Radio Shack TRS-80 CGP-220 User manual

TRS-80 ~
CGP-220
OPERATION MANUAL
Catalog Number 26-1268
1tad1elhaek
TRS-BO
COMPUTER
PROOUCTS

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PURCHASEDFROMARADIOSHACKCOMPANY-OWNEDCOMPUTERCENTER,RETAILSTOREORFROMA
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SoftwareLicenseto CUSTOMERorto a transactionwherebyRADIOSHACKsellsor conveyssuchEquipmentto a thirdpartyfor leaseto
CUSTOMER.
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Contents
Introduction . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 1
1/ Some Background Information . . . .. . . . . . . . . . . . . . . . . 3
2/ Description ofthe CGP-220. . . . . . . . . . . . .. . . . . . . . . . 5
Front View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Top View . . . • . • . • . • • • . • . • • • • . • • • • . • . . • . • . • • • • • • . . 6
Rear View. . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . 7
3/ Setting Up the CGP-220........................... 9
Connecting the CGP-220 to an AC Power Source......... . 9
Paper Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Single Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Roll-Paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Setting the Green Lever ............................. 10
Unlocking the Carriage .......................... 11
Locking the Carriage ............................ 11
Checking the Ink-Jet Mechanism ..................... 11
Ink-Supply Pumping ............................... 12
Self-Test ........................................ 12
Connecting the CGP-220 to a TRS-80 .................. 12
Power-Up Sequence ................................ 13
Replacing the Ink Packs ............................ 13
4/ Using the CGP-220 (General Printer Operation) ..... 15
Control Codes ..................................... 15
Sending Control Codes from BASIC ................... 15
5/ General Control Codes ............................ 17
Line Feed/Carriage Return .......................... 17
Elongated Characters ............................... 17
Dot Pitch Selection ................................ 18
Print Head Positioning ............................. 18
Character Repetition ............................... 19
Color Selection .................................... 19
6/ Entering the Various Printing Modes ............... 21
The Text Mode .................................... 21
The Bit Image Mode ................................ 21
The Color-Scan Mode ............................... 21
7/ The Bit Image Mode .............................. 23
Printing Graphic Patterns ........................... 24
Line Feed ........................................ 25
Repeat Function ................................... 25
Color Function .................................... 25
Mixing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Leaving the Bit Image Mode ......................... 26
8/ The Color-Scan Mode ............................. 27
Printing Graphic Patterns ........................... 27
Mixing Colors .................................... 28
9/ Color Computer Screen Dump...................... 29
Appendix A/ Control CodeSummary .................. 31
Appendix B/ Characters Sets ......................... 33
Appendix C/ Programming Information ............... 37
Appendix D/ Care and Maintenance .................. 39
Appendix E/ Transportation and Storage .............. 41
Appendix F/ Troubleshooting ......................... 43
Appendix G/ Specifications .......................... 45
Appendix H/ Interface Specifications ................. 47
Appendix I/ Schematic Diagram ...................... 51

Introduction
Congratulations for selecting the TRS-80 CGP-220 Ink-Jet Printer!
The CGP-220 is a compact, "drop-on-demand" Ink-Jet Printer that can print
characters and graphics in seven colors: Black, Red, Green, Yellow, Blue, Magenta,
and Violet.
Some of its unique features include:
• Standard and Elongated characters.
• High speed printing-37 characters per second.
• Bit-addressable, minute graphics.
• 640 dots per line of high-resolution printing.
• Printing on plain single sheet paper or roll-paper.
The CGP-220 can also reproduce graphic displays from a TRS-80 Color Computer.
All you need, besides a 16K Color Computer, is the Radio Shack Color Computer
Screen Dump Program. The Screen Dump Program allows the CGP-220 to accept
graphic input from the Color Computer for printing in four colors.
Additionally, the CGP-220 has both serial and parallel interfaces for use with any
TRS-80 computer. Its large capacity Ink Packs let you print up to 4 million characters,
and, finally, the CGP-220 operates at an unusually low noise-level. All these features
set the CGP-220 apart, making it an all-purpose Printer that's a real pleasure to use.
1

