WO1995017050A1

WO1995017050A1 - Bar code data communication via power lines

Info

Publication number: WO1995017050A1
Application number: PCT/GB1993/002544
Authority: WO
Inventors: Peter Victor Devito
Original assignee: Peter Victor Devito
Priority date: 1993-12-14
Filing date: 1993-12-14
Publication date: 1995-06-22
Also published as: AU5657894A

Abstract

A system in which a central processing unit (44) and a bar code data reading unit (10a, b) are powered from the same power lines (35) and in which transceivers (12a, b) are connected between the respective data input/output ports of the CPU and the bar code reading unit (10a, b) and the power lines (35) to transmit data between them via the power lines (35).

Description

BAR CODE DATA COMMUNICATION VIA POWER LINES

BACKGROUND OF THE INVENTION

This invention relates to a system and method for automated data communication and collection and, in particular, to an interactive system and method for the automated communication and collection of bar code data.

A particular application illustrating the problem faced and solved by applicant will first be discussed to provide greater insight into the nature of the invention. For example, in retail establishments it is desirable.and/or necessary to enable shoppers to ascertain the price of merchandise while they are shopping. This can be achieved by separately marking each item of merchandise in the store, and/or by placing price indicators on the shelves on which the items to be sold are found. These methods are undesirable because they require manual and individualized updating which is time consuming and labor intensive.

A solution to the problem was developed by using a bar code system which entails labelling the items of merchandise with a bar code and then using bar code readers to read the bar code information. The bar code information is transmitted to a computer which is programmed to feed back product pricing and other information to the bar code reader and a display device associated with the bar code reader. A particular system implementation includes bar code readers designed to function as part of price look up (PLU) units distributed throughout a store in convenient locations and at conveniently spaced intervals, with the PLUs being connected via a dedicated cable to a central processor unit (CPU). Shoppers can use the bar code readers of the PLUs to read the bar codes on the goods with the readers being programmed to question the CPU to ascertain the cost of the goods or other pertinent data. By controlling the data input to the CPU, the price of each item in the store can be readily set (or changed) and be made known to the shoppers^* (or the staff of the store) on displays or print-outs associated with the bar code reader, without having to change the labels on the goods or on the shelves. This enables customers to readily check the price of the goods they want to purchase. In the system, the price look up units (PLUs) are powered from the power lines and are hard wired via separate, dedicated, cable to a central computer for data communication. This provides an excellent communication link between the readers and the computer. However, the system presents a significant problem because running interconnecting cables between the PLUs and the CPU throughout the store is very costly. This is particularly so in an already existing and established stores and business establishments which have to be modified. Installing a new set of power lines or interconnecting cables in an existing structure is very expensive. In addition, a problem exists since the operation of the business may be disrupted during the installation of the system.

To overcome the disadvantages and problems associated with running wires, the use of a radio communication system has been suggested, see for example, US patent 5,202,825 titled Transaction Control System Including Portable Data Terminal and Mobile Customer Service Station. However, the patented system is expensive and is also subject to noise signals disrupting its operation. Further, due to radio frequency (rf) interference, radio communication systems are often not useable in certain environments.

It is an object of this invention to overcome these problems and to have an automated data communication and collection system which is inexpensive and easy to install and also dependable.

SUMMARY OF THE INVENTION

Applicant's invention resides, in part, in the recognition that the cost of installing a bar code reading system in a structure, such as a store, warehouse or factory may be significantly reduced by using the power lines which are normally distributed throughout the structure to power the equipment and to also transmit data between various pieces of equipment.^*

Indeed, it is known to have a VOICE BAND (e.g., intercom) system which uses the power lines for propagating signals between various speakers/receivers located at different points along the power lines. However, the voltage levels on power lines are known to be very noisy and subject to sharp voltage changes. Accordingly, power lines are not deemed a suitable conduit for receiving and transmitting data signals in a highly sophisticated electronic systems where the data has to be accurate and where data has to be fed back and forth between a central computer or processor unit (CPU) and other interfacing or peripheral units. Accordingly, these highly sophisticated systems normally require that their components be interconnected via separate and dedicated cables and connections, rather than the power lines. [Note that the term "power lines" as used herein refers to the power lines delivering an alternating current (A.C.), (e.g., 120V, 60 Hz) or even a direct current (D.C.) to power electrically powered equipment and fixtures . ]

■Thus, Applicant's invention resides, in part, ' in the recognition that, by appropriately encoding and decoding the data generated by data readers and a CPU, the very power lines, powering the data readers and the CPU, also can be used to provide the signal (data) paths for a data communication and collection system.

