Inventors:
Jerald C. Curtis - Wellington CO
International Classification:
G06F 1520
Abstract:
A signaling method and apparatus is described for obtaining a compact but high-resolution and wide-range digital representation of the frequency or period of an input signal. A reference frequency is counted over a number of cycles of the input signal by a counter having a nonlinear response so that the digital representation provided by the counter's value has a relatively high resolution over a wide range. The nonlinear response is provided by selectively dividing the reference frequency in response to the counter's value to obtain a clocking signal for the counter. A minimum resolution is preferably insured by requiring the counter to register a predetermined minimum number of counts before a frequency-indicating value is sampled by a latch. A predetermined function is applied to the sampled value to obtain the approximate number of counts that the counter would have registered but for the selective division of the reference frequency. The relative frequency of the input signal is equal to the number of cycles of the input frequency over which counting occurs divided by the number of counts that the counter would have registered.