example for reading JSON files

I think you’re looking for something like this:

<AimmsJSONMapping>
    <ObjectMapping>
        <ObjectMapping name="DeviceData">
            <ValueMapping name="minimumMired" maps-to="minimumMired"/>
            <ValueMapping name="maximumMired" maps-to="maximumMired"/>
            <ValueMapping name="numberOfPWMChannels" maps-to="numberOfPWMChannels"/>
        </ObjectMapping>
        <ArrayMapping name="FluxConnectivityTable" iterative-reset="1">
            <ArrayMapping iterative-binds-to="fc1" iterative-reset="1">
                <ValueMapping iterative-binds-to="fc2" maps-to="FluxConnectivity(fc1,fc2)" force-dense="FluxConnectivityDomain(fc1,fc2)"/>
            </ArrayMapping>
        </ArrayMapping>
        <ArrayMapping name="LedParams" iterative-reset="1">
            <ObjectMapping iterative-binds-to="lp1">
                <ValueMapping name="Vf" maps-to="LP_Vf(lp1)" force-dense="LP_VfDomain(lp1)"/>
                <ArrayMapping name="R" iterative-reset="1">
                    <ValueMapping iterative-binds-to="lp2" maps-to="LP_R(lp1,lp2)" force-dense="LP_RDomain(lp1,lp2)"/>
                </ArrayMapping>
            </ObjectMapping>
        </ArrayMapping>
    </ObjectMapping>
</AimmsJSONMapping>

This works together with the following declarations in your model:

DeclarationSection DeviceData {
	Parameter minimumMired;
	Parameter maximumMired;
	Parameter numberOfPWMChannels;
	Set FluxConnectivitySet1 {
		Index: fc1;
	}
	Set FluxConnectivitySet2 {
		Index: fc2;
	}
	Parameter FluxConnectivity {
		IndexDomain: (fc1,fc2);
	}
	Parameter FluxConnectivityDomain {
		IndexDomain: (fc1,fc2);
		Definition: 1;
	}
	Set LedParamSet1 {
		Index: lp1;
	}
	Set LedParamSet2 {
		Index: lp2;
	}
	Parameter LP_Vf {
		IndexDomain: lp1;
	}
	Parameter LP_VfDomain {
		IndexDomain: lp1;
		Definition: 1;
	}
	Parameter LP_R {
		IndexDomain: (lp1,lp2);
	}
	Parameter LP_RDomain {
		IndexDomain: (lp1,lp2);
		Definition: 1;
	}
}

I tested this to work properly with your given input json file, and writing back the data will generate the same json file.

The entries for the “force-dense” attribute are there to make sure that output is also generated when the corresponding identifiers hold default values. They are of no consequence when reading the data.