

At minute top:
If any valve is open, increment its time variable.
if any time var past limit, clear that valve's bit and vars - time and auto flag too
If not, zero that time variable.

If auto is set: (by handle host)
set valve var |= 1 (no effect if already open)

if full - clear valve, variable, time var
unless flow, clear them (figure out how to handle flow outside the plot variable)

if autofill command comes in, open inlet valve and set auto variable.
