Inhibit output not responding in PCI7344 motion controller.

[Pras]

I need to use inhibit output as a enable signal for a third party drive unit. I have configured it as active high and enabled it. Inhibit output is pulled up to 5V with 270 ohm resistor. But inhibit output is not changing its state irrespective of it is being enabled or disabled? Please suggest any corrective action? Thank you.

[Brent_R]

Hello Pras,

Are you using the UMI to connect to your drive or cabling directly to the 7344?

If you are connecting directly to the 7344, then the inhibit output should sink plenty of current to pull the output low with a 270 ohm pull up resistor. Make sure the inhibit is enabled and the polarity is set appropriately for your application. Initialize the controller and check the output state. Go to the 1D Interactive section and press the "Kill" button to disable the drive. You should see the inhibit line change state.

If you are using the UMI, then there are more settings to consider. Make sure to set the inhibit output polarity switch on the UMI appropriately. Enable the inhibit output in software, set the polarity, and intialize the controller. The in
hibit output on the UMI should be inactive. If it is active (ie. in an inhibited state), then try changing the inhibit input polarity switch on the UMI. The UMI will "OR" together the per axis inhibit from the 7344, the per axis inhibit input on the UMI, and the inhibit all input on the UMI. Once the polarities are set correctly, you should be able to see the output changing state.

Regards,

Brent R.
Applications Engineer
National Instruments

[algames]

You might want ton check the following document for help:

http://digital.ni.com/public.nsf/websearch/4654434B4A35B90A86256D9700646E02?OpenDocument