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1/ SomeBackgroundInformation
There are two principal ways in which all colors are produced.
The first involves mixing light rays. In this system-commonly known as the "RGB"
method- Red, Green, and Blue light rays are projected on a surface (such as a theater
screen or a color monitor) to generate all other colors.
The second method-and you'll probably remember this from your junior high
school art class-is based on the mixture of pigments such as ink or paint. In this
method, the colors Yellow, Magenta, and Cyan are mixed in different combinations
to produce all other colors. This is called the "subtractive" system, although it is most
often known as the "YMC" method.
The CGP-220 uses the "YMC" method. Color monitors, on the other hand, use
light rays to create color, and, therefore, use the "RGB" method.
It is possible, however, to print graphic displays from a color monitor because the
CGP-220 is equipped with built-in software that allows conversion from the "RGB"
method to the "YMC" method. This means, simply, that you can use a Color
Computer to produce a graphic color display and then "dump" the picture to the
CGP-220 for printing.
Of course, you can manipulate colors directly in the Bit Image or the Color-Scan
Mode from a BASIC program. Color Screen Dumping isjust an extra convenience
that makes your CGP-220 more useful and a valuable addition to any computer
system.
3

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2/ DescriptionoftheCGP-220
Open the package and take out the CGP-220. Do not throw away the package material
or the box. They may be useful ifyou ever need to transport the Printer or send it
through the mail.
The CGP-220 package includes:
• A CGP-220 Ink-Jet Printer.
• A power cord.
• Three sheets oftest paper.
• This owner's manual.
To get the most benefit from your Printer, take some time now to familiarize yourself
with the various parts and controls.
CDPaper Cutter
(])Ink Pack
Compartment
@Paper Cover
@Paper Release Lever
®Manual Paper Feed Knob
1r:=--c"'1-~L--@ Power Switch:
OFF II loIIoN
(J)Control Panel
Figure 2-1 .Front View
CDPaper Cutter. When using Roll-Paper (26-1333), pull against edge of the Cutter
to tear paper off.
® Ink Pack Compartment. The Ink Packs are housed inside this compartment. Pry
open (compartment door swings down) with a coin or a flat object to change the
Ink Packs when necessary.
® Paper Cover. Keep Cover closed while Printer is in operation.
Raise it to load Roll-Paper, lock or release the Green Lever, and pump the Ink
Supply.
© Paper Release Lever. Pull Lever forward to insert or release paper. Push Lever
towards rear to secure paper in place.
® Manual Paper Feed Knob. Rotate towards the rear to advance the paper
manually.
® Power Switch. Press the side with red circleto turn the Printer ON. Press the
opposite side to turn the Printer OFF.
5

6
(J) Control Panel:
IRESTARTIB
□ READY
D ALERT
□ POWER
Figure 2-2. Control Panel
RESTART Switch. When you run out of paper, the Printer will stop printing. Load
paper and press this Switch to return the Printer to its status before the out-of-paper
condition occurred.
FEED Switch. Press this Switch once to advance paper one line. Keep pressing for
continuous feed. This Switch is operative only when the ON/OFF LINE Switch is set
to OFF LINE.
ON/OFF LINE Switch. This Switch sets the Printer ON or OFF LINE. When ON
LINE, the Printer can operate with a computer. To operate other front panel switches
or to stop printing, the Printer must be OFF LINE.
IMPORTANT NOTE FOR COLOR COMPUTER USERS.
Do not attempt to print when the ON-LINE/OFF-LINE switch is set to OFF-LINE. If
you do, unpredictable printing may occur.
READY Indicator. If illuminated, this indicator signals the CGP-220 is ON LINE
and ready to print.
ALERT Indicator. This Indicator willilluminate whenever the Printer is out of
paper, a carriage fault has been committed, or to signal some electrical problem.
POWER Indicator. This Indicator willilluminate whenever the Printer is turned ON.
Figure 2-3. Top View

CDRoll Paper Holder. Press toward left to load or remove Roll-Paper.
® Green Lever. The Green Lever can be used to lock the carriage and cap the ink
nozzles (to protect against vibrations during transportation and prevent ink from
drying or spilling), to unlock the carriage and uncap the nozzles, or to "pump"
the ink supply.
CDPowerCord Connector
© BaudRate
SelectSwitch:
®ParallelInterfaceConnector
600
Figure 2-4. Rear View
CDPower CordConnector. Connect the supplied power cord here.
® Parallel Interface Connector. If your Computer has parallel interface
capabilities, connect the appropriate Printer Cable here.
1111111111111111
@ Serial Interface Connector. If you are using a Color Computer, connect the
appropriate Printer Cable here.
2400
Note: Each printer interface connector becomes active when the Printer Cable is
inserted. Use either connector (parallel or serial) but never both at the same time.
@ Baud Rate Select Switch. Set Switch to the left for 600 baud; set to the right for
2400baud.
7

