This information is part of the Modelica Standard Library maintained by the Modelica Association.

Enumeration defining the resolution of a clock signal, especially of the clock signal generated by block PeriodicExactClock. The following values are possible:
 

Types.Resolution.	Meaning
y	year (= 365*24*60*60 seconds)
d	day (= 24*60*60 seconds)
h	hour (= 60*60 seconds)
m	minute (= 60 seconds)
s	seconds
ms	milli seconds (= 1/1000 seconds)
us	micro seconds (= 1/(1000*1000) seconds)
ns	nano seconds (= 1/(1000*1000*1000) seconds)

y	y (year)
d	d (day)
h	h (hour)
m	min (minutes)
s	s (seconds)
ms	ms (milli seconds)
us	us (micro seconds)
ns	ns (nano seconds)