| 摘要 |
PURPOSE:To provide low cost, high performance and high reliability for the POS system. CONSTITUTION:Concerning the POS system composed of three stages of devices of plural POS terminals 1, plural intermediate devices 2 for controlling the plural POS terminals 1 and most significant controller 3 for controlling the plural intermediate devices 2 and provided with a main master 31 at the most significant controller 3, the intermediate devices 2 and the POS terminals 1 are respectively provided with their own masters 21 and 11 and further, a certain means is provided to first search its own master when the POS terminal 1 retrieves the matser and to inquire it to a host device when the relevant key is not discovered at its own master. |
