13.4.9 Addressing Modes
Following each transfer, the DMAxSRC and DMAxDST registers may be automatically updated by the channel. This potentially allows the channel to move data between multiple locations without the need for user intervention. Automatic address updating is controlled by the SAMODEx and DAMODEx bits (DMAxCH[15:14] and [13:12]).
The combination of the different address update options (fixed, increment or decrement)
provides four supported addressing modes:
- Fixed to Fixed
- Fixed to Block
- Block to Fixed
- Block to Block
Table 13-23 shows the address modes and the various SAMODEx and DAMODEx combinations.
| Mode(1) | SAMODE[1:0] | DAMODE[1:0] |
|---|---|---|
| Fixed to Fixed | 00 | 00 |
| Fixed to Block (Address Increment) | 00 | 01 |
| Fixed to Block (Address Decrement) | 00 | 10 |
| Block to Fixed (Address Increment) | 01 | 00 |
| Block to Fixed (Address Decrement) | 10 | 00 |
| Block to Block (Address Increment) | 01 | 01 |
| Block to Block (Address Decrement) | 10 | 10 |
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Note:
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