Datasheet

466
SAM9G25 [DATASHEET]
11032C–ATARM–25-Jan-13
transfer match described in Row 1 of Table 31-3 on page 462. The DMAC then knows that the previous buffer
transferred was the last buffer in the DMAC transfer. The DMAC transfer might look like that shown in Figure 31-6
on page 466.
Figure 31-6. Multi-buffer with Linked List Address for Source and Destination
If the user needs to execute a DMAC transfer where the source and destination address are contiguous but the amount
of data to be transferred is greater than the maximum buffer size DMAC_CTRLAx.BTSIZE, then this can be achieved
using the type of multi-buffer transfer as shown in Figure 31-7 on page 466.
Figure 31-7. Multi-buffer with Linked Address for Source and Destination Buffers are Contiguous
SADDR(2)
SADDR(1)
SADDR(0)
DADDR(2)
DADDR(1)
DADDR(0)
Buffer 2
Buffer 1
Buffer 0
Buffer 0
Buffer 1
Buffer 2
Address of
Source Layer
Address of
Destination Layer
Source Buffers Destination Buffers
SADDR(2)
SADDR(1)
SADDR(0)
DADDR(2)
DADDR(1)
DADDR(0)
Buffer 2
Buffer 1
Buffer 0
Buffer 0
Buffer 1
Buffer 2
Address of
Source Layer
Address of
Destination Layer
Source Buffers
Destination Buffers
SADDR(3)
Buffer 2
DADDR(3)
Buffer 2