Pixel Data; Pixel Data Address Mapping For The Lcd Screen; Figure 38 - 32,768-Color Simultaneous Display Format; Figure 39 - 256-Color Display Format - Nintendo GAME BOY ADVANCE Programming Manual

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6.2.3

Pixel Data

In the bitmap modes, only the amount of pixel data corresponding to the size of the display screen can be
stored in VRAM. Available bitmap modes allow the simultaneous display of 32,768 colors (BG modes 3
and 5) and the display of 256 of the 32,768 colors (BG mode 4). The format of the data in the frame buffer
differs between the modes as described below.
6.2.3.1 32,768-Color Simultaneous Display Format (BG Modes 3 and 5)
• Palette RAM is not referenced.
• Each pixel uses a half-word.

Figure 38 - 32,768-Color Simultaneous Display Format

15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
B4 B3 B2 B1 B0 G4 G3 G2 G1 G0 R4 R3 R2 R1 R0
6.2.3.2 256-Color (of 32,768) Display Format (BG Mode 4)
• Palette RAM color data (256 of the 32,768 colors storable) are referenced.
• Each pixel uses 1 byte.
6.2.4

Pixel Data Address Mapping for the LCD Screen

The different address mappings for the different BG modes are shown below.
The frame buffer (VRAM) starts at address 06000000h. Thus, to see the addresses used by the CPU, add
06000000h to the addresses shown below.
6.2.4.1 BG Mode 3 (32,768 colors, 240X160 pixels, 1 frame buffer)
Because there is a single frame buffer, this mode is used mainly for still images. However, it enables
32,768 colors to be displayed simultaneously over the full screen.
Table 10 - BG Mode 3
0 1
0 0h 2h
1 1E0h 1E2h
2 3C0h 3C2h
3 5A0h 5A2h
AGB-06-0001-002-B13
Released: May 27, 2005
Game Boy Advance Programming Manual
Blue

Figure 39 - 256-Color Display Format

07 06 05 04 03 02 01 00
Color No.
2 3 4
4h 6h 8h
1E4h 1E6h 1E8h
3C4h 3C6h 3C8h
5A4h 5A6h 5A8h
Green Red
236 237
1D8h 1Dah
3B8h 3Bah
598h 59Ah
778h 77Ah
© 1999-2005 NINTENDO
May 25, 2005
238 239
1DCh 1DEh
3BCh 3BEh
59Ch 59Eh
77Ch 77Eh