Casio qt 6600 - Gross/Net sales and free function query

Hi guys,

I have a bunch of qt 6600 tills along with the back office system in my business and for years free functions such as comps, staff drinks and wastage have been recorded as NIL and totalled up in reports. At the moment this means Gross and Net sales on reads would be the same even if plenty of free functions recorded. How can I programme the tills to reverse this so that the free functions are recorded at full price in the gross and net sales so that the gross includes all sales at full price including all free function transactions and then net sales has the actual cash taken is the net figure on x and z reads then.

In summary, I'm looking for Gross sales to include every transaction at full sales price and Net sales to be the bottom line cash taken.

If anyone can offer some advice on this issue, I'd appreciate it.

Thanks