I have a doubt if DMA EVENTS of C5402 take any of the cpu time.
Like when Mbsp Receive Interrupt or Eternal Interrupt (INT 3) are
assigned as DMA Events, DO they interrupt the cpu . Can any one give
me some clues or where to find the info.
I tried spru302.pdf Enhanced peripherals reference of 54x
In section 184.108.40.206 there is mention of these events but no mention of
weather they exactly act like an interrupt or directly invoke DMA
without interrupting the Cpu.
Can some one help me on this please
C5402 DMA Events [Urgent]
Started by ●February 15, 2005
Reply by ●February 16, 20052005-02-16
>I have a doubt if DMA EVENTS of C5402 take any of the cpu time.
>Like when Mbsp Receive Interrupt or Eternal Interrupt (INT 3) are
>assigned as DMA Events, DO they interrupt the cpu . Can any one give
>me some clues or where to find the info.
There are two different things here:
1. DMA interrupt - it happens every time accordingly to your DMA interrupt settings (if DMA int is enabled, if interrupts are enabled globally, etc...) - after whole frame has been sent (received), ...
2. Transfer of each element by DMA (byte of memory). It works as fast as possible - if you didn't tell to DMA that there are an events to synchronize transfer of each element with. For example, when you have programmed that DMA event to synchronize with is McBSP send (receive) event, than DMA will move one element strictly after one element has been sent (received) by McBSP. Therefore, if McBSP doesn't work, DMA transfers doesn't happen and DMA interrupt doesn't happen - as DMA didn't transfer whole frame, for example.