Serial data conversion

#The present invention relates generally to a method of and apparatus for converting serial data from one format to another.

#It is known in the art to transmit serial data from a computer system to a printer thereby causing the printer to print. For example, as shown in FIG. 1, in retail establishments a register or checkout terminal, such as a terminal 100 at a checkout lane 102 of a retail establishment, has an attached printer 104 for printing a receipt for a customer 106. Typically, printer 104 is attached using a serial line, e.g., an RS-232 connection, data line to terminal 100. In normal use, customer 106 provides an item 108 to a checkout operator 110 who rings up the item 108 at terminal 100 and requests payment from customer 106. Upon receiving payment and providing change, if appropriate, checkout operator 110 manipulates keys on a keyboard 112 attached to terminal 100 causing a receipt 114 to be printed at attached printer 104. In an alternate self-service embodiment, customer 106 interacts directly with a modified version of checkout lane 102 to ring up items and tender payment without needing a checkout operator 110.

#More specifically, during the transaction, checkout operator 110 enters information about item 108 to be purchased by customer 106, e.g., by scanning a bar code 118 on item 108 using a bar code scanner 116 to obtain item information or entering pricing, bar code 118 or other information using keyboard 112. As checkout operator 110 enters information, terminal 100 maintains a cumulative total for item 108 to be purchased by customer 106. Terminal 100 may also maintain a list of items including item identifying information, e.g., brand and quantity, and item price to be purchased by customer 106.

#The present invention is illustrated by way of example, and not by limitation, in the figures of the accompanying drawings, wherein elements having the same reference numeral designations represent like elements throughout and wherein:

#FIG. 1, as previously described, is an illustration of one way the method of the invention can be practiced in a purchasing environment;

#FIG. 2, also previously described, is a high level block diagram of a configuration of a prior art promotion receipt printer;

#A method and apparatus for receiving USB-based print commands and converting the USB-based print commands to serial-based print commands at a printer are described. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent; however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the present invention.

#Top Level Description

#An existing USB-based printer is modified to enable the conversion of USB-based printing commands to serial-based print commands. The serial print commands are then transmitted to an existing line detection unit for detection and, when appropriate, generation of print commands to be transmitted to an existing serial promotional receipt printer.