/**
@page LEVEL2 Units

The measurement units field for each parameter requires the following syntax:

( <units_spec> )

Each units specification may be a units primitive,
or a combination of units primitives.
A units primitive in the Metric system may also be combined with a prefix to
specify decimal multiples and submultiples, such as mm for millimeters, km for
kilometers, etc.

The rules for combining units primitives are as follows:

<units_product>[/<units_product>[/<units_product>...]] where <units_product> is defined as:

<units_primitive>[2|3][ *<units_primitive>[2|3] [ *<units_primitive>[2|3] ...] ]

Where the units primitives are:

 - @subpage UNITS_TIME "Units of Time"<br>
 - @subpage UNITS_LENGTH "Units of Length"<br>
 - @subpage UNITS_ANGLE "Units of Angle"<br>
 - @subpage UNITS_MASS "Units of Mass"<br>
 - @subpage UNITS_FORCE "Units of Force"<br>
 - @subpage UNITS_ELECTRIC_POTENTIAL "Units of Electric Potential"<br>
 - @subpage UNITS_ELECTRIC_CURRENT "Units of Electric Current"<br>
 - @subpage UNITS_ELECTRIC_RESISTANCE "Units of Electric Resistance"<br>
 - @subpage UNITS_TEMPERATURE "Units of Temperature"<br>
 - @subpage UNITS_GAIN "Units of Gain"<br>
 - @subpage UNITS_ENERGY "Units of Energy"<br>
 - @subpage UNITS_POWER "Units of Power"<br>
 - @subpage UNITS_PRESSURE "Units of Pressure"<br>
 - @subpage UNITS_UNITLESS "Unitless"<br>

@attention Use of \"\--\" is not allowed for any parameter that should have a measurement units specification.

Maximum exponent of 3 is allowed for measurement units.

For example, the following all represent the same units specification:

- m/s2
- m/s*s
- m/s/s

Also, see the following units conversion interfaces:
- @ref Unit "Unit Class"
- @ref UNITS_C_INTF "Units C Interface"
*/