How to write directly to a mapped DAC?

[Dr_Laine]

I am running LV7.1RT with Motion 6.1.2 on a PXI-8145 with 7350 motion controller. I would like to write directly to the DAC mapped to Axis 1 for System Identification purposes (I want to send open-loop commands directly to the plant). However, the Load DAC.vi should not be used on a mapped axis. Any ideas how to ID my plant (I would like to separate the 7350 control loop away from the plant)? Thanks.

[ColinAE]

Hello.

I have one idea that I would like to throw out there, just as a suggestion. You could actually momentarily switch the Axis to an open-loop stepper Axis, where you could then load a DAC value. Once you are done with the 'ID' phase, you could then re-assign as a servo Axis and go from there. . .

Its just a thought. Without fundamentally changing the axis type/mapping, you should not be loading the DAC value, as you mentioned.

Just a thought!
Regards,
Colin C.
Applications Engineering

[Dr_Laine]

Thanks, I will try this.

L