Question about TMS320C6747 DMA Event

wanseung yang

Intellectual 350 points

Other Parts Discussed in Thread: TMS320C6747, OMAPL138

Hi there

I have a Question about TMS320C6747 DMA Event

First of All, I'm using TMS320C6747 EVM(OMAP-L137) and i have runned evmc6747_dsp.gel

I want to transfer a data to EMIFA via DMA and it must be synchronized with a Clock(external source)

it means i want to transfer a data to EMIFA at every single rising edge of the Clock

So, i'm using DMA with event triggered mode, and the event source is a rising edge of GPIO

But... if the Frequency of the Clock is more than 4.8 MHz, DMA Block doesn't transfer a data at every single rising edge

after generated many rising edge, DMA Transfer a data to EMIF

Are there a limit about data rate or Time interval between events?

over 9 years ago

0 Shankari G over 9 years ago

TI__Mastermind 43955 points

Hi Wanseung yang,

For C6747/OMAPL137, you can refer to the sample EDMA driver examples of the "quickStartOMAPL1x_rCSL " package.

Once you install this package, you will find the example driver at "~\ti\quickStartOMAPL1x_rCSL\OMAPL1x\rCSL_examples\evmOMAPL137\DSP_examples\edma"

EDMA_event_trig_dspL137

EDMA_manual_trig_dspL137

EDMA_ping_pong_dspL137

EDMA_self_chain_dspL137

And also let us know what device is connected to through EMIFA? Is it NAND?

0 wanseung yang over 9 years ago in reply to Shankari G

Intellectual 350 points

Hi Shankari

Thanks for your quick response

i already checked EDMA_event_trig_dspL137.

But as you know the period of the this example is too low speed

don't you think?

anyway

i connected a DA Converter through EMIFA for 13 bit data access

sometimes i connect a logic analyzer to observe the output of the EMIFA

Regards,
Wanseung Yang

0 Shankari G over 9 years ago in reply to wanseung yang

TI__Mastermind 43955 points

Hi wanseung yang,

Either we may have to optimize/improve upon this example for higher speed or Look for examples of OMAPL138 ( Starterware ) and port it to OMAPL137.

0 wanseung yang over 9 years ago in reply to Shankari G

Intellectual 350 points

HI Shankari

->Either we may have to optimize/improve upon this example for higher speed or Look for examples of OMAPL138 ( Starterware ) and port it to OMAPL137.

you mean the EDMA_event_trig_dspL137 or EDMA_event_trig_dspL137?

if so, above example doesn't fit with my application.

Could you advice me more concretely?

in my post first question, did not i made myself clear?

Regards,
Wanseung Yang

0 Shankari G over 9 years ago in reply to wanseung yang

TI__Mastermind 43955 points

Hi Wanseung,

Please check whether the "edma test.c" example which is part of OMAPL138 starterware can be utilised for your testing.

This example is for OMAPL138( DSP core- C6748) . If you see that this example can fullfill your requirement, you can consider porting it for C6747.

Starterware download page: processors.wiki.ti.com/.../StarterWare_OldReleases

Path of the example after installation: ~\ti\OMAPL138_StarterWare_1_10_04_01\examples\lcdkOMAPL138\edma

CCS project files for importing: ~\ti\OMAPL138_StarterWare_1_10_04_01\build\c674x\cgt_ccs\omapl138\lcdkOMAPL138\edma

0 wanseung yang over 9 years ago in reply to Shankari G

Intellectual 350 points

Hi Shankari

I've been checking the Startware

i'm trying to use QDMA

Regards,
Wanseung Yang

0 wanseung yang over 9 years ago in reply to wanseung yang

Intellectual 350 points

Hi Shankari

i found out QDMA is not for external event?

is it correct?

should i use EDMA for external event?

Regards,
Wanseung Yang

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Question about TMS320C6747 DMA Event