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alam.tauqueer
Joined: 19 Jun 2007
Posts: 128
Helped: 3
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 19 Mar 2008 18:35 Direct memory access |
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Hi,
What is DMA? and what are the benefite of using DMA in the design ?
Regards,
Tauqueer
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vinseth
Joined: 06 Jul 2007
Posts: 37
Helped: 3
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| 20 Mar 2008 14:40 Direct memory access |
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Hope this helps
http://en.wikipedia.org/wiki/Direct_memory_access
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A.Anand Srinivasan
Joined: 15 Oct 2005
Posts: 1764
Helped: 213
Location: India
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| 22 Mar 2008 18:07 Direct memory access |
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| dma is direct memory access in which two peripherals communicate between them(using bus) without the usage of the processor.... during this time the processor does background processes without use of the bus....
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alam.tauqueer
Joined: 19 Jun 2007
Posts: 128
Helped: 3
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| 26 Mar 2008 5:53 Direct memory access |
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What is the benefit of using DMA?
Or is there any specific need where we should use DMA with processor?
Kindly answer my above question I will be thankful to you.
Regards,
Tauqueer
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A.Anand Srinivasan
Joined: 15 Oct 2005
Posts: 1764
Helped: 213
Location: India
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| 26 Mar 2008 8:56 Direct memory access |
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| using DMA increases the speed of transfer and also since the processor is not involved during that time it can do other processing work that doesnt involve the bus so the processing speed is also increased....
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samuraign
Joined: 18 May 2006
Posts: 115
Helped: 6
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| 01 Aug 2008 15:15 Direct memory access |
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could you give more references for better understanding.
Do we need to follow standard bus protocol.
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A.Anand Srinivasan
Joined: 15 Oct 2005
Posts: 1764
Helped: 213
Location: India
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| 07 Aug 2008 19:49 Direct memory access |
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| yeah every such process would have its own protocol.... in reference which device due you need info on DMA.... i mean the product number of type of microprocessor or controller....
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samuraign
Joined: 18 May 2006
Posts: 115
Helped: 6
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| 18 Aug 2008 3:40 Direct memory access |
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| I am designing my own DSP processor and would like to have my own non-AHB/APB based DMAC.
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jetset
Joined: 17 Jun 2004
Posts: 145
Helped: 10
Location: Panama
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| 19 Aug 2008 16:47 Re: Direct memory access |
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For example if you have a VGA card with DMA controller, you can reserve a space on system RAM to store images and the VGA can read it directly from the RAM memory without asking the processor, because the VGA controller is like a separate processor.
Obviously there are arbitration and synchronization issues involved since they can not access the memory at the same time or even at the same speed.
So we can say that advantages of using DMA is that you can have separate entities processing data withiut asking the main processor, and you can interface entities that run at different rates.
Regards
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e_ravikumarshinde
Joined: 08 Feb 2008
Posts: 30
Helped: 3
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| 20 Aug 2008 6:06 Direct memory access |
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find the link having good explaination by INTEL
here
http://www.edaboard.com/viewtopic.php?p=1070507#1070507
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