Single Button Price Preset

Hi everyone

I'm looking for a cash register & need some advice...

Can someone tell me if the department buttons that appear to be on a lot of cash registers can be programmed as a single fixed price button?

We need this ability for a till to be used for customers attending an event.

For example - could we programme a till for say three buttons - adult - child - family. Then all we would need to do is press adult three times for three adults - child twice for two children etc...

I think I read somewhere that the department buttons on some tills could be programmed in this way instead of being a department button.

Can anyone advise?

Thanks!