Re : pxi backplane 10MHz

[Nico2808]

Hi,

  I'm using a PXI-1042Q with a NI-6541 Digital I/O and a NI-5122 high speed digitizer. I'm using the 10MHz backplane clock to synchronize these cards, and I would like to know how can I change this clock. Regarding to the manual, it's possible if I drive another clock on pin PXI_CLK10_IN (slot 2 star trigger). But can I do the same if I put the NI-6541 or NI-5122 on slot 2 and drive a external clock by the CLK_IN connector ? 

Thanks

[MobyJ]

Hi Nico,

you absolutely cannot use another clock than the 10MHz on the 10MHz line of backplane.
Therefore, you can use another lines like "start trigger" or "PXI Star (depending of you board specification).
you must specifies in your application the clock source you used, for you 5441 and 5122 board and specifies too which clock to share on backplane with .

Best regards.

 Moby

[Nico2808]

Hi Moby,

Thank you answering and make sure I don't want to remove the 10MHz bakcplane line. But can I use the backplane line with another clock to synchronize all of my PXI module ? in the manual they say : "You can drive PXI_CLK10 from an external source through the PXI_CLK10_IN pin on the P2 connector of the Star Trigger Slot. Refer to Table B-4, P2 (J2) Connector Pinout for the Star Trigger Slot. Sourcing an external clock on this pin automatically replaces the backplane’s 10 MHz source." That's why I'm asking if it's possible to put a 5MHz (for eample) clock on 6541 clk_in pin and drives it to be the backplane clock for all my modules ?

Thank you !!

[MobyJ]

Hi,
absolutly not!
this is working only with 10MHz source.

PXI_CLK10_IN is only used for synchronise both PXI chassis.

I council you to get information about PXI_STAR line. It must be your solution.

VBR,
MobyJ

Message Edité par MobyJ le 07-23-2007 09:27 AM