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VIC 20 



There are many outstanding features in the 
VIC 20. It is easy to create colorful graphic dis¬ 
plays and three-part harmony sound. Programs 
are available on cartridges, cassette tapes and 
floppy diskettes. Game controllers can be 
plugged into the unit, like paddles, joystick, or 
light pen. A low-cost modem makes the VIC 
into an extremely inexpensive ($500 range) 
terminal. Disk, printer, and other peripherals will 
be available soon. Compared to other systems 
like the TRS-80 color computer, Atari 400, APF 
Imagination Machine, and Sinclair ZX-80, the 
VIC 20 emerges as the clear leader in price,/ 


The top row of keys contains the keys numbered 
1 through 8, which are also marked with the 
names of the 8 colors available for characters. 
By holding down the CTRL key and striking one 
of these color keys, you will cause the character 
color to change. 

When the VIC is turned on, the screen is white 
with a light blue (cyan) border, and any 
characters you type will appear in dark blue. 
IVpe a few letters or words and see for yourself. 

Now hold down the CTRL key, hit the key 
marked BLK (black), and type a few words. The 
letters you type are now appearing in black. 

Tly changing the letters to other colors. 

The front of the 9 key is marked RVS ON. When 
you hold down the CTRL key and hit RVS ON, 
the VIC switches to reverse letters: instead of 
black letters on a white background, you will 
be typing white letters on a black background. 
Hit CTRL and RVS ON and type a few words. Try 
changing colors and typing in different symbols. 
Holding CTRL and striking RVS OFF (on the 0 
key) will return to normal, unreversed letters. 

Now hold down SHIFT and hit RETURN, which 
brings you to the beginning of the next line 
without a SYNTAX ERROR message, 

The colors of the screen and border can also 
be changed. First, change the cursor to cyan by 
holding CTRL and hitting CYAN. Type in the 
following instruction: 

POKE 36879,8 (and hit RETURN) 

The screen and border will change to black. All 
the letters on the screen will remain there. Try 
out the following POKES to change the screen 
and border colors: 

POKE 36879,9 (RETURN) 

POKE 36879,27 (RETURN) 

POKE 36879,168 (RETURN) 

There are eight possible colors for the letters 
and the border, and sixteen possible colors for 
the screen. 


There are five different POKEs used to demon¬ 
strate sound. Type the following: 

POKE 36878,15 

This turns the volume of the VIC to the loudest 
setting. Now try: 

POKE 36874,200 
POKE 36875,200 
POKE 36876,200 

These three memory locations are the three 
voices of the VIC, each an octave apart, which 
can play tunes and sound effects. Each voice 
has three octaves, so the total range of the VIC 
is five octaves. 

To turn off the sounds, type: 

POKE 36874,0 
POKE 36875,0 
POKE 36876,0 

There is also a fourth voice available for 
sounds, a white-noise generator. By putting 
numbers in this voice, you can control the 
frequency of the noise. Try these: 

POKE 36877,140 
POKE 36877,200 
POKE 36877,250 
To stop the sounds, type:^ 

POKE 36877,0 
POKE 36878,0 


The VIC has a special set of graphic characters, 
useful in drawing charts and playing games. 
Most keys on the keyboard have two graphic 
symbols inscribed on the front side. By holding 
down the SHIFT key and typing the characters, 
you will display the graphic character on the 
right. By holding down the key with the 
COMMODORE symbol and typing, you will 
display the graphic symbol on the left side. 

Try this: 

Hold down SHIFT and hit the letters O and P, 

hold down SHIFT and hit RETURN. Still holding 
SHIFT type L and the @ key You have created a 
box on the screen! 

The graphic set includes the four playing 
card symbols (on the A, S, Z, and X keys), two 
ball symbols (Q and W), eight different horizontal 

lines. (To make these try the following sequence: 

SHIFT F, SHIFT R, 0 @) and many more. 

Upper/Lower Case 

The VIC contains two complete character sets. 
The normal set is the one you have been using. 
There is also a second character set, containing 
upper and lower case letters and some graphic 
symbols. To enter upper/lower case, hold down 
the SHIFT and COMMODORE keys at the same 
time. Any characters already on the screen 
will be changed to the new characters. Upper 
case letters become lower case, right-side 
graphics become upper case letters, and the 
left-side graphics remain the same. 

Now the keyboard of the VIC acts just like a 
typewriter. The letter keys will display lower 
case letters. To get upper case, hold down the 
SHIFT and hit that letter. The graphic characters 
on the left side of the keys remain unchanged. 

Cursor Movement 

The VIC allows the cursor (that blinking square 
on the screen) to move anywhere you like on 
the screen. The two keys marked CRSR, one with 
up and down arrows, the other with left and 
right arrows, are the cursor control keys. Hit the 
key with the right arrow and the cursor will 
move to the right. If you keep this key held down 
for at least a second, this movement will repeat 
automatically. Now hold down the SHIFT and hit 
the same key The cursor moves in the opposite 
direction. Tty hitting the key with the down 
arrow. This allows you to move the cursor down. 
If you hold the SHIFT while hitting this key, the 
cursor moves up. 

The key marked HOME will move the cursor 
to the upper left corner of the screen, called the 
"home" position. If you hold down the SHIFT and 
hit this key, the entire screen will clear off. 

Now type the numbers 12345 on the screen, 
but don't hit RETURN yet. Hit the key marked 
DEL, and the last character to the left of the 
cursor is deleted. Hold the SHIFT and hit the left 
arrow until the cursor is on top of the 2 on the 
screen, and hit the DEL. All of the characters to 
the right on the line moved over to fill in the 
space of the deleted character. Now hold down 
SHIFT and hit the DEL key. Each time you hit 
this key you will INSert an extra space at the 
position on the line. This is extremely useful in 
editing your programs. 

