Problem with DMA ISR and GPT ISR on C5505 usb stick

Ramesh G

Hello all,

I am facing some problems while programming with DMA and GPT on the C5505 USB stick.

I am using the DMA to copy samples to and from AIC3204 over I2S. DMA ISR is used to manage the ping-pong buffering. The program just tries to read samples from input and then paly them back on the line out. This is working fine as a standalone program.

I am also trying to run a GPT (Timer0) with the above module which will give me periodic interrupts (I need a counter for time sync with some other hardware). The ISR for this GPT just increments a reference counter. I have observed a problem when I try to run the GPT code with the above DMA code.

The program runs well for a very short time (close to 1 sec), but after that one of the two ( DMA or GPT) stop responding. If the DMA is still running, the reference counter (GPT ISR) stops incrementing and if the GPT counter is going right, the DMA stops working. I figure this is some problem with conflict in the ISR of DMA and GPT. I have tried debugging by checking the values of the interrupt registers(IER0), and the interrupts are still enabled.

What is causing the interrupts to stop responding? Am I missing something in the configuration?

Any pointers would be very helpful.

Thanks,

Ramesh

over 14 years ago

0 Peter Chung over 14 years ago

TI__Expert 8065 points

Ramesh,

Do you think you can send us your project that you ran on the eZdsp?

Regards,

Peter Chung

0 Ramesh G over 14 years ago in reply to Peter Chung

Prodigy 105 points

Hello Peter,

Let me know where I should send the project files.

Thanks,

Ramesh

0 Peter Chung over 14 years ago in reply to Ramesh G

TI__Expert 8065 points

Ramesh,

Sorry for the late response. I was on business trip.

I think you can attache your project file here. Try "option".

Regards,

Peter Chung

0 Ramesh G over 14 years ago in reply to Peter Chung

Prodigy 105 points

7382.AudioGPT.zip

Hello Peter,

Thanks for your response. I have attached the project files here.

Regards,

Ramesh

0 Peter Chung over 14 years ago in reply to Ramesh G

TI__Expert 8065 points

Ramesh,

Thank you. I will check if one of my team members can take a look at your code.

Regards,

Peter Chung

0 Peter Chung over 14 years ago in reply to Peter Chung

TI__Expert 8065 points

Ramesh,

I can't build the project. I think there are some file pathes that I don't have. Anyway, let me try a simple thing first.

You are using the timer0 only, right?

Let's replace the line "(*iafrReg) = (*iafrReg)| (0x0001) ;" in "interrupt void ticker_ISR(void)" by

"IAFR_REG = 0x0001; // clear timer0 interrupt flag"

Then you need to add the following line into your code.

#define IAFR_REGS *(ioport volatile unsigned *)CSL_IAFR_REGS

I am not sure if it will resolve the issue, but I want to make sure that you clear the timer0 flag at every time correctly.

0 Ramesh G over 14 years ago in reply to Peter Chung

Prodigy 105 points

Peter,

Thanks for your response.

You are right, I am using Timer0 only.

I made the changes as suggested but it has not resolved the issue.

Regards,

Ramesh

0 Peter Chung over 14 years ago in reply to Ramesh G

TI__Expert 8065 points

Ramesh,

Is there a way for you to send me buildable project? I am sorry, but I am doing multi-tasking, I would like to have a project that I can build here and run quickly.

Regards,

Peter Chung

0 Ramesh G over 14 years ago in reply to Peter Chung

Prodigy 105 points

Peter,

I think the project is not building due to some path issues.

Can you suggest me some way to send buildable project so that these path issues do not arise?

Thanks for your help.

Regards,

Ramesh

0 Peter Chung over 14 years ago in reply to Ramesh G

TI__Expert 8065 points

Ramesh,

Another way I can help is that I can insert a Timer0 interrupt to the audio filtering demo code. If I can get both interrupts (DMA and Timer) properly, then I will send it to you. Please give me the following info.

- CPU frequency

- Timer0 interrupt frequency (clock divider and counter)

I hope you are OK with this.

Regards,

Peter Chung

0 Ramesh G over 14 years ago in reply to Peter Chung

Prodigy 105 points

Peter,

That would also be fine. Here is what I am trying to get working.

CPU frequency - 100MHz

Clock pre-scale Divider - GPT_PRE_SC_DIV_0 (i.e.0)

prdLow = (getSysClk()/2)/32.768

prdHigh=0x0000

I am trying to get an interrupt every 30.5us. I have checked by changing the counter values for interrupts to occur less frequently, but the problem still persists.

Thanks for your help.

Regards,

Ramesh

0 Peter Chung over 14 years ago in reply to Ramesh G

TI__Expert 8065 points

Ramesh,

I am sorry that I have not had a chance to look at this. I have been and am swamped. Let me check if other team members can look at this.

Regards,

Peter Chung

0 Timothy Sapio over 13 years ago in reply to Peter Chung

Intellectual 310 points

Well, whaddaya know, I'm having EXACTLY the same problem. PLEASE get back to him! I can provide my project if it helps.

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Problem with DMA ISR and GPT ISR on C5505 usb stick