📚 The SCREEN modes

Mode	Width X Height (Pixels)	Columns X Rows (Characters)	Screen Aspect	Font Height	Colour Mode	Bits Per Pixel
0	640 X 200	80 X 25	2.4	8	p16	4
1	320 X 200	40 X 25	1.2	8	p4	2
2	640 X 200	80 X 25	2.4	8	p2	1
7	320 X 200	40 X 25	1.2	8	p16	4
8	640 X 200	80 X 25	2.4	8	p16	4
9	640 X 350	80 X 25	480/350	14	p16	4
10	640 X 350	80 X 25	480/350	14	p2	1
11	640 X 480	80 X 30	1	16	p2	1
12	640 X 480	80 X 30	1	16	p16	4
13	320 X 200	40 X 25	1.2	8	p256	8
14	320 X 200	40 X 25	1	8	p256	8
15	320 X 200	40 X 25	2.4	8	p256	8
16	320 X 200	40 X 25	1.2	16	p256	8
17	320 X 200	40 X 25	1	16	p256	8
23	640 X 400	80 X 25	1.2	8	pRGB	24
24	640 X 400	80 X 25	1	8	pRGB	24
25	640 X 400	80 X 25	2.4	8	pRGB	24
26	640 X 400	80 X 25	1.2	16	pRGB	24
27	640 X 400	80 X 25	1	16	pRGB	24

Mode	Number of Colour Attributes	Bits Per Pixel
p2	2	1
p4	4	2
p16	16	4
p256	256	16
pRGB	undefined	24

• Note: p2, p4, p16 and p256: references to colour attributes allow "Colour attribute looping".

About Colour Attribute Looping

In BASIC Anywhere Machine, when working with colour modes that have colour attributes, we normally refer to those attributes as attributes zero to whatever maximum for that colour mode. (For example, attributes 0 to 15 in colour mode p16.)

When we refer to attributes with numbers outside of the range, BASIC Anywhere Machine loops around (treating the list of attributes like a circle.) So in colour mode p16, attribute 16 means attribute 0, and attribute 17 means attribute 1.

The same works in the other direction. In colour mode p16, attribute -1 means attribute 15, and attribute -2 means attribute 14.

The following statements and functions have been tested to make sure that works:

• COLOR
• CIRCLE
• LINE
• PAING
• PSET

p2 colours

0	Black
1	White

p4 colours

ID	RGB Colour Value
0	███RGB(0, 0, 0) ███RGB(0, 0, 0)
1	███RGB(0, 170, 170) ███RGB(0, 170, 170)
2	███RGB(170, 0, 170) ███RGB(170, 0, 170)
3	███RGB(170, 170, 170) ███RGB(170, 170, 170)

p16 colours

ID	RGB Colour Value
0	███RGB(0, 0, 0) ███RGB(0, 0, 0)
1	███RGB(0, 0, 170) ███RGB(0, 0, 170)
2	███RGB(0, 170, 0) ███RGB(0, 170, 0)
3	███RGB(0, 170, 170) ███RGB(0, 170, 170)
4	███RGB(170, 0, 0) ███RGB(170, 0, 0)
5	███RGB(170, 0, 170) ███RGB(170, 0, 170)
6	███RGB(170, 85, 0) ███RGB(170, 85, 0)
7	███RGB(170, 170, 170) ███RGB(170, 170, 170)
8	███RGB(85, 85, 85) ███RGB(85, 85, 85)
9	███RGB(85, 85, 255) ███RGB(85, 85, 255)
10	███RGB(85, 255, 85) ███RGB(85, 255, 85)
11	███RGB(85, 255, 255) ███RGB(85, 255, 255)
12	███RGB(255, 85, 85) ███RGB(255, 85, 85)
13	███RGB(255, 85, 255) ███RGB(255, 85, 255)
14	███RGB(255, 255, 85) ███RGB(255, 255, 85)
15	███RGB(255, 255, 255) ███RGB(255, 255, 255)

p256 colours

The BASIC Anywhere Machine default colours match "EGA" colours for attributes 0 to 63.

Attributes 64-254 are set to black, and attribute 255 is set to white.

