[mythtv-users] Problems with multiple pvr cards

[Yan-Fa Li]

On 5/8/07, Brian L. Walter <blwalter at gmail.com> wrote:
> Greetings,
>

Hey,

> I've got 1 pvr-500 and one pvr-150, running ivtv 0.10.1 with myth
> 0.20-fixes as of 5/6.
>
> I have run a couple 30 minute cat /dev/videoN against all 3 devices
> simultaneously, with no problem.
>
> However, when Myth goes to record on all 3, I start getting ENC DMA
> Errors, anywhere from  immediately to 20-30 minutes.
>

Usually this is motherboard related.  I have a triple tuner set up
with a PVR150, PVR250 and HD5500 and it runs without skipping a beat.
What chipset is at the core of your motherboard?  VIA chipsets are
particularly problematic.

What distribution and kernel are you running?

> I've read that there is an interrupt issue with the 0.10.1, and was
> wondering if this is a result of that issue.
>
> This problem does not occur when only 2 of the three inputs are in use,
> only with all three.  The only way to clear it up is to reboot, because
> this situation will eventually lead to dma timeouts, and driver not
> responding....then...system crash.
>
> I just want to make sure I'm not chasing my tail when this is all
> related to the interrupt issue, if there *is* currently an issue...
>

If you can make sure the cards aren't sharing IRQs that's helpful.
Known good motherboard chipsets are Intel, Nvidia and SIS.

Good luck with debugging this.

Yan