AGB Programming Manual
DMA Transfer
©1999 - 2001 Nintendo of America Inc.
109
D.C.N. AGB-06-0001-002B4
12.1 DMA 0
DMA 0 allows different areas of internal memory in the main unit to access one
another. It has the highest priority of the DMA channels.
1) Source Address
Specifies the source address using 27 bits.
The area 00000000h-07FFFFFFh (internal memory area of main unit) can
be specified.
15 14
13
12 11
10
09 08
07
06
05 04
03
02 01
00
DMA0
SAD_L
0B0h
0000h
W
Address
Register
Attributes
Initial Value
15 14
13
12 11
10
09 08
07
06
05 04
03
02 01
00
DMA0
SAD_H
0B2h
0000h
W
Address
Register
Attributes
Initial Value
2) Destination Address
Specifies the destination address using 27 bits.
The area 00000000h-07FFFFFFh (internal memory area of main unit) can
be specified.
15 14
13
12 11
10
09 08
07
06
05 04
03
02 01
00
DMA0
DAD_L
0B4h
0000h
W
Address
Register
Attributes
Initial Value
15 14
13
12 11
10
09 08
07
06
05 04
03
02 01
00
DMA0
DAD_H
0B6h
0000h
W
Address
Register
Attributes Initial Value
3) Word Count
Specifies the number of bytes transferred by DMA0, using 14 bits. The
number can be specified in the range 0001h~3FFFh~0000h (when 0000h
is set, 4000h bytes are transferred).
Thus, in 16-bit data transfer mode, up to 4000h x 2=8000h bytes can be
transferred, and in 32-bit data transfer mode, up to 4000h x 4=10000h
bytes can be transferred.
15 14
13
12 11
10
09 08
07
06
05 04
03
02 01
00
DMA0
CNT_L
0B8h
0000h
W
Address
Register
Attributes
Initial Value