You say this is a PoS (I'm assuming you mean Point of Sale and not Piece of S**t).
A previous job of mine was a manager at a new start-up resturant. I worked closely with the PoS guys, so if something went wrong I could fix it on the spot.
Through this, I became very familiar with PoS's.
If there is any thousandth's decimal, most, if not all, PoS's will always round up - why? Money. Those fractions of a penny add up after a full day of sales. So if it didn't round up, the business could potential take a big hit, think 200 orders a day, each with .004 cents cut from that is .80 cents. .80 cents a day is $292 dollars a year - and that's thinking very conservatively.
For example, have you ever seen Office Space? It is the same principal.
Now as for your question, I'm not completely sure what you are asking...
Last edited by TFlan; 01-10-2013 at 12:05 AM..