ID	RGB Colour Value
0	███RGB(0, 0, 0) ███RGB(0, 0, 0)
1	███RGB(0, 0, 170) ███RGB(0, 0, 170)
2	███RGB(0, 170, 0) ███RGB(0, 170, 0)
3	███RGB(0, 170, 170) ███RGB(0, 170, 170)
4	███RGB(170, 0, 0) ███RGB(170, 0, 0)
5	███RGB(170, 0, 170) ███RGB(170, 0, 170)
6	███RGB(170, 170, 0) ███RGB(170, 170, 0)
7	███RGB(170, 170, 170) ███RGB(170, 170, 170)
8	███RGB(0, 0, 85) ███RGB(0, 0, 85)
9	███RGB(0, 0, 255) ███RGB(0, 0, 255)
10	███RGB(0, 170, 85) ███RGB(0, 170, 85)
11	███RGB(0, 170, 255) ███RGB(0, 170, 255)
12	███RGB(170, 0, 85) ███RGB(170, 0, 85)
13	███RGB(170, 0, 255) ███RGB(170, 0, 255)
14	███RGB(170, 170, 85) ███RGB(170, 170, 85)
15	███RGB(170, 170, 255) ███RGB(170, 170, 255)
16	███RGB(0, 85, 0) ███RGB(0, 85, 0)
17	███RGB(0, 85, 170) ███RGB(0, 85, 170)
18	███RGB(0, 255, 0) ███RGB(0, 255, 0)
19	███RGB(0, 255, 170) ███RGB(0, 255, 170)
20	███RGB(170, 85, 0) ███RGB(170, 85, 0)
21	███RGB(170, 85, 170) ███RGB(170, 85, 170)
22	███RGB(170, 255, 0) ███RGB(170, 255, 0)
23	███RGB(170, 255, 170) ███RGB(170, 255, 170)
24	███RGB(0, 85, 85) ███RGB(0, 85, 85)
25	███RGB(0, 85, 255) ███RGB(0, 85, 255)
26	███RGB(0, 255, 85) ███RGB(0, 255, 85)
27	███RGB(0, 255, 255) ███RGB(0, 255, 255)
28	███RGB(170, 85, 85) ███RGB(170, 85, 85)
29	███RGB(170, 85, 255) ███RGB(170, 85, 255)
30	███RGB(170, 255, 85) ███RGB(170, 255, 85)
31	███RGB(170, 255, 255) ███RGB(170, 255, 255)
32	███RGB(85, 0, 0) ███RGB(85, 0, 0)
33	███RGB(85, 0, 170) ███RGB(85, 0, 170)
34	███RGB(85, 170, 0) ███RGB(85, 170, 0)
35	███RGB(85, 170, 170) ███RGB(85, 170, 170)
36	███RGB(255, 0, 0) ███RGB(255, 0, 0)
37	███RGB(255, 0, 170) ███RGB(255, 0, 170)
38	███RGB(255, 170, 0) ███RGB(255, 170, 0)
39	███RGB(255, 170, 170) ███RGB(255, 170, 170)
40	███RGB(85, 0, 85) ███RGB(85, 0, 85)
41	███RGB(85, 0, 255) ███RGB(85, 0, 255)
42	███RGB(85, 170, 85) ███RGB(85, 170, 85)
43	███RGB(85, 170, 255) ███RGB(85, 170, 255)
44	███RGB(255, 0, 85) ███RGB(255, 0, 85)
45	███RGB(255, 0, 255) ███RGB(255, 0, 255)
46	███RGB(255, 170, 85) ███RGB(255, 170, 85)
47	███RGB(255, 170, 255) ███RGB(255, 170, 255)
48	███RGB(85, 85, 0) ███RGB(85, 85, 0)
49	███RGB(85, 85, 170) ███RGB(85, 85, 170)
50	███RGB(85, 255, 0) ███RGB(85, 255, 0)
51	███RGB(85, 255, 170) ███RGB(85, 255, 170)
52	███RGB(255, 85, 0) ███RGB(255, 85, 0)
53	███RGB(255, 85, 170) ███RGB(255, 85, 170)
54	███RGB(255, 255, 0) ███RGB(255, 255, 0)
55	███RGB(255, 255, 170) ███RGB(255, 255, 170)
56	███RGB(85, 85, 85) ███RGB(85, 85, 85)
57	███RGB(85, 85, 255) ███RGB(85, 85, 255)
58	███RGB(85, 255, 85) ███RGB(85, 255, 85)
59	███RGB(85, 255, 255) ███RGB(85, 255, 255)
60	███RGB(255, 85, 85) ███RGB(255, 85, 85)
61	███RGB(255, 85, 255) ███RGB(255, 85, 255)
62	███RGB(255, 255, 85) ███RGB(255, 255, 85)
63	███RGB(255, 255, 255) ███RGB(255, 255, 255)

pRGB colours

Well, maybe this should be called "Full RGB Range", as in the 16,777,216 colours that span the RGB colour model.

To specify a colour when in a screen mode that has the "undefined" colour scheme, this requires specifying the colour number with math related to RGB.

Each of the R, G, and B, values range from 0 to 255.

• color = R * (256 ^ 2) + G * (256 ^ 1) + B * (256 ^ 0)
• or: color = R * (256 ^ 2) + G * (256 ^ 1) + B * (256 ^ 0)