IO enables counting.
Start pulse (98% rise) e.g. input voltage on a power supply.
Stop pulse (49% delay and rise) e.g. output voltage on a power supply.
Totalizer counts a clock to measure how long it takes a power supply to startup.
DAC sets the start (e.g. 2V) voltage and stop (e.g. 2.5V) voltage at which timing counts are sent to totalizer.
http://epccs.org/indexes/Board/Totalizer/
