                             tangojs.tango.AttrWriteType.READ_WRITE,
                             undefined,
                             undefined,
-                            null)
+                            null,
+                            tangojs.tango.AttributeDataType.ATT_STRING)
     sine_trend: (->
       name = 'sine_trend'
       format = 'scientific,setprecision(3)'

                            new tangojs.tango.AttributeAlarm({
                              max_warning: '50'
                              max_alarm: '70'
                            }))
    string: createAttribute(undefined,
                            'string'
                            undefined,

                             tangojs.tango.AttrWriteType.READ,
                             undefined,
                             undefined,
                             null,
                             tangojs.tango.AttributeDataType.ATT_DOUBLE)
      attr.get_value = ->
        value = Math.sin((new Date()).getTime()/1000.0)
        createDeviceAttributeStruct(name, format, value)
