me="layers"         type="LayersType"       minOccurs="0" /&gt;
        &lt;!-- used CMSIS-Packs --&gt;
        &lt;xs:element name="packages"       type="PackagesType"     minOccurs="1" /&gt;
        &lt;!-- supported compilers including version --&gt;
        &lt;xs:element name="compilers"      type="CompilersType"    minOccurs="0" /&gt;
        &lt;!-- project build target settings --&gt;
        &lt;xs:element name="target"         type="TargetType"       minOccurs="0" /&gt;
        &lt;!-- components 