AGB Programming Manual
DMA Transfer
©1999 - 2001 Nintendo of America Inc.
117
D.C.N. AGB-06-0001-002B4
12.3 DMA 3
DMA 3 provides memory access between the Game Pak bus and internal memory of
the main unit, or between different areas of internal memory of the main unit.
1) Source Address
Specifies the source address using 28 bits.
The area 00000000h-0FFFFFFFh (internal memory of main unit and Game
Pak memory area) can be specified.
15
14
13 12
11
10 09
08
07 06
05
04 03
02
01 00
DMA3SAD_L
0D4h
0000h
W
Address
Register
Attributes
Initial
Value
15
14
13 12
11
10 09
08
07 06
05
04 03
02
01 00
DMA3SAD_H
0D6h
0000h
W
Address
Register
Attributes
Initial
Value
2) Destination Address
Specifies the destination address using 28 bits.
The area 00000000h-0FFFFFFFh (internal memory area of main unit and
Game Pak memory area) can be specified.
15
14 13
12
11
10 09
08
07 06
05
04 03
02
01 00
DMA3DAD_L
0D8h
0000h
W
Address
Register
Attributes
Initial
Value
15
14 13
12
11
10 09
08
07 06
05
04 03
02
01 00
DMA3DAD_H
0DAh
0000h
W
Address
Register
Attributes
Initial
Value
3) Word Count
Specifies the number of bytes transferred by DMA 3, using 16 bits. The
number can be specified in the range 0001h~FFFFh~0000h (when 0000h
is set, 10000h bytes are transferred).
Thus, in 16-bit data transfer mode, up to 10000h x 2=20000h bytes can be
transferred, and in 32-bit data transfer mode, up to 10000h x 4=40000h
bytes can be transferred.
15
14 13
12
11
10 09
08
07 06
05
04 03
02
01 00
DMA3CNT_L
0DCh
0000h
W
Address
Register
Attributes
Initial
Value