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3/ SettingUptheCGP-220
This section shows you how to set up your Printer so that you can begin using it as
quickly as possible.
Before getting started, however, you must choose an appropriate location to set up
your Printer.
Observe the following precautions when selecting a location:
• Avoid connecting the Printer to the same outlet as noise-generating equipment
(such as air-conditioners, copy machines, refrigerators, etc.).
• Avoid dusty places and direct sunlight, or extreme temperatures and humid
conditions.
• Place the Printer on a sturdy, flat work surface.
ConnectingtheCGP-220toanACPower
Source
Before plugging the power cord, be sure the CGP-220 Power Switch isin the OFF
position.
1. Connect the female end of the power cord to the Power Jack on the rear of the
CGP-220.
2. Connect the other end of the power cord to a 3-prong grounded outlet or to an
approved power strip such as Radio Shack's Automatic Power Controller
(26-1429). If you must use an extension cable, use the shortest one possible.
PaperLoading
The CGP-220 uses either Single-Sheets (26-1341) or Roll-Paper (26-1333).
Single-SheetPaperLoading
1. Turn the power OFF.
2. Move the Paper Release Lever forward.
3. Insert a sheet of paper into the Paper insertion slot at the end of the Paper Cover.
4. Push the Paper Release Lever toward the rear and turn the Manual Feed Knob to
pull the paper around until it feeds about 4" above the Paper Cutter.
5. Pull the Paper Release Lever forward again to align the paper, then push it toward
the rear.
6. Turn the Paper Feed Knob to return the paper to the desired printing position.
7. Turn the power ON.
After the paper is loaded and the power isON, check the ALERT Indicator. If it is
illuminated, press the RESTART. If it turns offyou may put the Printer ON LINE
and begin printing. If the Indicator remains lit, the paper isprobably loaded
incorrectly.
Once the paper is properly loaded, printing willcontinue until the paper's bottom
edge passes a "paper empty sensor." When this happens, the CGP-220 willgo OFF
9

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10
LINE and the ALERT Indicator willbegin flashing. You should then insert another
piece of paper and press the RESTART Switch. The CGP-220 willresume printing
from where it left off.
Note: Be sure to set the Paper Release Lever toward the rear after the paper is loaded
to avoid paper jam.
Roll-Paper
1. Be sure the power is turned OFF.
2. Open the Paper Cover. Press the Roll-Paper Holder toward the left. Insert the
right end of the Roll-Paper into the circular projection on the right side, and then
release the Roll-Paper Holder to secure the other end of the Roll-Paper.
3. Pull the Paper Release Lever forward.
4. Insert the Paper into the Paper Insertion Slot.
5. Push the Paper Release Lever toward the rear and use the Manual Feed knob to
pull the paper around until it appears between the platen and the Paper Cutter.
6. Pull the Paper Release Lever forward again to align the paper, then push it toward
the rear.
7. Turn the Manual Feed Knob to return the paper to the desired printing position.
8. Close the Paper Cover.
9. Turn the power ON.
After the paper is loaded and the power is ON, check the ALERT Indicator. ifit is
illuminated, press RESTART. If it turns off you may put the Printer ON LINE and
begin printing. If the Indicator remains lit, the paper is probably loaded incorrectly.
Note: Be sure to set the Paper Release Lever toward the rear after the paper is loaded
to avoid paperjam.
Settingthe GreenLever
The Green Lever performs three primary functions:
• First, it lets you lock the carriage and cap the ink nozzles. This protects the
Printer from vibrations during transportation and prevents the ink from drying or
spilling.
• Second, it unlocks the carriage and uncaps the nozzles to permit printing.
• Third, the Green Lever can also be used to "pump" the ink supply to provide
better printing quality.
0
0
Figure 3-1. Green Lever Settings
•

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Unlocking the Carriage
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 
Locking the Carriage


 
 
 


 

 




Checking the Ink-Jet Mechanism







 

