+**parse_payload** - (optional, false by default) if true, the complete payload in the
+ response message will be parsed as a number and returned in the 'value' field of
+ the response. The 'payload' field will be omitted in responses with a
+ 'value'.
+
+**factor** - (optional, 1.0 by default) if `parse_payload` is true, the value in
+ the payload will be multiplied by this factor before returning. The `factor`
+ is applied before the `offset`.
+
+**offset** - (optional, 0 by default) if `parse_payload` is true, this offset
+ will be added to the value in the payload before returning. The `offset` is
+ applied after the `factor`.
+