Destination address for indexed mode DMA

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Anonymous
Not applicable

All: what is the address I am to use for the DMAC itself. Is the destination (the second TD) base address PERIPHERAL_BASE? What is the upper 16 bits (which register do I refer to)? The source of course would be SRAM (it would contain the new pointer). Dave Van Ess's latest video about the "Numerically controlled oscillator" uses Indexed DMA to carry out it's function...I'd just like to be able to replicate that behavior.

   

Thanks.

0 Likes
6 Replies
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

I'm not exactly sure, what you're talking about.

   

In the TD, the first address-parameter specifies the source and the second the destination lower address word.
The high address word given in the channel setup differs from PSoC3 to PSoC5 as outlined in the DMA-datasheet. While in PSoC3 the upper 16 bits of a pointer are containing a descriptor of the memory-area (there are some different ones) in PSoC5 you'll find true pointers. There are some macros defined to ease swithching between PSoC3 and 5 targets, have a look into the "System Reference Guide" (under Help -> Documentation ->...)

   

 

   

Bob

0 Likes
ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Some reference material -

   

 

   

http://www.cypress.com/?rID=37793

   

 

   

http://www.cypress.com/?rID=44335

   

 

   

Regards, Dana.

0 Likes
HeLi_263931
Level 8
Level 8
100 solutions authored 50 solutions authored 25 solutions authored

Indexed DMA is explained in (a little bit) more detail in the PSoC Sensei blog: www.cypress.com/ - there is also an example project there.

0 Likes
Anonymous
Not applicable

Hli: that was what I needed. I hadn't yet gone that far back into the Sensei blog, I didn't realize he had done that example. Thanks for the tip.

0 Likes
PIGO_1085426
Level 2
Level 2

Hi,

   

   Can anyone give example how to define indexed dma for Psoc 5 LP. I've tried do make it according Sensei blog and I have got no fault but it seems it doesn't work (lack of transfer data from source to destination).

0 Likes
PIGO_1085426
Level 2
Level 2

OK. I've done it.

   

Thanks.

0 Likes