ARM+DSP timer sharing

serdar

Other Parts Discussed in Thread: OMAP-L138

Hi,

We are designing a measurement tool with L138 and I have question marks. We will use Linux and DSP/Bios. DSP will read ADC then some tasks process the data that comes from ADC. I need two timers. First one is for measurement frame such as, 1sec, 10sec and second timer for triggering ADC conversion.

Clock source must be RTC oscillator for first timer. I have accurate crystal and timing frame must be accurate. Can I set the RTC clock as timer source for a timer in DSP side during Linux uses RTC? I am not sure how ARM and DSP share the RTC clock circuit and timers.

I need to set second timer as DMA trigger source and DMA must read ADC over SPI. I think there is separate DMA Controller in DSP side and I can configure the timers for ARM and DSP. I didn't check the peripheral configuration in Linux.

Do you see any problem in this scenario? What subjects should I concern?

Thanks in advance

Serdar

over 14 years ago

0 Erik Welsh over 14 years ago

TI__Prodigy 490 points

Serdar,

For more information on the timers, please refer to the Timer User Guide: http://focus.ti.com/lit/ug/sprufm5d/sprufm5d.pdf

For more information on the RTC, please refer to the RTC User Guide: http://focus.ti.com/lit/ug/sprufm3c/sprufm3c.pdf

To get a better understanding of the clock sources available for the Timers, please refer to: http://focus.ti.com/lit/ug/sprugm7e/sprugm7e.pdf Section 7.3.7

To better understand the interupts to the processor, you can use: http://focus.ti.com/lit/ug/sprugm7e/sprugm7e.pdf Section 3.2.2.1 for DSP interrupts; Section 12.2 for ARM interrupts

To better understand the DMA events: http://focus.ti.com/lit/ds/symlink/omap-l138.pdf Section 5.9

Overall, I don't see any issues with using the OMAP-L138 for this application.

Regards,

Erik

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ARM+DSP timer sharing