Applicant's invention further resides in the recognition that power lines can be used to transmit and receive bar code data which has been appropriately encoded.

Specifically, Applicant recognized the feasibility of forming an integrated and networking system for communicating bar code information via the power lines between a CPU and units such as bar code readers and/or cash registers located remotely from the CPU and from each other. Such a system may be used in a retail establishment (e.g., a supermarket) or a factory or a warehouse, or any like structure, which includes different working areas which are separated from each other by some distance or are located in different rooms but share the same power line distribution system. In a particular embodiment, Applicant's invention includes a first transceiver connected between a CPU and the power lines and a second transceiver connected between the power lines and a bar code reader. The second transceiver functions to encode the data produced by the bar code reader for transmission via the power lines to the CPU and to decode information received from the CPU via the power lines. The first transceiver functions to decode the information received via the power lines from the bar code reader and for passing the information to the CPU and to encode the information produced by the CPU for transmission via the power lines to the bar code reader and to a display or print-out unit associated with the bar code reader.

BRIEF DESCRIPTION OF THE DRAWING

In the accompanying figures like reference characters denotes like components; and

FIGURE 1 is a simplified lay out of the distribution of power lines in a store;

FIGURE 2 is a simplified idealized system embodying the invention;

. FIGURE 3 is a simplified drawing of. the interconnection of a price look up (PLU) unit and a transceiver; and

FIGURE 4 is a simplified drawing of another system embodying the invention.

DETAILED DESCRIPTION OF THE INVENTION

The system shown in FIGURE 1 illustrates a simplified, typical layout of an electrical power distrubutiσn system throughout a structure. For purpose and ease of illustration the structure is assumed to be a store. However, it should be understood that the structure could be a warehouse, a factory, or any other establishment throughout which a common electrical power system is distributed.

Referring to Figure 1 there is shown a power line 31 coming from the "street" or "main" distribution area into an electric meter and central distribution box 33 from which the electric power is then distributed via power lines 35 to and throughout the structure 37 and 39. For ease of description the structure (37, 39) is partitioned to include a control room 37 and a store or floor space area 39 comprised of aisles or rows running the length and/or width of the store.

The power lines 35 are run about the structure (37 and 39) to provide power for light fixtures 36 and to power electrical appliances located about the store. In addition, power is distributed to outlets 38 provided at regular points along the store space. One aspect of the invention is the recognition that the power line distribution system just described is normally formed as part of the construction of a store, warehouse, factory, or like structures. Therefore, when using existing "power" lines there is little significant additional cost associated with their use. By way of example, Figure 1 shows a control room 37 separated and/or apart from the general store area 39. The control room 37 includes a Central Processing Unit (CPU) 41 and "inputting" and "outputting" (I/O) equipment, 43, associated with the CPU 41 for updating, and/or for reading, the contents of the CPU. Where the structure houses a store, it is assumed that CPU 41 contains all pricing and marketing information pertaining to the goods on sale in the store as well as other pertinent data.

