Just defined timing for each colour pattern as well as the quantity of 'color dots' on the screen.

Assuming that most CRT monitors have a 4:3 or 5:5 aspect ratio as well as the execution speed constraints, the amount of 'color dots' shall be 8 in horizontal and 6 in the vertical.

The ratio between color dots and spacing shall be 6:1 and the color dots shall be 12 cycles wide by 2 cycles of black screen.

In the picture below the lower part of the screen has stripes and intervals that correspond to the numbers presented above.