== How does the leaky bucket work? ==

A Leaky Bucket is simply an up-down counter for debouncing an input or a fault condition.

=== Leaky Bucket in OpenECU ===

The OpenECU blockset contains a standalone [[doc_user/openecu_user_guide_simulink_chunk/put_leaky_bucket.html|Fault check]] block that can be used for debouncing faults or discrete inputs.  The same leaky bucket algorithm is also used in [[doc_user/openecu_user_guide_simulink_chunk/pax_adc_input_processed.html|Processed Analog Input]] block for built-in fault detection on analog inputs.  This block uses the leaky bucket to detect out of range faults and slew rate faults on the input signal. 

Tips for using this block:
 * The leaky bucket does not just increment the counter by "rise rate" or "fall rate".  The fall rate value is always added to the counter value:
      * If input is true: counter = counter + rise rate - fall rate
      * If input is false: counter = counter - fall rate
 * The rise rate must be greater than the fall rate, or the output will never set.
 * If the hysteresis >= 1, the output will clear as soon as the input clears.
 * If the hysteresis <= 0, the output will stay latched until the ECU is reset.

For a description of the leaky bucket analogy, see [[https://en.wikipedia.org/wiki/Leaky_bucket|Wikipedia's Leaky Bucket Article]].