In systems embodying the invention as shown in Figure 2, a CPU 41 is coupled to a transmitter and receiver unit (transceiver) 5 which is coupled via a wall plug 7 to power lines 35. Figure 2 also shows two price look up units (PLUs) 10a and 10b coupled via interface units 11a and lib, respectively, to power lines 35. Specifically, PLU 10a is coupled to transceiver 11a which is' wired to a wall plug 12a designed to be inserted into an electrical outlet 38 located along an aisle of structure 39 as shown in FIG. 1. PLU 10b is likewise coupled to transceiver lib which is wired to a wall plug 12b designed to be inserted into an electrical outlet 38 located along an aisle of the structure 39 as shown in FIG. 1. PLUs 10a and 10b may be located along the same aisle, or in different aisles, of structure 39. Only two PLUs are shown for ease of illustration. However, it is evident that many like units would be, or could be, distributed throughout the structure 39. Normally, transceiver 11a, lib would be selected to be the same and/or to have similar characteristics as transceiver 5, but they need not be the same, so long as they are compatible from a system point of view.

A more detailed view of a PLU 10 is shown in FIGURE 3. A wall plug 12 when mated into wall plug 38 couples the power lines 35 to lines 97a and 97b which function as the input power lines and as the input/output data lines of the PLU 10 and transceiver 11. The AC power signal (assumed to be 115v, 60Hz, but which could be any conventional AC source) present on lines 97a and 97b is applied to a power supply 61 of transceiver 11 which converts the AC power signal into a DC voltage, which DC voltage is applied to, and powers, an encoder/decoder 63. The encoder/decoder 63 functions as the signal interface between the PLU 10 and the CPU 41. Encoder/Decoder 63 receives data information from bar code reader 69 and asynchronous serial driver 67 via data lines 65 and after encoding and formatting the data, it transmits the encoded and formatted data to the CPU 41 via lines 97a and 97b. The encoder/decoder 63 also functions to receive encoded and formatted data information transmitted from the CPU 41 and transceiver 5 via the power lines 35, 97a and 97b and to decode the received information and to then transmit the decoded data via lines 65 to asynchronous driver 67.

The PLU 10 includes a bar code reader 69 for reading or scanning a bar code 190. The bar code reader 69 may be a hand-held laser or CCD scanner, a wand, a fixed mount scanner or any other suitable bar code reading device. The data output of the bar code reader 69 is coupled via data lines 71 to asynchronous serial driver 67. Driver 67 also functions to supply data signals via lines 73 to a display panel 75. Display panel 75 functions to provide a visual indication of the information fed back from the CPU to the PLU. The bar code reader 69, the driver 67 and the display 75 are powered by a DC voltage produced by a power supply 77 which converts the AC power signal present on lines 97a and 97b to a DC voltage.

Bar code scanner 69 is used to read bar code information on a package, or the like, and to produce output information corresponding to the bar code data it has read. The output information may be in any one of a number of formats. In a particular embodiment, the bar code scanner 69 was designed such that the format of the information it produced was in an ASCII code; in addition, the data bits produced on output lines 71 varied between -5 and +5 volts corresponding to an RS2232-C level^*. The data on output lines 71 are supplied to an^' asynchronous serial driver 67 which translates the information it receives from the scanner into data signals varying in amplitude between 0 and 5 volts corresponding to a TTL level. Driver 67 is coupled to transceiver 11 via data input/output lines 65. That is, Driver 67 supplies data from the bar code reader to transceiver 11 via lines 65 and receives data from transceiver 11 via these lines 65. Driver 67 is also coupled via data lines 73 to display panel 75. When information is received from the CPU 41 and coupled via transceiver 11 to Driver 67 the received information is reformatted and coupled to display panel 75 for display. In the embodiment display panel 75 was a 2X20 display. However it should be appreciated that display 75 may be a liquid crystal display (an LCD), or a vacuum fluoresent display (VFD), or a light emitting diode display (LED), or a video monitor, or any suitable piece of display equipment.

