Nowadays snack and drink machine demands is increasing to satisfy customer needs and are a valued addition to any environment, for both customer and operator. Objective is to design a fully automatic snack and drink machines using the PLC ladder logic. Design a PLC program to get one of the can drinks or snacks show $n$ in the machine. Machine only accepts visa card. To use a vending machine, after you choose a snack$/$drink and pas the cost of the product, the selected snack of choice falls down. Basic information about the design$/$machine are as follows:

$-$The machine only accepts Visa card and will reject if there is no enough money in the card.

Machine has key in button options$($numbers$)$ to choose the drinks or snacks

The machine has $9$ snack options and $18$ drink options. But each transactior you can only either choose snack or drink. Each snack or drink has code of two$-$digit numbers.

$-$Machine should fill to snack$/$drink whenever one snack or drink is used.

The customer takes the ready drink or snack from the allocated slot in the machine when it is ready.

The machine should inform the customer if there is an error in the machine

This vending machine is simple and small size.