Nintendo 1504166 - Game Boy Advance SP Edition Console Programming Manual page 115

AGB Programming Manual
DMA(1,2)CNT_H [d14] Interrupt Request Enable Flag
Enables an interrupt request to be generated when DMA transfer of the
specified word count has been completed.
No request is generated with a setting of 0; a request is generated with a
setting of 1.
DMA(1,2)CNT_H [d13 - 12] DMA Startup Timing
The timing of the DMA transfer can be selected from the following options.
Setting
00
01
10
11
DMA(1,2)CNT_H [d10] DMA Transfer Type
Sets the bit length of the transfer data.
With a setting of 0, the data are transferred by DMA in 16-bit (half-word)
units. With a setting of 1, the data are transferred by DMA in 32-bit (word)
units.
In direct-sound FIFO transfer mode, the data are transferred in 32-bit units.
©1999 - 2001 Nintendo of America Inc.
Start Immediately
Start During a V-blanking interval
Starts at the beginning of a V-blanking interval (approximately
4.993 ms).
Start During a H-blanking interval
Starts at the beginning of a H-blanking interval (approximately
16.212 s).
If this accompanies OAM access, the H-blanking interval must
first be freed of OBJ display hardware processing periods. (See
"Chapter 5, Image System".)
Start When Request Generated by Direct-Sound
FIFO
Starts when a request is received form direct-sound
FIFO. Specify sound FIFO as the destination address.
Also, set the DMA repeat function [d09] to ON.
115
DMA Startup Timing
DMA Transfer
D.C.N. AGB-06-0001-002B4