Commodore Plus 4 - Page 214

202 Programming Graphics
You need to decide where in RAM your characters will be stored. They must be
stored in an area of RAM not otherwise used by your program. (See Chapter 5 on
moving BASIC and where BASIC programs reside.) Also, the graphics chip
always considers a 1K (1024-byte) section of memory (room for 128 characters) to
be its current character set. Therefore, your custom character set must begin on a
IK boundary. The boundary used is controlled by the upper 6 bits of 65299
($FF13). To specify the location of your character set, you can use the following
BASIC line:
P0KE65299,(PEEK(65S99)AlTO3)0Rx
where the value of x is determined from Table 4-2.
Table 4-2. Custom Character Set Locations
Hex
$00
$04
$08
$0C
$10
$14
$18
$1C
$20
$24
$28
$2C
$30
$34
$38
$3C
$40
$44
$48
$4C
$50
$54
$58
$5C
X
Dec
0
4
8
12
16
20
24
28
32
36
40
44
48
52
56
60
64
68
72
76
80
84
88
92
Characters
Hex
$0000
$0400
$0800
$0C00
$1000
$1400
$1800
$lC00
$2000
$2400
$2800
$2C00
$3000
$3400
$3800
$3C00
$4000
$4400
$4800
$4C00
$5000
$5400
$5800
$5C00
Decimal
0
1024
2048
3072
4096
5120
6144
7168
8192
9216
10240
11264
12288
13312
14336
15360
16384
17408
18432
19456
20480
21504
22528
23552
Hex
$60
$64
$68
$6C
$70
$74
$78
$7C
$80
$84
$88
$8C
$90
$94
$98
$9C
$A0
$A4
$A8
$AC
$B0
$B4
$B8
$BC
X
Dec
96
100
104
108
112
116
120
124
128
130
134
138
142
146
150
154
160
164
168
172
176
180
184
188
Characters
Hex
$6000
$6400
$6800
$6C00
$7000
$7400
$7800
$7C00
$8000
$8400
$8800
$8C00
$9000
$9400
$9800
$9C00
$A000
$A400
$A800
$AC00
$B000
$B400
$B800
$BC00
Decimal
24576
25600
26624
27648
28672
29696
30720
31744
32768
33792
34816
35840
36864
37888
38912
39936
40960
41984
43008
44032
45056
46080
47104
48128
Hex
$C0
$C4
$C8
$cc
$D0
$D4
$D8
$DC
$E0
$E4
$E8
$EC
$F0
$F4
$F8
$FC
X
Dec
192
196
200
204
208
212
216
220
224
228
232
236
240
244
248
252
Characters
Hex
$C000
$C400
$C800
$CC00
$D000
$D400
$D800
$DC00
$E000
$E400
$E800
$EC00
$F000
$F400
$F800
$FC00
Decimal
49152
50176
51200
52224
53248
54272
55296
56320
57344
58368
59392
60416
61440
62464
63488
64512