APPENDIX FIVE



ignored in this command and is instead set with SETCOLOR 1 --
where the color is ignored. You can use SETCOLOR to change the
colors of the text and the background as below:

GRAPHICS 0                    SETCOLOR     Register
Character luminance              1           709
Background                       2           710
Border (BAK)                     4           712

GRAPHICS 1 and 2              SETCOLOR     Register
Uppercase and numbers            0           708
Lowercase characters             1           709
Inverse uppercase                2           710
Inverse lowercase                3           711
Background, border               4           712

When you want to draw or fill an area in modes three to eight, you must
use the proper COLOR statement for the SETCOLOR register:

GRAPHICS 3, 5, 7           SETCOLOR       COLOR   Register
Four color modes
Graphics point or             0             1       708
fill area                     1             2       709
                              2             3       710
Background, border            4             0       712

GRAPHICS 4, 6              SETCOLOR       COLOR   Register
Two color modes
Graphics point                0             1       708
Background, border            4             0       712

GRAPHICS 8                 SETCOLOR       COLOR   Register
One color, two luminances
Graphics luminance            1             1       709
Background color              2             0       710
Border                        4            --       712

It's awkward, but not difficult to use. You will have to refer to this chart
or the chart on page 53 of your BASIC Reference Manual until you get
the hang of it. Remember to precede any COLOR statement with a
SETCOLOR somewhere in your program and to precede a DRAW or
XIO 18 with a COLOR or the computer will use the previously
designated register.

The GTIA chip confuses things somewhat: in GRAPHICS 10, register
704 stores the background color while 712 is used as a normal color
register. This means you must change it with a POKE rather than a
SETCOLOR statement. However, in the two other GTIA modes (GR.9
and GR. 11), you still use location 712, SETCOLOR 4, for the
background; see the examples of GTIA modes at location 623.