When Using PFI 9 as Data valid signal what are the setup/hold times & frequency

[doug12]

Hi,

we are trying to use PFI 9 as a data valid signal but have had some problems when running. I've found that to fix it I've had to slow everything down. Could someone tell me what the setup & hold times of data are when using the PFI signal in this way?

What edges are used?

& what is the minimum time I need to hold the signal low for?

Many thanks

Doug

[doug12]

Sorry forgot to say we are using the 6259 PCI card

[JamesC]

Hi Doug,

I am not entirely sure what you are trying to do. Are you inputting a signal to tell the DAQ card to acquire data, or are you outputting a signal to tell a 3rd party device to accept the data being generated from the daq card.

The PFI lines follow the TTL spec, so should work with a pulse of no less than 10nS, and a rise and fall time of no more than 50nS, to be able to detect the edge.

Regards
JamesC
NIUK and Ireland

[doug12]

Hi James,

we are trying to use PFI as an input to say the data is valid. I have now found the info I require in the M-Series user manual on p B-31 (Data Input sample timing diagrams)

Many thanks

Doug