If it is a small kind of supermarket , to get a computer,home ordinary computer is also available. 15 inch all in one touch pos is widely use and standard pos hardware (Intel J1900, 2Gram, 32G SSD,windows OS) 

Need to buy a set of cash register software, a barcode scanner, a small ticket receipt printer, a cash drawer. If the scale is slightly larger, then you can add a barcode printer (to facilitate the barcode without barcode goods).

I can give you the best advice regard to pos hardware, if necessary, you can add my whatsapp + 8618938946648, recommend POS supplier Website:http://www.gs-possystem.com.