设计FPGA模块模拟自动售货机的工作过程，功能如下（1）售货机有两个进币孔，一个是输入硬币，一个是输入纸币，硬币的识别范围是5角和1 元的硬币，纸币的识别范围是1 元、5 元，10 元，20　　元，50元，100元。乘客可以连续多次投入钱币。（2）顾客可以选择的商品种类有16种，价格分别为1-16元，顾客可以通过输入商品的编号来实现商品的选择。即有一个小键盘（0-9按键）来完成，比如输入15时要先输入1，再输入5。（3）顾客选择完商品后，可以选择需要的数量。然后可以继续选择商品及其数量，每次可以选择最多三个商品。然后显示出所需金额。顾客此时可以投币，并且显示已经投币的总币值。当投币值达到或超过所需币值后，售货机出货，并扣除所需金额，并找出多余金额。在投币期间，顾客可以按取消键取消本次操作，钱币自动退出。-FPGA design module simulates the working process of the vending machine, complete the following functions (1) vending machine has two holes to get the money, one hole for coin, identifying the scope of the coin is 50 cents and $ 1 coins, another is for paper money,recognition range is 1 yuan, 5 yuan, 10 yuan, 20 yuan, 50 yuan, 100 yuan. Passengers can put money more than one chance.　(2) Customers can choose 16 species　of goods, the price of 1-16 yuan, the customer can enter the product number to achieve selection of goods. That there is a keypad (0-9 keys) to complete, for example ,if you choose number 15, you should input number　1　first, and then input number “5”. (3) Once finished selecting the kind of goods, you can　the number you needed. You can then continue to choose the kind and number of goods, and each time can　no more than three kinds of products. Then the machine shows the required price. Now customers can put the money into holes , and the screen shows the total curre