You can use the 13.1072 MHz, 12.8 MHz, 12.288 MHz, and 10.24 MHz timebases to generate data rates. The FD-11637 supports data rates (fs) between 500 Samples/s and 102.4 kSamples/s.

By default, NI-DAQmx automatically chooses the most suitable timebase for a selected data rate. You can also manually select a timebase through the NI-DAQmx API.[1]1 Automatic timebase coercion is supported in NI-DAQmx 18.5 and later. Previous versions of NI-DAQmx use the 12.8 MHz timebase by default. Refer to Timebases and the FD-11637 Specifications for information about choosing the correct timebase for your data rate.

1 Automatic timebase coercion is supported in NI-DAQmx 18.5 and later. Previous versions of NI-DAQmx use the 12.8 MHz timebase by default.