Main parts of electronic cash register

Electronic cash register structure consists mainly of electronic devices and mechanical components of the second category, there are seven components:
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1) Motherboard - central data processing components

2) memory --- store information, data, procedures

3) keyboard --- used to enter a variety of sales data

4) Printer --- used to print sales invoices and management stubs

5) display --- for the convenience of cashiers and customers for man-machine dialogue

6) Cash box --- for cash receipt cash

7) External device interface --- used to connect a variety of external devices