namely that the frequency option is only there for debugging.
channels.
.TP
\-F SAMPLING_RATE
-Requests the sampling rate for an asynchronous
-acquisition. By default this is set to comedi's highest sampling rate
-so that the driver is forced to reduce it and will in most cases
-return the maximum possible sampling rate.
+Requests a sampling rate for the asynchronous
+acquisition. By default this is set to comedi's highest sampling rate
+(1GHz) so that the driver is forced to reduce it and will
+return the maximum possible sampling rate. This option is only provided
+for driver testing and for drivers which do not return the highest
+sampling rate.
.TP
\-v
Verbose output.