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Hi Mayank, first of all, which target processor do you use? I'm using a C6416, maybe the configuration for C62x and C67x processors is different from mine, but I hope this will help you though: There are two different types of starting an EDMA transfer, event triggered and CPU-initiated. Each EDMA channel is associated with a special event, for example Channel 4 with EXTINT4. You have to configure this channel, enable it (EDMA_enableChannel(name) or by DSP/BIOS), and enable the external interrupt 4 via IRQ_enable(IRQ_EVT_EXTINT4), because it is associated with this channel. Now the channel is ready and waiting for the EXTINT4-event, the IRQ_enable does not generate any interrupt! Only if you connect a signal to the EXTINT4-Pin of your board or DSP, and that signal goes HI or LOW with a specific timing, an interrupt is generated and the EDMA transfer is triggered! I use this method to synchronize an EDMA transfer with an external clock. The other method is more suitable for your problem, I think. The events for the channels can also be triggerd, by manually writing in the event set register (ESR). By that way, you can trigger your channel at any time you want (for example at the same time you change a variable), and it can also be triggered with a special command in your code and not by an external source as described above. I'm sorry, but I have not tried this method so far, I only know that it is a possibility to trigger your events manually, should be described in "TMS320C6000 EDMA Controller Reference Guide" from the TI Homepage. Hope I could help you... Andreas ----- Original Message ----- From: "mayank agarwal" <> To: <> Sent: Thursday, December 16, 2004 9:12 AM Subject: EDMA Problem revisited > Dear Andreas, > i am facing some problems in EDMA configuration. > 1.I want to trigger EDMA transfer from one memory > location to another upon change in value of > size,if i have to generate interrupt to accomplish > this,or suppose if i am enabling channel 4 for EDMA > transfer then giving the > instruction IRQ_enable(name) will generate interrupt > on external pin4 and that will trigger > EDMA transfer or there is some other procedure to > trigger EDMA transfer. > 2.Another doubt is the value of element count is > varying so if we want to configure the value of > element count graphically how to accomplish this. > Please guide me regarding the above doubts. > Regards, > Mayank Agarwal > > __________________________________ |
Re: EDMA Problem revisited
Started by ●December 16, 2004