In the system of Fig. 3, the data information produced by various pieces of equipment such as PLU 10 is propagated along the power lines 35 to CPU 41. CPU 41 is powered via a wall plug 7b; device 43 which functions to input and output, or monitor, data to or from the CPU may be powered by a wall plug 7c; and transceiver 5 is powered by a wall plug 7a. Data flows between the CPU and power lines 35 via a data path which includes an asynchronous driver 81 coupled to the CPU 41, with driver 81 being coupled to transceiver 5 via data lines 80. Transceiver 5 includes a power supply 82 and an encoder/decoder 83. Power supply 82 receives the AC power signal and converts the AC power signal into a DC voltage to power encoder/decoder 83. Encoder/decoder 83 functions similarly to encoder/decoder 63, in that it receives information from driver 81 and after encoding the received data transmits the encoded information via plug 7a and power lines 35 to the PLUs and other interfacing units connected to the power lines. Conversely, data from the PLUs and interface units received by encoder/decoder

83 is decoded and reformatted and then transmitted via data lines

84 to driver 81 which then feeds the data to CPU 41 via data lines 80.

In a store, to satisfy the requirements of informing purchasers, the operation of the system would be briefly as follows. Typically, a shopper brings a package to the bar code reader 69 and uses the bar code reader to read the bar code data on the package. The bar coded package information is then propagated via lines 71 and driver 67 to transceiver 11 which then encodes the bar code data and renders it suitable for transmission via the power lines 35. The encoded bar code data is then decoded by interface transceiver 5 and reformatted for presentation to CPU 41. The CPU 41 programmed for this application to recognize the product and/or package information and to then provide price information, as well as any other information deemed pertinent. The CPU produced information is then coupled via the bidirectional input/output data lines 80 of CPU 41 to driver 81 and then via data lines 84 to encoder 83 in transceiver 5 which encodes the information and renders it suitable for transmission via the power lines 35. Note that the information produced by the CPU 41 may include more than just pricing information. The actual information being a function of how much and what information the store wishes to provide the shopper and/or have displayed. Anyway, when plug 7a is inserted into outlet 38 the encoded CPU produced information is propagated via the power lines 35. The decoder 63 of transceiver 11 decodes the CPU produced information and formats the information for display on display 75. Note that the display may include a printer and/or any other suitable display device.

The transceivers 5 and 11 may be any of a number of transmitrer-receiver type circuits such as, for example, the PLT-10 Power Line Transceiver Module or the PLC-10 Power Line Control Module, manufactured by the Echelon Corporation, which provide means for coupling networks to the power lines and for transmitting network data onto the power lines. As noted above each transceiver includes circuitry for encoding and formatting information for transmission via the power lines 35 and circuitry for decoding and reformatting information received from the power lines 35.

As already noted, bar code data (e.g., 190) may be read out by a bar code reader (e.g., 69) and then processed by the barcode reader 69 into a suitable data format which data format is then supplied to and further processed by driver circuitry (e.g., 67) and encoder/decoder circuitry (e.g., 63) for transmission onto the power lines. The data format representing the bar code data may be transmitted without significant difficulty since the amount of data typically generated by the bar code reader is typically, but not limited to, 100 bytes per scan or less. The reponse time of the system is faster than can be perceived by a human being. Therefore, the information can be readily transmitted and displayed.

Referring to FIGURE 4, there is shown a PLU 200 which includes a video monitor 210. The video monitor 210 is coupled via a transceiver 211 to a wall plug 12a intended to be inserted into an outlet 38 for connection to the power lines 35. The PLU 200 may be similar to PLU 10a or 10b shown in FIGS. 2 and 3 with appropriate modification for interfacing with video monitor 210. Associated with the video monitor 210 is a video decompression circuit 212 and a local memory 213. To provide a broad range of information to the video monitor 210 from the CPU 41, the system is designed to include a video monitor from the CPU 41, the system is designed to include a video compressor 206 coupled between the data input/output port of CPU 41 and a transceiver 5a to format video and other information into a form suitable for transmission and display by video monitor 210. Data output from CPU 41 is transmitted via video compressor 206 and transceiver 5a onto power lines 35 for distribution to the interface circuits. The CPU 41 supplied data present on power lines 35 is coupled via plug 12a and t-.anεceiver 211 to video decompressor 212 which then causes the data received from teh CPU 41 to be displayed on the video monitor. The information received from CPU 41 via the power lines 35, transceiver 211 and driver 67 is displayed on the monitor 210. Local video memory is provided to maintain the data used for driving the video display monitor when bar code or pricing information is required to be displayed on the video monitor. The previous information is stored in local memory and the data can be instantly refreshed.

