The sample rate of the built-in Oscilloscope is dynamically adjusted by the horizontal zoom of the display, and can be set up to the full ADC sample rate of 500 MSa/s. Currently you can save 16k points for two channels simultaneously.
For longer term data taking, use the data logging mode. Logging to .CSV is supported at up to 1 kSa/s. For faster data rates use the .li binary format which allows logging to an SD card at up to 100 kSa/s and logging to the Moku:Lab’s RAM at up to 1 MSa/s for single channel and 500 kSa/s for 2 channels.