What are the benefits of using Direct Memory Access in the design?

[alam.tauqueer]

Hi,

What is DMA? and what are the benefite of using DMA in the design ?

Regards,
Tauqueer

 

[vinseth]

Direct memory access

Hope this helps

https://en.wikipedia.org/wiki/Direct_memory_access

 

[A.Anand Srinivasan]

Direct memory access

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....

 

[alam.tauqueer]

Direct memory access

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

 

[A.Anand Srinivasan]

Direct memory access

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....

 

[samuraign]

Direct memory access

could you give more references for better understanding.
Do we need to follow standard bus protocol.

 

[A.Anand Srinivasan]

Direct memory access

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....

 

[samuraign]

Direct memory access

I am designing my own DSP processor and would like to have my own non-AHB/APB based DMAC.

 

[jetset]

Re: Direct memory access

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

 

[e_ravikumarshinde]

Direct memory access

find the link having good explaination by INTEL
here