USB6501_OEM DIO Push-pull configuration

[marcounet]

Dear Support,

I'm using an OEM 6501 USB Device from NI, at power up prior to any LabVIEW commands, digital output level is HIGH ( open drain with internal 4K7 pull-up resistor). Unfortunatly, my application needs a LOW level at default, so i have to replace Open Drain configuration by push-pull and i would like that OEM USB 6501 device starts automatically with a low level.

How to proceed to configure Push-pull mode to replace Open Drain default mode with LabVIEW commands?

Do i need to suppress all 4K7 pull up resistors on the board?

Thanks for your help.

Regards,

Marc,

[GerdW]

Hi marcounet,

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@marcounet wrote:

How to proceed to configure Push-pull mode to replace Open Drain default mode with LabVIEW commands?

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There's no way to change the power-on state, your device acts exactly as described in the specs: "input (high-impedance)" on startup!

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@marcounet wrote:

Unfortunatly, my application needs a LOW level at default,

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Options:

• Use other hardware, capable of setting the default power-on state.
• Add your own (external) hardware to ensure the required power-on state. Use a DO pin of the 6501 to switch the outputs of your external hardware as required…

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@marcounet wrote:

Dear Support,

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This is a public forum, mainly driven by volunteers.

When you want to contact the NI support you need to start a service request within your user account…

[PhillipDBrooks]

The 6501 I/O pins do not provide power-up default settings.

See Re: Can I change the power on state of the USB-6501? - NI Community

There are other models (USB-6509) that support power-up defaults.

[marcounet]

Thanks i don't know if USB6509 exist in OEM version.

Regards,

Marc,