Hi,
So you are using a standard RC servo. You might actually be able to control this directly with the 6211. These kinds of servo motors take a PWM signal to determine the position of the servo-horn. If you do a search on google you can probably find a lot of information about how the PWM signal should be, but take a look at
this link which tells you how you should modulate the signal. You can then use the counter on your DAQ device to generate this signal. Take a look at
this link for an example showing you how to accomplish this. As far as power from the servo, you should probably use an external power supply as your DAQ device might not have enough current to drive the servo. I am not sure how much current does the servo require, but the DAQ card can only give you 50mA MAX on the 5V+ lines.
Eli S.
National Instruments
Applications Engineer