Troubleshooting Chart 





VIC not "on" 

Make sure power 
switch is in "on" 

VIC not plugged in 

Check power 
socket next to 
power switch 

Bower supply not 
plugged in 

Check connection 
with wall outlet 

Bad fuse in VIC 

Take VIC to your 



Service Center for 
replacement of 

(First, try turning VIC 
off for a few seconds 
then back on) 

TV on wrong channel 

Check Channel 3 
and 4 tor picture 

Incorrect hookup 

VIC hooks up to 
"VHF" terminals 
on TV 

Modulator not 
plugged in 

Check connection 
at 5-pin Video Port 

Modulator on wrong 

Flip switch on 

Video cable not 

Check connection 
on modulator 


Poorly tuned TV 

Retune TV 



Bad color adjustment 
on TV (see "picture 
without color") 

Adjustment color/ 
controls on TV 


TV volume up too 
high (see "picture 
without color") 

Adjust volume 
of TV 



TV volume too low 

Adjust volume 
of TV 


Switchbox set to "TV" 

Change switch to 

'The VIC uses a 3 amp SLO-BLO fuse. 

'Some VIC's may have a separate switchbox and some may have the 
TV/Computer settings built into the modulator box. 

Please see Display information on reverse side. 


The following information is provided to help 
you set up and display the VIC Personal 
Computer at consumer/trade shows and 


■ VICs 

■ Color monitors or TVs (1 per VIC) 

■ Electric outlets (2 per VIC) 

■ Cassette decks (1 per VIC) 


There are three specific tasks for VICs at 
computer shows: 

■ Free-running demo— The free-running demos 
should be placed as high as possible, on large 
size (17 or 19 inch) TV screens. The VIC can be 
taped (securely!) on top of the monitor or TV 
so that it cannot be disturbed. The program is 
loaded at the start of the day only 

■ Continuous game— The VICs used for game 
playing should be placed to the sides of the 
display area. Try to conceal all cables (this 
can be done with tape). Games should be on 
a cartridge, which should be securely taped 
or otherwise fastened to the VIC. Also, keep an 
eye on this machine in case an ingenious 
player finds a way to "crash" it. 

■ Available for use— VICs without specific tasks, 
or with tasks that require monitoring by the 
staff, should be in the center of the display 
area. Booth staff members should be able to 
load and run quick demonstration programs, 
or demonstrate the VIC directly (see HOW TO 
DEMONSTRATE THE VIC). You may wish to tilt 
these VICs so that the keyboard is displayed 
better, which also aids the VIC in dissipating 


Once a program is loaded from the cassette 
deck, it is wise to disconnect and hide the deck 
and the program tape. Do not leave any impor¬ 
tant programs, documentation, or other material 
out where it can be pilfered. 


(See Tl-oubleshooting Chart) 

Loading Demo Programs 
Erom Tape Cassette 

The VIC works with the standard Commodore 
Tape Cassette Recorder. Call or write your 
Commodore representative to obtain VIC 20 
demonstration tapes. 

Features To Demonstrate 

(manually or using demo tapes) 

■ Color from the keyboard 

■ Sound (convert the VIC keyboard to a PIANO 
or play songs) 

■ Programming.. .like the PET 

■ Programs on tape with cassette recorder 

■ Programs on plug-in cartridge 

■ The VIC owners manual, PERSONAL 

Points To Mention 

■ User Manual written for the first time 
computerist. Some advanced programming 
information is contained in the appendix. A 
Programmers Reference Guide will be avail¬ 
able at a price of $ 15.00. 

■ VIC Programs come in five "flavors": 

1) Recreation (games) 

2) Education 

3) Home Utility 

4) Business 8c Calculation 

5) Computing Aids 

Peripherals And Accessories 

■ Cassette Tape Recorder 

■ Memory Expander Cartridges 

■ Plug-in Programs 

■ Master Control Panel (accepts six separate 
cartridges including IEEE for PET peripherals) 

■ Modem (Telecommunications) 

■ Dot Matrix Printer (80 columns) 

■ Single disk drive 

■ VIC Learning Series (book and 
cartridge sets—Vol. I is called 
"Introduction to Computing") 

■ Joystick and game paddles 

brought: to you by 

http:/ /commodore-international/ 

commodore international historical society 

this document was generously 
contributed by 
Michael Tomczyk 

Technical Information 

Microprocessor: 6502A 
Word size: 8 bits 

Memory: 5 K RAM (3.5K is user accessible) 
16 K ROM (internal) 

Expandable to 32K RAM/ROM 
Screen size: 22 columns x 23 lines 
High resolution: 176x 184 pixels 
Programmable Function Keys: 12 functions 
Graphics: keystroke or hi- resolution 
Color: 8 character colors 
8 border colors 
16 screen colors 
Sound: 3 tone generators 

1 white noise generator 
5 octave total range 
Language: BASIC (built-in) 

6502 Machine Code 
I/O Ports: RS232C (modem) 

Expansion Port (cartridges 
with RAM, ROM, extra I/O) 
Cassette Port (CBM recorder) 
Serial Port (disk/printer) 
Audio/Video (TV or monitor) 
Game Port (Paddle, joystick, 
light pen) 

IEEE488: Optional accessory 

We at Commodore hope you enjoy working 
with the VIC 20 as much as we do.. .for more 
information contact your Commodore repre¬ 
sentative or write us in care of: 

VIC Product Team 

Commodore Business Machines Inc. 

Computer Systems Division 

681 Moore Road 

King of Prussia, PA 19406 


Commodore Business Machines Inc. 

Computer Systems Division 
681 Moore Road 
King of Prussia, PA 19406