DO on myRIO connector C

[TomSAVU]

Hi,

I want to enable a motor drive using a digital output on connector C of myRIO 1900.

It's not working.

The drive is a BTS7960, it seems that its control input level is between 3.3 and 5V, so the voltage level seems not to be the problem.

Is this because the DOs on connector C are pulled-down?

[RIObotics]

Hi there,

To debug, you can use one of the 5V pins on the myrio as the enable input of your driver.  That way you know it will always be 5V, and takes the guesswork out of your DO. 

If the motor still doesn't turn, it could be a problem with your PWM signal coming from your myRIO.  In this case, you can probably use an arduino board to test your motor driver, the manual PDF has a section for this.

BR

John

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[TomSAVU]

Hi John,

Thanks a lot for your answer.
I've already checked with 5V and it's working.

Does this mean that digital lines (or at least one of them) on connector C are burnt?

Or, because they are pulled-down, I have to add some resistor?

[TomSAVU]

Connecting DIO 5 to DIO 1 works just fine.
Maybe the BTS7960 drive needs 5 V, even if in its datasheet is written "Control Input Level: 3.3~5V".

Maybe the 3.3 V are only for the PWM and 5 V are needed for enabling.

[RIObotics · Accepted solution]

Hi Tom,

That's right, the DIO lines on the myRIO are rated at 3.3V.  It looks like your enable input needs 5V to work.  Glad you solved the problem!

BR

John

Add motion to LabVIEW in 30min or less - TENET EMotion
Finding it hard to source legacy NI hardware? Try Extend Test