摘要 |
Systems and methods related to digital frequency locked looping to synchronize frequencies between the local signal from a local oscillator and a reference clock signal from a remote oscillator. A reference counter increments its count for every pulse in the reference clock signal. The value in the reference counter is compared to a configurable reference value. Whenever a match between the reference counter value and the reference value occurs, a hit signal is generated and the reference counter value is reinitialized. Concurrent with the above, a feedback counter increments for every pulse from the local signal. When the hit signal is generated, the value in the feedback counter is compared to a configurable feedback value (by subtraction) to generate a difference value. The difference value is then converted to a frequency adjust signal for use in either increasing or decreasing the frequency of the local oscillator. The hit signal also reinitializes the feedback counter.
|