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Digital in signal is unstable PCI-6509 - i get garbage


Hello all,

i'm trying to do the most simple vi that you probably done before.
i want to read one port  (digital In PCI 6509).
I already build a new Task in  MAX and when i test the port i always get unstable signal.

i use the pci-6509 96DIO with CB-100 I/O with two CB-50 connector blocks and cables.
i configure port 2 to be digital input (pins numbers in the  CB-50  are : 15,13,11,9,7,5,3,1 )
i want to read the signal for each line in this port.
each line connected to relay (and the relay connected to 24VDC sensor)
so i have 8 relays connected to this port.
and when i read the port using the MAX i get garbage...

Please help

(P.S. sorry for double posting)

 thanks in advanced
Mor

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Hello Mor,

Before you create a task in MAX you may want to test the board using the test panels of the board.  Try testing it by first verifying that you can do digital output from one of the ports.  Then see if you can do Digital Input.  Make sure that the signals coming in are either TTL or CMOS compliant.  The voltages being passed to the digital input lines need to meet the specifications in the user manual.  After you have some successful tests with the board, you can move on to building the task or using an example program. 

Steven T

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