Nintendo 1504166 Programming Manual - Page 116

DMA1, 2CNT_H [d07] Destination Address Control Flag

Page 116 highlights

AGB Programming Manual DMA Transfer DMA(1,2)CNT_H [d09] DMA Repeat With the DMA repeat function set to ON, if V-blanking or H-blanking intervals are selected as the timing of DMA startup, DMA is restarted when the next startup condition occurs (a V-blank or H-blank). In this mode, restarting will continue as long as the DMA enable flag is not set to 0. When the DMA repeat function is set to OFF, DMA halts as soon as the amount of data specified by the value in the word-count register has been transferred. Set this bit to 1 in direct-sound FIFO transfer mode. DMA(1,2)CNT_H [d08] Source Address Control Flag Control of the source address is specified after each DMA transfer. A setting of 00 causes an increment. A setting of 01 causes a decrement. A setting of 10 causes it to be fixed. 11 is a prohibited code. When the Game Pak Bus has been set to the source address, make sure you select increment. DMA(1,2)CNT_H [d07] Destination Address Control Flag Control of the destination address is specified after each DMA transfer. A setting of 00 causes an increment. A setting of 01 causes a decrement. A setting of 10 causes it to be fixed. A setting of 11 causes an increment to be carried out and then a reload(returned to setting at start of transfer) is done after every transfer is completed. However, when in direct sound FIFO transfer mode, the destination address is fixed and unrelated to the setting. ©1999 - 2001 Nintendo of America Inc. 116 D.C.N. AGB-06-0001-002B4

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171

AGB Programming Manual
DMA Transfer
©1999 - 2001 Nintendo of America Inc.
116
D.C.N. AGB-06-0001-002B4
DMA(1,2)CNT_H [d09] DMA Repeat
With the DMA repeat function set to ON, if V-blanking or H-blanking
intervals are selected as the timing of DMA startup, DMA is restarted when
the next startup condition occurs (a V-blank or H-blank).
In this mode,
restarting will continue as long as the DMA enable flag is not set to 0.
When the DMA repeat function is set to OFF, DMA halts as soon as the
amount of data specified by the value in the word-count register has been
transferred.
Set this bit to 1 in direct-sound FIFO transfer mode.
DMA(1,2)CNT_H [d08] Source Address Control Flag
Control of the source address is specified after each DMA transfer.
A setting of 00 causes an increment.
A setting of 01 causes a decrement.
A setting of 10 causes it to be fixed.
11 is a prohibited code.
When the Game Pak Bus has been set to the source address, make sure
you select increment.
DMA(1,2)CNT_H [d07] Destination Address Control Flag
Control of the destination address is specified after each DMA transfer.
A setting of 00 causes an increment.
A setting of 01 causes a decrement.
A setting of 10 causes it to be fixed.
A setting of 11 causes an increment to be carried out and then a
reload(returned to setting at start of transfer) is done after every transfer is
completed.
However, when in direct sound FIFO transfer mode, the destination address is
fixed and unrelated to the setting.