Modeling input data that is an integer with a fixed number of digits?

[Costello, Roger L.]

Hello DFDL community,

I want to confirm my understanding of the following DFDL:

<xs:element name="DataEntry"
    type="xs:int"
    dfdl:lengthKind="explicit"
    dfdl:length="2"
    dfdl:lengthUnits="characters"   />

That says the input is an integer that has exactly 2 digits.

Right?

It seems kind of strange to say the length units are characters. It would be 
less strange if I could say the length units are "digits" but that, of course, 
not legal. Any explanation of why length units of characters makes sense?

I reckon the above DFDL is kind of equivalent to the following XML Schema, 
right?

<xs:element name="DataEntry">
    <xs:simpleType>
        <xs:restriction base="xs:int">
            <xs:length value="2" />
        </xs:restriction>
    </xs:simpleType>
</xs:element>