The required count attribute is the number of unsigned byte values in this array.
Source
<xs:complexType name="ArrayUnsignedByteType"><xs:annotation><xs:documentation>The ArrayUnsignedByteType is an array of unsigned byte values.</xs:documentation></xs:annotation><xs:simpleContent><xs:extension base="ListUnsignedByteType"><xs:attribute name="count" type="NaturalType" use="required"><xs:annotation><xs:documentation>The required count attribute is the number of unsigned byte values in this array.</xs:documentation></xs:annotation></xs:attribute></xs:extension></xs:simpleContent></xs:complexType>
<xs:attribute name="count" type="NaturalType" use="required"><xs:annotation><xs:documentation>The required count attribute is the number of unsigned byte values in this array.</xs:documentation></xs:annotation></xs:attribute>