Array 0 Array 1 Array 2 Array 3
Each array submit
as one TR
Array 0 Array 3Array 1 Array 2
(SRC|DST)
BIDX
(SRC|DST)
BIDX
(SRC|DST)
BIDX
(SRC|DST)
BIDX
(SRC|DST)
BIDX
(SRC|DST)
BIDX
(SRC|DST)
CIDX
(SRC|DST)
BIDX
Array 0
Array 3
(SRC|DST)
Array 1
BIDX BIDX
(SRC|DST)
Array 2
(SRC|DST)
CIDX
Frame 0
Frame 1
Frame 2
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Enhanced Direct Memory Access (EDMA3) Controller
16.2.2.1 A-Synchronized Transfers
In an A-synchronized transfer, each EDMA3 sync event initiates the transfer of the 1st dimension of ACNT
bytes, or one array of ACNT bytes. In other words, each event/TR packet conveys the transfer information
for one array only. Thus, BCNT × CCNT events are needed to completely service a PaRAM set.
Arrays are always separated by SRCBIDX and DSTBIDX, as shown in Figure 16-5, where the start
address of Array N is equal to the start address of Array N – 1 plus source (SRCBIDX) or destination
(DSTBIDX).
Frames are always separated by SRCCIDX and DSTCIDX. For A-synchronized transfers, after the frame
is exhausted, the address is updated by adding SRCCIDX/DSTCIDX to the beginning address of the last
array in the frame. As in Figure 16-5, SRCCIDX/DSTCIDX is the difference between the start of Frame 0
Array 3 to the start of Frame 1 Array 0.
Figure 16-5 shows an A-synchronized transfer of 3 (CCNT) frames of 4 (BCNT) arrays of n (ACNT) bytes.
In this example, a total of 12 sync events (BCNT × CCNT) exhaust a PaRAM set. See Section 16.2.3.6 for
details on parameter set updates.
Figure 16-5. A-Synchronized Transfers (ACNT = n, BCNT = 4, CCNT = 3)
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