Digital I/O

cancel
Showing results for 
Search instead for 
Did you mean: 

Getting clock to run longer than CS signal in NI USB-8452 SPI

Solved!
Go to solution

Hi,

 

I am very new to SPI and not very versed with Labview but I when using the SPI VIs the clock pulses stop when the Chip Select goes from high to low.  The application that I am trying to interface is using the CS in an inverted manner from normal, it is low undernormal conditions but goes hi to communicate.  With the board that I am using, the data is transmitted after the CS goes back to the low state but I need the clock pulses to keep going to get the data.  Is there a way to keep the clock pulses going past the CS transition?

0 Kudos
Message 1 of 4
(3,304 Views)
Solution
Accepted by topic author todd1313

If your target device uses the CS line in an inverted manner, and accomodating that in software is giving you unexpected results, could you add a physical inverter on the line to the target? That way, the target can use its inverted CS logic, but the rest of the system could operate as normal.

Kathryn K.
Technical Support Engineer
National Instruments
http://ni.com/support
0 Kudos
Message 2 of 4
(3,277 Views)

You can use the scripting API to do an inverted CS signal, since you control it manually.

0 Kudos
Message 3 of 4
(3,225 Views)

The physical inverter may be the way to go.  The CS line defaults to high while I need low.

0 Kudos
Message 4 of 4
(3,221 Views)