Nintendo 1504166 - Game Boy Advance SP Edition Console, Programming Manual

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AGB Programming Manual Rendering Functions
©1999 - 2001 Nintendo of America Inc.
60
D.C.N. AGB-06-0001-002B4
6.3.2 Character Data Mapping
With OBJ character data, the basic character is 8 x 8 dots, and characters
between 8 x 8 and 64 x 64 dots can be handled (total of 12 types). The
base address of OBJ character data is a fixed VRAM base address. The
OBJ character data capacity allocated is either 32 Kbytes or 16 Kbytes,
depending on the BG mode (see 5.1.2 "VRAM Memory Map").
There are 2 types of mapping to the character area, and they can be
specified in bit [d06] of the DISPCNT register.
OBJ is managed by character numbers that are divided by 32 bytes
starting with OBJ character database address. 32 bytes is the required
capacity to define 1 basic character of 16 colors x 16 palettes. 64 bytes is
the required capacity to define 1 basic character of 256 colors x 1 palette.
1) VRAM 2-Dimensional Mapping for OBJ Characters
Setting the DISPCNT register bit [d06] to 0 results in the 2-dimensional
mapping mode shown in the following figure.
000
H
001
H
002
H
003
H
020
H
021
H
022
H
044
H
040
H
041
H
042
H
043
H
004
H
024
H
025
H
005
H
023
H
045
H
060
H
061
H
062
H
063
H
080
H
081
H
082
H
0A4
H
0A0
H
0A1
H
0A2
H
0A3
H
064
H
084
H
085
H
065
H
083
H
0A5
H
0C0
H
0C1
H
0C2
H
0C3
H
0E0
H
0E1
H
0E2
H
104
H
100
H
101
H
102
H
103
H
0C4
H
0E4
H
0E5
H
0C5
H
0E3
H
105
H
120
H
121
H
122
H
123
H
140
H
141
H
142
H
164
H
160
H
161
H
162
H
163
H
124
H
144
H
145
H
125
H
143
H
165
H
006
H
047
H
046
H
028
H
008
H
026
H
048
H
087
H
066
H
0A7
H
0A6
H
067
H
088
H
068
H
086
H
0A8
H
0E7
H
0C6
H
107
H
106
H
0C7
H
0E8
H
0C8
H
0E6
H
108
H
147
H
126
H
167
H
166
H
127
H
148
H
128
H
146
H
168
H
01B
H
05B
H
03B
H
07B
H
01D
H
01C
H
01E
H
05D
H
03C
H
07D
H
07C
H
05E
H
05C
H
07E
H
01F
H
05F
H
07F
H
09B
H
0DB
H
0BB
H
0FB
H
09D
H
09C
H
09E
H
0DD
H
0BC
H
0FD
H
0FC
H
0BD
H
0DE
H
0BE
H
0DC
H
0FE
H
09F
H
0DF
H
0BF
H
0FF
H
11B
H
15B
H
13B
H
17B
H
11D
H
11C
H
11E
H
15D
H
13C
H
17D
H
17C
H
13D
H
15E
H
13E
H
15C
H
17E
H
11F
H
15F
H
13F
H
17F
H
32x32 dots
(16 colors/16 palettes)
64x64 dots
(16 colors/16 palettes)
8x16 dots
(16 colors/16 palettes)
16x16 dots
(256 colors/1 palette)
Basic Character
8x8 dots
(16 colors/16 palettes)
Character mapping area (character no.in hexadecimal notation)
Character name
027
H
03D
H
03E
H
03F
H
007
H