. SPACE indicates that the printer is READY to receive
data, and MARK indicates that the printer is BUSY. DIP switch 1-6
switches conditions for BUSY. The BUSY (MARK) condition is
changed using DIP switch 1-6 as follows: Dip Switch 1-6
Status
Printer Status ON OFF
1) The period from power-on (or initialization of the mechanism due
to resetting through the interface) until the printer is ready to
receive data.
BUSY BUSY
2) During the self-test. BUSY BUSY
3) During paper feeding using the FEED button. ---- BUSY
4) When the printer stops due to a paper-end (ESC c 4). ---- BUSY
Offline
5) During an error condition. ---- BUSY
6) When the receive buffer is full (*1). BUSY BUSY
20
2) When XON/XOFF control is selected, this signal indicates whether the
printer is properly connected and is ready to receive data. SPACE
indicates that the printer is properly connected and is ready to receive
data. This signal is always SPACE except during the following periods:
•From power-on until the printer is ready to receive data.
•During the self-test.
25 INIT Output Changing the DIP switch setting enables this signal to be used as a reset
signal for the printer. The printer is reset when the signal remains
SPACE for 1 ms or more.
*1 •The period from when the remaining space in the receive buffer drops to 256 bytes until it
increases to 1000 bytes is called the "buffer full state."
•Data received when the remaining space in the receive buffer is zero bytes is ignored.

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2.1.1.4 XON/OFF transmission timing
When XON/OFF control is selected, the printer transmits XON or XOFF signals as follows. Transmit
timing depends on the setting of DIP switch 1-5.
Table 2.1.2 XON/XOFF Transmission Timing
Dip Switch 1-5 Status
Printer Status ON OFF
1)When the printer first goes online after power
on or after resetting through the interface. Transmission Transmission
2)When the receive buffer is released from the
buffer-full state. Transmission Transmission
3)When the printer status changes from offline
to online. -- Transmission
[XON
transmission]
4)When the printer recovers from an error
through a command. -- Transmission
5)When the receive buffer is full. Transmission Transmission[XOFF
transmission] 6)When the printer status changes from online
to offline. -- Transmission
NOTES: •The XON code is <11>H and the XOFF code is <13>H.
•In case 3), XON is not transmitted when the receive buffer is full.
•In case 6), XOFF is not transmitted when the receive buffer is full.
•When the DIP SW1-5 is set to Off, XON is not transmitted if the printer is offline state in
case 2).
2.1.1.5 Example serial interface connection
Host Printer
TXD-------------------------RXD
DSR ------------------------DTR
CTS-------------------------RTS
RXD ------------------------TXD
DTR ------------------------DSR
FG --------------------------FG
SG --------------------------SG
•When connecting the printer to a DCE (DCE: Data Circuit Terminating Equipment), set the
handshaking so that the transmitted data can be received.
•Transmit data to the printer after turning on the power and initializing the printer.

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2.1.1.6 Notes on setting DIP switch 1-6 to on
1) The printer mechanism stops but does not become BUSY in the following cases:
•When an error occurs.
•When the printer stops printing due to a paper-end.
•When paper is fed using the feed button.
2) When using the DLE ENQ command, make sure that the receive buffer does not become full.
•Notes on using a host that cannot transmit data when the printer is BUSY:
If an error occurs when the receive buffer is full and the printer is BUSY, the DLE ENQ commands
cannot be used.
•Notes on using a host that can transmit data when the printer is BUSY:
If a DLE ENQ command is used while sending bit-image data, and the receive buffer-full state is
encountered during transmission of the data, the DLE ENQ is processed as bit-image data.
In addition, the data transmitted during the receive buffer-full state may be lost.
Example:
Check the status with GS r for each line of printing transmitted. Make sure the data for printing
each line does not cause the printer to enter the receive buffer-full state.
2.1.1.7 Notes on resetting the printer using the interface
The printer can be reset through the interface (pins 6 or 25) by changing the DIP switch settings
accordingly (Refer to Table 2.1.3).
Table 2.1.3 Switching of the Reset Condition
Pin No. DIP Switch Reset Condition
Pin 6 (DSR) DSW 2-2: ON MARK input
Pin 25 (INIT) DSW 2-1: ON SPACE or TTL-HIGH level voltage signal input
To reset the printer, the conditions given below must be satisfied:
<DC characteristics>
Table 2.1.4 DC Characteristics of the Reset Condition
Item Symbol Pin 6 (DSR) Pin 25 (INIT)
Input HIGH level voltage V IH +3 to +15 V +2 to + 15 V
Input LOW level voltage V IL -15 to -3 V -15 to + 0.8 V
Input HIGH level current I IH 5 mA (maximum) 1 mA (maximum)
Input LOW level current I IL -5.3 mA (maximum) -2 mA (maximum)
Input impedance RIN 3 kΩ(minimum)