1All acceptance devices shall be able to detect the entry of bills, tickets, or vouchers and provide a method, utilizing a bi-directional communication protocol, to enable the slot machine software to interpret and act appropriately upon a valid or invalid input. The bill input system shall be electronically based and constructed in a manner that protects against vandalism, abuse, acceptance of invalid bills, tickets, or vouchers, or other fraudulent activity. Bill acceptance device(s) shall only register credits when the bill, ticket or voucher has passed the point where it is accepted and has been irrevocably stacked.
