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We appreciate your patience as we improve our online experience.
01-19-2022 01:23 PM
CVI 2019, Win10.
Can somebody send me some example code for a DIO card/module, in particular how to set bits or nibbles for different directions. C language, DAQmx function calls please. The only vaguely related information I have seen so far is old, like 2008, and I don't trust it. (Talks about reserving a task) I have not seen anywhere how to select bits or nibbles.
Is it true that for a DIO module such as the 32-ch 9403 one has to create both an input task and an output task, that one task to do reads and writes does not work?
I understand the function calls to create a task, set up the 32-bit path as a single channel for reads, and separately for writes, start the task, and how to read and write 32-bit UINTs to the device.
01-19-2022 02:52 PM
Not a CVI guy, but used DAQmx a lot.
A digital line can be an output or an input but cannot be both. Channels/lines configured as output must go into a Digital Output task and similarly inputs to Digital Input task (yes, they are separate).
Next, no, you cannot write to an input task or read from an output task because the functionality is fixed during DAQmx task creation.
High Speed 655x and Digital Pattern 657x instruments have on the fly direction change ability at the cost of adding a digital output and input resource in the hardware design for every line.
01-23-2022 12:44 PM
Hi,
Open CVI,
Go to Help menu.
Go to find examples.
There are various examples for analog and digital channels.
Alternatively on the bottom left side you can enter your hardware details and then do a specific search wrt your hardware controls.
Hope this helps.
Ravi
02-08-2022 02:01 PM
Hi Ravi,
is there any examples for state change ?
Thanks,
Pavan
02-22-2022 04:46 AM
Hi,
I think you meant state change of D I/O.
Do a search of digital read or digital write :
Hope this helps.
Ravi