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關於Am335x McASP-EDMA的問題

你好!
關於Am335x TRM (SPRUH73J) 的EDMA內容疑問:

page 1280,  ( 參考 spru966c- TMS320c645x EDMA3,sprugs5a- EDMA3 guide)

  “ 11.3.19.4.3.1 Receive Channel

…….. 

there are two data channels being serviced, A and B, they are to be located separately within the L2 SRAM. “

 Channel Destination Address (DST)= 80 0000h,(參考sprugs5a- page 3-11)

Stream A Destination Address在 80 0000h,(參考sprugs5a- page 3-11)

Stream B Destination Address在 80 0080h;(參考sprugs5a- page 3-11)

ACNT=1, BCNT=80h, DSTBIXD=1, SRCBIXD=0;

 問題:

1. a. DSTBIXD=1,EDMA3為何知道要將Stream B放到(Stream A)DST+80h處;

    b. 如果再加一個data channel, Stream C;也會自動將Stream C放到DST+80h+80h處嗎?

    c. 若ACNT=2,會自動將Stream B放到DST+80h*2處嗎?

    d. 以前McBSP –DMA 好像不是這樣!

       這是McASP -EDMA3 獨特功能嗎?當EDMA3判別來源是McASP TDM時,會自動將不同的data channel stream放到不同的DST?(+ BCNT* ACNT)

   這種認知對嗎?還是哪裡沒看懂?或者這個範例寫錯了?

 2. McASP的RSR -> memory 時, source address 不變;

   範例中, OPT的「SAM=0, SRCBIXD=0」若改用「SAM=1」,這二種配置的結果相同嗎?

 3. am335x 的L2 SRAM address定義在什麼地方?沒看到相關說明。

    spru966c和sprugs5a的範例,L2 SRAM= 80 0000h, 是指TMS320c645x相關DSP 的L2 SRAM address, 並不適用於am335x。

麻煩你們,  謝謝 !