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Re(2): Re(2): External DMA interrupts
>Do you get the data out on the external DMA channel as expected ?
>One reason could be if you enable the external DMA interrupt (in the
>interrupt mask) before you start the external DMA channel. Possibly there
>is also a small latency after giving the start command to the external
>channel until it is actually started.
Yes, i had the external DMA interrupt enabled *before* I started the
external DMA. I thought that the interrupt will be triggered when the run
bit will be cleared, not when the run bit *is* clear. After this change in
the code I receive only one interrupt, the expected one.
One final question : If I enable the interrupt after starting the channel,
what happend when DREQ ist still high ? Is it possible to loose an
interrupt because the transfer has been started/finished (e.g. burst mode,
only one burst) before I enable the interrupt ?
>I hope this helps
Yes, thanks a lot !
Dipl. Inform. Arne Bockholdt
REA Elektronik GmbH
Tel. +49 (0) 6154 / 638-115, Fax -195