Changes
CRTC
,/* Screen size */
We can calculate the screen size in words by multiplying R1 x R6 x (R9+1). And then multiplying the result by 2 to have the screen size in bytes.
With the default CRTC values, we obtain 40x25x40 x 25 x (7+1)x2 x 2 = 16000 bytes.
So we can observe that only part of the 16384 bytes (=16KB) page of VRAM is actually displayed on screen.
