Hello,
Please refer to the specification and manual for this device linked below. In the specification on page 6, it shows the Digital input and output characteristics. The min and max range for the logic accounts for both 3.3 and 5 volt logic levels for a Digital input. The 6212 is actually not a listed device on the digital output characteristics table. Please let me know if you are trying to get the 3.3 V logic level for a generation or acquisition task with the digital lines.
NI USB-621x Specifications
NI USB-621x User Manual
Samantha
National Instruments
Applications Engineer
