0_100_1 0_2 0_3 0_4 0_5 0_6 0_7 0_8 0_9 0_A 0_B 0_C 0_D 0_E 0_F
1_101_1 1_2 1_3 1_4 1_5 1_6 1_7 1_8 1_9 1_A 1_B 1_C 1_D 1_E 1_F
2_102_1 2_2 2_3 2_4 2_5 2_6 2_7 2_8 2_9 2_A 2_B 2_C 2_D 2_E 2_F
3_103_1 3_2 3_3 3_4 3_5 3_6 3_7 3_8 3_9 3_A 3_B 3_C 3_D 3_E 3_F
4_104_1 4_2 4_3 4_4 4_5 4_6 4_7 4_8 4_9 4_A 4_B 4_C 4_D 4_E 4_F
5_105_1 5_2 5_3 5_4 5_5 5_6 5_7 5_8 5_9 5_A 5_B 5_C 5_D 5_E 5_F
6_106_1 6_2 6_3 6_4 6_5 6_6 6_7 6_8 6_9 6_A 6_B 6_C 6_D 6_E 6_F
7_107_1 7_2 7_3 7_4 7_5 7_6 7_7 7_8 7_9 7_A 7_B 7_C 7_D 7_E 7_F
8_108_1 8_2 8_3 8_4 8_5 8_6 8_7 8_8 8_9 8_A 8_B 8_C 8_D 8_E 8_F
9_109_1 9_2 9_3 9_4 9_5 9_6 9_7 9_8 9_9 9_A 9_B 9_C 9_D 9_E 9_F
A_10A_1 A_2 A_3 A_4 A_5 A_6 A_7 A_8 A_9 A_A A_B A_C A_D A_E A_F
B_10B_1 B_2 B_3 B_4 B_5 B_6 B_7 B_8 B_9 B_A B_B B_C B_D B_E B_F
0
479
0
6
3
9
Channel Source
Address (SRC)
Channel Destination
Address (DST)
www.ti.com
Functional Description
(b) Channel Options Parameter (OPT) Content
31 30 28 27 24 23 22 21 20 19 18 17 16
0 000 0000 0 0 0 1 00 00
PRIV Reserved PRIVID ITCCHEN TCCHEN ITCINTEN TCINTEN Reserved TCC
15 12 11 10 8 7 4 3 2 1 0
0000 0 000 0000 1 0 0 0
TCC TCCMOD FWID Reserved STATIC SYNCDIM DAM SAM
11.3.19.2 Subframe Extraction Example
The EDMA3 can efficiently extract a small frame of data from a larger frame of data. By performing a 2D-
to-1D transfer, the EDMA3 retrieves a portion of data for the CPU to process. In this example, a
640 × 480-pixel frame of video data is stored in external memory. Each pixel is represented by a 16-bit
halfword. The CPU extracts a 16 × 12-pixel subframe of the image for processing. To facilitate more
efficient processing time by the CPU, the EDMA3 places the subframe in internal L2 SRAM. Figure 11-24
shows the transfer of a subframe from external memory to L2. Figure 11-25 shows the parameters for this
transfer.
The same PaRAM entry options are used for QDMA channels, as well as DMA channels. The STATIC bit
in OPT is set to prevent linking. For successive transfers, only changed parameters need to be
programmed before triggering the channel.
Figure 11-24. Subframe Extraction Example
Figure 11-25. Subframe Extraction Example PaRAM Configuration
(a) EDMA Parameters
Parameter Contents Parameter
0010 000Ch Channel Options Parameter (OPT)
Channel Source Address (SRC) Channel Source Address (SRC)
000Ch 0020h Count for 2nd Dimension (BCNT) Count for 1st Dimension (ACNT)
Channel Destination Address (DST) Channel Destination Address (DST)
0020h 0500h Destination BCNT Index (DSTBIDX) Source BCNT Index (SRCBIDX)
0000h FFFFh BCNT Reload (BCNTRLD) Link Address (LINK)
0000h 0000h Destination CCNT Index (DSTCIDX) Source CCNT Index (SRCCIDX)
0000h 0001h Reserved Count for 3rd Dimension (CCNT)
921
SPRUH73H–October 2011–Revised April 2013 Enhanced Direct Memory Access (EDMA)
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