Commodore 128 System Manual page 105

GRAPHIC <mode [,c] [,s] / CLR>
where mode is a digit between 0 and 5, c is either a 0 or 1 and s
is a value between 0 and 25. Figure 6-4 shows the values
corresponding to the graphic modes.
Mode
0
1
2
3
4
5
The parameter CLR stands for CLEAR. Figure 6-5 explains the
values associated with CLEAR.
C Value
0
1
When you first run your program, you will want to clear the
graphics screen for the first time, so set c equal to 1 in the
GRAPHIC command. If you run it a second time, you may want to
leave your picture on the screen, instead of drawing it all over
again, ln this case, set c equal to 0.
The s parameter specifies where the start of the text screen in
split screen mode is to begin at the line after the specified line
number. If you omit the s parameter and select a split-screen
graphic mode (2 or 4), the text screen portion is displayed in rows
20 through 25; the rest of the screen is bit mapped. The s
parameter allows you to change the starting line of the text
screen to any line on the screen, ranging from 1 through 25. A
zero as the s parameter indicates the screen is not split, and is all
text.
The final GRAPHIC command parameter is CLR. When you first
issue a bit map graphic command, the Commodore 128 allocates
Description
40-column standard text
Standard bit map
Standard bit map (split screen)
Multicolor bit map
Multicolor bit map (split screen)
80-column text
Figure 6-4. Graphic Modes
Do not clear the graphics screen
Clear the graphics screen
Figure 6-5. CLEAR Parameters
Description
6-7