Example_2833xDMA_XINTF_to_Ram.c

Alex Oren

Intellectual 480 points

Hi,

I'm trying to modify this example to perform a DMA copy from RAM to XINTF - just change the direction.

Is it possible?

I changed the source and destination for the DMA but this is probably not enough

DMADest = &DMABuf2[0];
DMASource = &DMABuf1[0];

What else should I change?

Thanks

over 7 years ago

0 Whitney Dewey over 7 years ago

TI__Guru 50595 points

Alex,

I suppose if you're moving data from Buf1 to Buf2 you may also want to change the buffer initialization loop to fill Buf1 with data and Buf2 with zeroes. As far as I can tell from looking at the code, that should be the only thing.

Do you ask because it is not working? If so, can you give me more details about the failure?

Thanks,
Whitney

0 Alex Oren over 7 years ago in reply to Whitney Dewey

Intellectual 480 points

Hi Whitney,

The original code moves data from XINTF to RAM (from Buf2 to Buf1). I would like to move data from RAM to XINTF (from Buf1 to Buf2).

So I started with just changing the DMA destination and DMA source.
Regarding the initialization - I can't see how this helps - this is just the initial values in the BUFs.

Yes, I tried - there is no failure - just teh values in XINF remains without change.
I am using MEMORY window comparing 0xC000 with 0x20fC00

Actually the row: DMABuf2[i] = 0; do nothing in the XINTF memory and it stays unchanged FFFF.
So I believe there is something else that should be done to enable access to XINF zones.

Thanks,
Alex

0 Whitney Dewey over 7 years ago in reply to Alex Oren

TI__Guru 50595 points

It's strange that not even DMABuf2[i] = 0 was working. Did the line in the original example DMABuf2[i] = i write to XINTF memory?

Whitney

0 Alex Oren over 7 years ago in reply to Whitney Dewey

Intellectual 480 points

Hi Whitney,

In the original example DMABuf2[i]=i is not working as well. The values are FFFF and it is copied to the RAM L4 DMABuf1.

So it is something else - maybe any enable for XINTF writing?

0 Alex Oren over 7 years ago in reply to Alex Oren

Intellectual 480 points

Maybe someone can help with this issue?

Thanks,

Alex

0 Vivek Singh over 7 years ago in reply to Alex Oren

TI__Guru** 109165 points

Alex,

Is the setup you are using us new or it has been tested for XINTF access before? If this is new setup then you need to make sure all the XINTF signals are connected properly. Since even a simple CPU write is not working, I am suspecting some signal hook-up issue.

Regards,

Vivek Singh

0 Alex Oren over 7 years ago in reply to Vivek Singh

Intellectual 480 points

Hi Vivek,

I am using TMS320C2000 experimenter kit with F28335.
XINTF is an external memory, so should I connect something external to implement this? I think I am missing something very basic...
I read the spru949d and SPRS439M documents but it is mostly about different software configurations.

BTW, I do able to perform a write from Lx SARAM to Ly SARAM

Thank you,
Alex

0 Vivek Singh over 7 years ago in reply to Alex Oren

TI__Guru** 109165 points

Yes, you need to connect an EXTERNAL RAM device to XINTF interface.

0 Vivek Singh over 7 years ago in reply to Vivek Singh

TI__Guru** 109165 points

Alex, do you any further query on this topic?

0 Alex Oren over 7 years ago in reply to Vivek Singh

Intellectual 480 points

Is something available from TI?
Vivek, maybe you can please also help me with this topic: e2e.ti.com/.../1937071
Thank you

0 Alex Oren over 7 years ago in reply to Alex Oren

Intellectual 480 points

Hi Vivek,

There is something else that I'm trying to understand.
When using the example Example_2833xDMA_XINTF_to_Ram.c as is, without any change, the DMABuf2 is allocated to a specific adders:
0020fc00 83f0 (0020fc00) _DMABuf2
At this address I can see the FFFF values. After the initialization table DMABuf2[i] = i; nothing changes.
And at the end of the code the FFFF is copied to DMABuf1 at RAML4.
So if XINF is an external RAM device that I need to connect, where these FFFF are cumming from and why I can see the 0020fc00 address on my memory browser?
I'm using the MS320C2000 experimenter kit with F28335.

Thanks in advance,
Alex

0 Vivek Singh over 7 years ago in reply to Alex Oren

TI__Guru** 109165 points

Alex,

That's because the GPIO pins associated with EMIF data lines will have some value (if pulls enable then it'll be '1') and XINTF will read these pin value and display in memory browser. If you drive '0' on any of these data pins then you'll see the different value.

You need to connect external device on XINTF interface to have it working properly.

Regards,

Vivek Singh

0 Vivek Singh over 7 years ago in reply to Vivek Singh

TI__Guru** 109165 points

Let us know if you have further queries on this.

0 Alex Oren over 7 years ago in reply to Vivek Singh

Intellectual 480 points

No, thanks, understood

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Example_2833xDMA_XINTF_to_Ram.c