11

12
Ink Supply Pumping
When the CGP-220 does not print or printing quality is poor, the problem may be
remedied by "pumping" the ink supply.
1. Turn the power ON and confirm that th Printer isOFF LINE.
2. Open the Paper Cover.
3. Press the Green Lever allthe waydown and hold it there for one second.
4. Release the Green Lever.
5. The ALERT Indicator willblink for about ten seconds. When it stops blinking,
lift the Green Lever to the top position.
6. Close the Paper Cover.
7. Check the Ink-Jet Mechanism by printing the test pattern again.
If the quality of the printed pattern is still inadequate, repeat Ink Supply Pumping.
A maximum of two "pumping" should suffice. After Ink Pack replacement or long
storage, however, five to six "pumpings" may be necessary.
Self-Test
In addition to checking the Ink-Jet Mechanism, you may check general printer
operation and printing quality with the CGP-220's built-in self-test.
1. Turn the power OFF.
2. Turn the power ON while pressing the FEED Switch.
3. Release the FEED Switch.
The CGP-220 willbegin the self-test, printing all the alphanumeric symbols that it is
capable of producing. Each line will be printed in a different color.
To stop the self-test simply turn the power OFF.
Connecting the CGP-220 to a TRS-80
When connecting the CGP-220 to a TRS-80 Computer, be sure to use the correct
printer cable. Table 1indicates the appropriate printer cable for each Computer; Table
2 tells you where the printer connector is located on each TRS-80.
Also, before making any connections be sure to turn the power to all system
components OFF.
TRS-80 to CGP-220 Cables
TRS-80
Model I (Exp. Interface)
Models 11/16/DT-1
Model Ill
Model4
Model 100
Color Computer
Cable Number
26-1401
26-4401
26-1401
26-1401
26-1409
26-3020
Table 1

TRS-80 Connection Points
TRS-80
Model I (Exp. Interface)
Models 11/16
Models111/DT-1
Model4
Model 100
Color Computer
Connector
Left side of E.I.
Rear Panel of Computer
Underneath Panel
Underneath Panel
Rear Panel of Computer
Rear Panel of Computer
Table2
1. Attach the molded male end of the printer cable to the connector on the left rear
of the CGP-220. Do not force the plug. If it doesn't fit, turn it over and try again.
2. Connect the other end of the cable to the Printer Jack of your Computer. See
your TRS-80's owner's manual for specific instructions.
3. If you're using the Serial Interface connection, set the Baud Rate Switch to the
appropriate position.
Important Note! You may use either the Serial or Parallel Interface connectors, but
never both at the same time.
Power-UpSequence
The precise power-up sequence willdepend upon your Computer. We suggest that
you consult your owner's manual for details on powering up your TRS-80 with
peripheral devices (such as printers).
Replacingthe Ink Packs
Your CGP-220 comes with two Ink Packs installed. The BlackInk Pack (26-1281)
can print about four million characters; the Tri-Color Ink Pack (26-1282), about three
million. '
When printing quality does not improve after repeated Ink-Supply Pumping and you
have already printed more than eight rolls of paper, it is likely that the Ink Packs are
exhausted.
To replace the Ink Packs:
1. Turn the power OFF.
2. Insert a coin or a small flat object in the opening of the Ink Pack Compartment
and, carefully, pry it open.
3. Grasp the empty Ink Pack by the sides and pull it out gently but firmly.
4. Becertain that the Ink Pack is empty by holding it sideways and then shaking it. If
the ink sack inside does not jiggle freely, the Ink Pack is empty.
5. Insert the new Ink Pack in place, making sure it stays firmly attached.
6. Pump the Ink Supply.
7. Close the Ink Pack Compartment.
Note: Dispose of used Ink Pack immediately; remaining Ink may spill.
13

14
Figure 3-2. Replacing the Ink Packs
Remember ...
• Use only Ink Pack replacements specially designed for the CGP-220 (BlackInk
Pack, 26-1281; Tri-Color Ink Pack, 26-1282.)
• Never refill empty Ink Packs.
• Operate the Printer only when both Ink Packs are installed.
• Insert Ink Pack replacements in their appropriate slots (do not interchange
them). The BlackInk Pack always goes in the left slot, the Tri-Color Ink Pack, in
the right slot.
Failure to observe the above precautions may damage your Printer.
Special Note: If the CGP-220 is operated in locations 1000 or more meters above sea
level (3,280'), low air pressure may cause Ink Supply malfunction. Should this occur,
leave the Printer unused for 24 hours so that the pressure inside the Ink Packs and
tubes equalizes to the air pressure outside. Then "pump" the Ink Supply. Also, ifthe
Printer is carried around, bubbles may appear inside the ink tube, causing irregular
printing. Leaving the unit unused for 6 hours and then "pumping" the Ink Supply
takes care of this.