(Maitre'D 2003, from Service Pack 6 and later versions of Maitre'D)
P.O.S. Control / View / Options / POS
We improved the on screen calculator feature to allow the use of the plus
(+) button on the promotion amount entry screen to add multiple instances
of the same discount, similarly to the calculator feature for media types.
To make this function available, activate the following option:
Enable Media Screen Calculator
For example, if you have 2 coupons of different amounts, you can use the
plus button to add them together and enter a total amount of discount,
instead of manually adding 2 amounts before entering their total at the
workstation.