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Limit of NI PCI cards in a system?

Hello,

What is the maximum number of PCI cards a system can have? Most motherboards
have 5 PCI slots, but I have seen extension boxes that can add up to 20 PCI
slots. I want to use a PCI 6071, PCI 6602, a PCI DIO 96. And add from 1 to 8
more PCI 6024E boards. The reason for this is I need to add a group of
functions that require fast DAQ (30,000 S/s) two counters with a .1 ms
resolution, 2 analog outputs plus 8 digital I/O.
Also, What is the maximum number ofboards I can synchronize with a RTSI
cable? I want all of my counters to start simultaneously.

Thanks

L. Villa
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This really depends on your system/motherboard. You may want to contact the manufacturer to see what they same. An alternative is of course going to a PXI based solution with a MXI card interface. This would allow you to cable from you computer to the PXI via MXI and add Compact PCI cards to the chassis, which would appear as PCI cards in the system. You could also go with a PXI controller in the PXI chassis and completely avoid the desktop PC. The advantage of course of PXI is the number of slots available. 1 chassis can support up to 18 cards and then chassis can be daisy chained together.

Check out: http://sine.ni.com/apps/we/nioc.vp?cid=1525〈=US

Hope this help!!
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Thanks.
My motherboard can have an extension of up to 20 PCI cards the question is
is there a conflict with memory addresses, DMAS etc using 12 PCI cards?
What about RTSI cables? can I send a common start signal to all 12 PCI
cards.

Thanks

LVilla

"Super Fly" wrote in message
news:5065000000050000002A4D0000-1004225886000@exchange.ni.com...
> This really depends on your system/motherboard. You may want to
> contact the manufacturer to see what they same. An alternative is of
> course going to a PXI based solution with a MXI card interface. This
> would allow you to cable from you computer to the PXI via MXI and add
> Compact PCI cards to the chassis, which would appear as PCI cards in
> the system. You could also go with a PXI controller in
the PXI
> chassis and completely avoid the desktop PC. The advantage of course
> of PXI is the number of slots available. 1 chassis can support up to
> 18 cards and then chassis can be daisy chained together.
>
> Check out: http://sine.ni.com/apps/we/nioc.vp?cid=1525〈=US
>
> Hope this help!!
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LVilla wrote:
>
> Thanks.
> My motherboard can have an extension of up to 20 PCI cards the question is
> is there a conflict with memory addresses, DMAS etc using 12 PCI cards?
> What about RTSI cables? can I send a common start signal to all 12 PCI
> cards.

In general, the PCI standard was only designed to support a limited
number of boards.
If there are too many, you may get issues caused by too much capacitance
and poor propagation of important electrical signals.

(Not just a problem with NI PCI boards.)

Yes, you may be able to plug in 20 PCI boards, but don't expect that
they will all work to spec.
If you are unlucky, problems may even hang the PC.

Also, your chassis may not have enough power to support them all. Even
if it d
oes, it may not have enough cooling, with not enough airflow in
the right places. Industrial computers are better in that respect, but
the main PCI issue will still remain.

As Filipe said in another reply, it's best to consider other options ...

Best, Mark
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L Villa;

Historically speaking,the RTSI bus was never intended to support more than eight cabled
devices. Regarding your other question, there isn't a specified maximum number of PCI DAQ boards you can use, but, keep in mind that, as the PCI bus has only three DMA channels which are shared in between devices, if you start to increase the number of devices to much, the performance of those devices will drop consistenly, as far as data transfer from the on board memory to the computer memory.
To solve that problem, you have the option of using the SCXI modules which are external multiplexers that you can connect to one single DAQ board and have the channel count increased to a couple of hundreds, if you need to.
I'd advise you to take a look at the SCXI modules b
efore you start increasing the number of PCI DAQ boards on your computer.
Hope this helps.
Filipe
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