mode 128, you can change the range of colours available, i.e. instead of black

and white you could choose red and yellow.

However, the numbers used in GCOL and COLOUR commands produce

different effects in different modes and the colour displayed depends upon two

sets of information.

Colour number assignments                            Actual Colours

in Mode 0 (128)

              0                                        0 Black

                                                       1 Red

                                                       2 Green

                                                       3 Yellow

                                                       4 Blue

                                                       5 Magenta

                                                       6 Cyan

            1                                          7 White

                                                       8 Black/White

                                                       9 Red/Cyan

                                                       10 Green/Magenta

                                                       11 Yellow/Blue

                                                       12 Blue/Yellow

                                                       13 Magenta/Green

                                                       14 Cyan/Red

                                                       15 White/Black

The list on the right shows what are called the actual colour numbers of the 16

pure colours. This list never changes and is the same for every mode. The way

the colour numbers for the mode are associated with this actual colour list can

be varied by using the VDU 19 command. For example, type:

MODE 128

VDU 19,0,1,0,0,0

This instantly changes the normal black background colour to red.

C 60