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Hi all, I'm using DSKC6713 and I want the DSP to search for a certain sequence of samples in a buffer, received from the McBSP. As soon as this sequence is found, I want the element count of that channel to start from zero (i.e, some kind of reset to the EDMA channel). Is that possible, and if so, what register should I write to to make this happen? My EDMA transfer is element sync'd, and my events are McBSP receive. Thanks, Offir. |
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EDMA reset
Started by ●September 7, 2004
Reply by ●September 7, 20042004-09-07
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Offir- > I'm using DSKC6713 and I want the DSP to search for a certain > sequence of samples in a buffer, received from the McBSP. As soon as > this sequence is found, I want the element count of that channel to > start from zero (i.e, some kind of reset to the EDMA channel). Is > that possible, and if so, what register should I write to to make > this happen? That does not sound like a good idea. You will be messing at the chip level with DMA transfers in "mid-stream"; if the data rate is high, you could miss/overwrite samples or otherwise cause some glitch. Why not just note the sample offset at the time the sync sequence is located? For each buffer after that point, you take some of the current buffer and some of the previous, and based on the offset, and process as needed. -Jeff |
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Reply by ●September 7, 20042004-09-07
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Offir- On Tue, 07 Sep 2004 14:12:21 -0500, Jeff Brower <> wrote: > > Offir- > > > I'm using DSKC6713 and I want the DSP to search for a certain > > sequence of samples in a buffer, received from the McBSP. As soon as > > this sequence is found, I want the element count of that channel to > > start from zero (i.e, some kind of reset to the EDMA channel). Is > > that possible, and if so, what register should I write to to make > > this happen? > > That does not sound like a good idea. You will be messing at the chip level with DMA > transfers in "mid-stream"; if the data rate is high, you could miss/overwrite samples > or otherwise cause some glitch. Even I think that its not a good idea to meddle with the transfer when its actually taking place. But if your data rate is not that high and you have *enough time* between subsequent samples then how about setting EDMA transfer for just one sample and let it interrupt CPU after every sample and let CPU deal with finding that sequence you are looking for. I still think the method I have suggested doesnt make much sense since the onus of processing and transferring data is back on CPU and kills the meaning of EDMA . ( It mite be of some help in scenarios where ur data is coming at vrey slow rate and hence CPU can utilize the time in between samples to do other things) Just a thoght Tarang > > Why not just note the sample offset at the time the sync sequence is located? For > each buffer after that point, you take some of the current buffer and some of the > previous, and based on the offset, and process as needed. > > -Jeff > > _____________________________________ > Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. > > _____________________________________ > About this discussion group: > > To Join: Send an email to > > To Post: Send an email to > > To Leave: Send an email to > > Archives: http://www.yahoogroups.com/group/c6x > > Other Groups: http://www.dsprelated.com > > Yahoo! Groups Links |
