2008-03-06 09:26:30     PPP on CoreA and PPI on CoreB

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2008-03-06 09:26:30     PPP on CoreA and PPI on CoreB

Aparna Dutta (INDIA)

Message: 52157   




We are using the BF561 in a video server product. We are running uClinux on CoreA which connects to a GPRS modem by PPP over UART. We are running a VDK(VDSP)  project on CoreB which records video over the PPI interface.


We expect to capture video at the rate of atleast 25 frames/sec. This works fine when there is no PPP running  on CoreA.


But whenever CoreA connects to the network by running the pppd application, the PPI interrupts to CoreB are delayed. In that case, we are capturing only about 7-8 frames/second.


Does this indicate any conflicts regarding the interrupt-mapping on the 2 cores?


We can control the interrupt-mapping on the CoreB VDSP application, but how do we control the interrupt mapping on CoreA(uClinux) ?


Any other ideas about how we can debug this issue?




Thanks and regards,








2008-03-06 10:38:54     Re: PPP on CoreA and PPI on CoreB

Mike Frysinger (UNITED STATES)

Message: 52162    when you say "interrupt mapping" you mean interrupt priority ?  this is controlled in the kernel configuration menu




2008-03-12 15:50:19     Re: PPP on CoreA and PPI on CoreB


Message: 52404    Aparna:


As soon as you say " CoreB VDSP application" - most people here stop reading it. You are on your own.


There is not a good way to debug Linux and VDSP on the same device as Linux - the kernel may crash since VDSP/Core B overwrites something the kernel needed.


Good luck.