Automatic frequency prescaler

A method implemented in a test and measurement instrument, the method comprising:

• receiving an input signal via an input;
• generating an event signal when an event occurs in the input signal;
• iteratively determining an estimated signal frequency of an event signal indicating events in the input signal;
• automatically selecting a divide ratio, corresponding to a divider circuit, for the event signal based on the estimated signal frequency such that the selected divide ratio scales the event signal by a predetermined integer value for signal processing by the test and measurement instrument;
• determining a number of trigger events in the event signal and outputting a frequency of the event signal based on the determined number of the trigger events;
• determining an elapsed time result based on the number of trigger events;
• and
• employing the elapsed time result to determine the estimated signal frequency.

A non-transitory computer readable medium having stored thereon a computer program product for execution by a processor configured to perform test and measurement, the computer program causing the processor to perform a method comprising:

• receiving an input signal via an input;
• generating an event signal when an event occurs in the input signal;
• iteratively determining an estimated signal frequency of an event signal indicating events in the input signal;
• automatically selecting a divide ratio, corresponding to a divider circuit, for the event signal based on the estimated signal frequency such that the selected divide ratio scales the event signal by a predetermined integer value for signal processing by the test and measurement instrument;
• and
• determining a number of trigger events in the event signal and outputting a frequency of the event signal based on the determined number of the trigger events;
• determining an elapsed time result based on the number of trigger events;
• and
• employing the elapsed time result to determine the estimated signal frequency.