Configuration DIO port USB-6212 OEM

[zgut]

I am using USB-6212 OEM daq card which has 32 DIO lines. Presently, I adapt to my system and  individual each port I configure by tasks. But I would like to know if it's possibility to configure an each port permanently, that is after connect my card to computer I will have same port as an output and other as input?

Regards

[Stefo]

Hi zgut,

I'm not sure what for would you need to have set Power Up Direction at the ports. You control it per task basis - anyway you need to have task to run measurement. If you need, you can create global task, but as far as I know, device will be anyway configured when you start the task. You can however set the power up state of lines as listed below. The default state after you power up your device is set to high impedance to protect your system.

From USB-621x User Manual

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At system startup and reset, the hardware sets all PFI and DIO lines to high-impedance inputs by default. The DAQ device does not drive the signal high or low. Each line has a weak pull-down resistor connected to it, as described in the specifications document for your device.

NI-DAQmx supports programmable power-up states for PFI and DIO lines. Software can program any value at power up to the P0, P1, or P2 lines. The PFI and DIO lines can be set as:
• A high-impedance input with a weak pull-down resistor (default)
• An output driving a 0
• An output driving a 1

Regards,

Martin Stefik

[zgut]

After connect card to computer all ports are tristate (default). I know that by using DAQmx I can change direction each port or lines. But I would like to have constantly 2 ports as output and one port as input, especially when I again connect my card to computer.

Regads

[Stefo]

hi zgut,

I think I know what you mean, but i would like to understand why you need it. Maybe there can be better way to solve you real challange.

When you say you would like to have them constantly input or constantly output, do you mean you would like to force direction in the way, that user will not be able to change it programmatically?

regards,

stefo

[zgut]

This DAQ card is connecting to my external device and one output port I am using as comunication port with device. Two input ports I am using as control ports. Configuration of these ports are not changing in the future. Presently, I am changing it programmatically after when I turn on my device and start software. But better will be if card have them constantly input or constantly output.

[Stefo]

It will not change any functionality. If you do not run the task, it will not communicate with the product. With tristate IO, your device will be able to drive the outputs safely, and in mean time you will not send incorrect data to it. So I believe tri-state is the best.

The only concern which i see you could have is, that some outputs from the board have to have certain values in order your external device to work properly. This you can controll with Power Up States of your DIO lines - and select certain level on lines where it is needed.

Regards,

Martin Stefik

[John_P1]

It sounds like you're talking about Programmable Power Up States.

These should be settable in MAX by right-clicking your board and selecting Properties.

Best Regards,