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DMA mode, address update, activation factor selection register

This register specifies the DMA mode (direct or indirect mode), address update (holding or updating set values), and activation factor selection. Figure 3.10 shows the details of this register. When the DMA is operating, the register at that level is write-protected. 

 Figure 3.10 Level 2-0 DMA mode, address update, activation factor selection register
(Register: D0MD, D1MD, D2MD) Initial value 00000007H

DMA mode bit (Fig. 3.10, 1 [bit 24])
DxMOD [x = 2-0] (W) DMA level 2-0 MODe bit
Determines the DMA mode. 0 means direct mode, 1 means indirect mode.

Read address update bit (2 [bit 16] in Figure 3.10)
DxRUP [x = 2-0] (W) DMA level 2-0 Read address renewal UP bit
Decide whether to retain or update the setting value for the read address. 0 means hold, 1 means update. For details of operation, refer to the specific usage example in Section 2.1 “DMA Transfer”.

Write address update bit (3 [bit 8] in Figure 3.10)
DxWUP [x = 2-0] (W) DMA level 2-0 Write address renewa UP bit
Decide whether to keep or update the setting value for the write address. 0 means hold, 1 means update. For details of operation, refer to the specific usage example in Section 2.1 “DMA Transfer”.

DMA activation factor selection bits (4 to 6 [bits 2 to 0] in Figure 3.10)
DxFT2-0 [x = 2-0] (W) DMA level 2-0 starting FacTor bit2-0
DMA is activated by setting the DMA enable bit and receiving the external signal selected by the activation factor selection bit. However, when the activation factor bit is 111B, DMA is activated by setting the DMA activation bit.

Table 3.4 Startup factor details 
 Set permission bit and V-blank-IN signal reception  
 Set permission bit and V-blank-OUT signal reception  
 Set permission bit and receive H-blank-IN signal  
 Set permission bit and receive timer 0 signal  
 Set permission bit and receive timer 1 signal  
 Set permission bit and sound-Req signal reception  
 Set permission bit and receive sprite drawing end signal  
 Set permission bits and DMA start bit 

 Start factor bit (x = 2−0) 
 Start factor 
DxFT2
DxFT1
DxFT0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1

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