// the below code displays a slider that will control a DMX channel

<form action="{{url}}" method="POST" id="formid">
    <script>
        function update(caller) {
            form = document.getElementById('formid')
            form.caller.value = caller;
            form.submit();
        }
    </script>
    <input type="hidden" name="caller" value="">
    <label for="fader{{channel.attr['id']}}">{{channel.attr['name']}}</label>
    <input type="range" name="fader" id="fader{{channel.attr['id']}}" min="0" max="100" value="{{channel.attr['P']}}" onchange="update('fader{{channel.attr['id']}}')"/>

    // many more channels go here

</form>