Yes, simple is best. Converting, calculating etc is ok, though as with a driver a data service should really just be getting raw data from a sensor, decoding it as required and then making sure it is in the correct units (ie observing the usUnits field in the loop packet/archive record you are adding your data to) before adding it to the current loop packet/archive record (a common pitfall is to add temperature data in say F when all the temperatures in the existing packet/record are in C, hence the need to observe usUnits). That way StdConvert, StdCalibrate can do all their converting and calibrating and produce sensible results.
Gary
