the invention continually cycles through the u201c no u201d loop until both the card number and the amount of the sale have been entered and buffered however the order or sequence in which these two events occur is not significant after the two events both occur as indicated by block 125 the invention prints the amount entered on display 61 in fig3 and asks whether the amount is correct if so the invention proceeds to call the atm network as usual as indicated by block 130 in this embodiment the user need not be concerned with the order of i swiping the card and ii entering the amount 7 because of the simplicity of the invention it is possible to allow customers to perform part of the billing operation thereby releasing the waiter from several tasks for example when a restaurant patron requests a bill a waiter enters the amount of the patron 39 s bill into the terminal 40 of fig3 as indicated by block 130 in fig9 the invention is designed such that the amount entered by the waiter cannot be changed by the customer as indicated by block 140 for example the terminal 40 can initially display the message u201c enter amount u201d after the amount is entered the terminal displays the message u201c press then to lock u201d when the waiter presses the key and then the key the entered amount is stored into a buffer and cannot be changed thereafter if for some reason the amount must be changed several approaches can be used in one approach a lengthy number sequence can be entered to unlock the terminal 40 alternately the terminal can be programmed such that it remains locked but for a.