SDRAM Window0 Start Address

HvW

Hi,

I am working on a DM6446.

I am trying to get a picture I loaded in DDR2 (address 0x80200000) to be displayed in Window0. I have tried loading BMP and YUV422 format files ito DDR2, but the Window0 contents still does not display anything, only a green screen.

How do I specify the start address?

Is VIDWIN0ADR the start address where the picture is loaded?

Is this an offset value or is it the 0x80200000 value?

also, I do not understand how the 5 least significant bits need to be zero.

What other settings do I need?

Is there anything that I need to set up specifically for the VPBE to access the DDR2?

I am out of ideas, please assist.

Thanks,

Herman van Wyk

over 14 years ago

0 HvW over 14 years ago

Prodigy 140 points

Hi,

Another thing, is it possible to use the VPBE without using a DMA channel?

Thanks,

Herman

0 Nagabhushana over 14 years ago in reply to HvW

TI__Expert 4685 points

You can refer to arago code for register programming...

http://arago-project.org/git/projects/?p=linux-davinci.git;a=tree;f=drivers/media/video/davinci;h=e67b2f3bb5ae1f5d25f271902de1f42a9cd33847;hb=6ac7a3440bbd9fc30c175c205f0efd4b2fd8cde7

0 HvW over 14 years ago in reply to Nagabhushana

Prodigy 140 points

Hi,

Thanks for the response. I assume that I can load a image to the DDR2 and then have the VPBE get the picture from there without DMA.

How does this work though? How does the VPBE know what type of bus access needs to be done to transfer the picture?

Can you please explain this?

Thanks,

0 Nagabhushana over 14 years ago in reply to HvW

TI__Expert 4685 points

Well, you don't need to worry about DMA. Hardware takes care of this automatically.

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SDRAM Window0 Start Address