By way of example, in a retail establishment, the video monitor 210 may be designed to display a broad range of information and advertising to shoppers while the bar code reader is not activated. In practice the bar code reader is activated, for example, when it is used to read a bar code 190 on a shopper selected product. The bar code information read by the reader is transmitted to CPU 41 as a question or questions regarding the pricing or other pertinent information relative to the product. The CPU is programmed to answer the question(s) and to feed information via a transceiver such as 5a onto the power lines for transmission to the price look up unit and its associated display unit. The information fed back from CPU 41 may then be displayed on the video monitor 210 while other information, such as advertising is inhibited. In the alternative the information fed back from the CPU may be displayed via a split screen or other arrangement of the display together with other general information.

It should be appreciated that where the power lines carry an AC power to the structure, the different phases of the AC power can be used to power the various pieces of equipment and to simultaneously transmit data, as discussed above.

As used herein and in the appended claims the connection(s) of the CPU for transmitting and receiving data are also referred to as the input/output (I/O) port of the CPU. Likewise, the data connection(s) of a transceiver for transmitting and receiving data are also referred to the input/output (I/O) port of that transceiver.

Claims

WHAT IS CLAIMED IS:

1. In a system containing a central processing unit (CPU) and a data reading unit and wherein the CPU and the data reading unit are powered from a set of power lines which extend between the CPU and the data reading unit, and wherein each one of the CPU and the data reading unit has a data input/output port for receiving and emitting data, the improvement comprising; means for powering the CPU and the data reading unit from said power lines; a first transceiver connected between the data input/output port of the CPU and the power lines for transmitting data from the

CPU to the data reading unit along said power lines and for receiving data signals from the data reading unit present on the power lines; and a second transceiver connected between the data input/output

« port of the data reading unit and the power lines for transmitting data to the CPU along said power lines and for receiving data from the CPU present on said power lines.

2. In the system as claimed in claim 1, wherein there is included a plurality of data reading units, each data reading unit having means for coupling the unit to said power lines for receiving its operating power from said power lines, and each data reading unit having a data input/output port, the system including a transceiver per each data reading unit, each transceiver being coupled between the data input/output port of its associated data reading unit and said power lines for transmitting data between its data reading unit and said CPU via said power lines.

3. In the system as claimed in claim 1 wherein the data reading unit includes a bar code reader for reading bar code data and a display unit for displaying information received from the CPU.

4. In the system as claimed in claim 3 wherein the data reading is a price-look-up unit for reading bar code data on selected packages and for determining the cost of the package.

5. In a system as claimed in claim 1, wherein the CPU is located in one working area and the data reading unit ig located in another working area, the two working areas being physically separated while sharing the same power lines.

6. In a system as claimed in claim 1, wherein the data reading unit includes means for reading a bar code for trans ittal to the CPU and means for displaying information received from the CPU, and wherein said second transceiver is coupled between the data input/output port of the data reading unit and said power lines and between said means for displaying information and said power lines.

7. In a system as claimed in claim 5, wherein the data reading unit and the transceiver include power supply means for

17 converting the voltage on said power supply lines to a direct current voltage suitable to power the data reading unit.

8. In a system as claimed in claim 1 wherein each transceiver is coupled to said power lines for receiving its operating power from said power lines.

9. The combination comprising: a set of power lines extending between a first work area and a second work area, physically separated from said first work area; a centra processing unit (CPU) located in said first work area having a data input/output port; a first transceiver located in said first work area coupled between the data input/output port of said CPU and said power lines for passing and distributing data from said CPU to and via said

« power lines and from said power lines to said CPU; a data reading unit located in said second work area for reading data and transmitting said data to said CPU, said data reading unit having a data input/output port; and a second transceiver located in said second work area coupled between the data input/output port of said data reading unit and said power lines for passing data from said data reading unit to said power lines for transmission to said CPU and for passing data supplied to said power lines by said CPU from said power lines to said data reading unit.

10. The combination as claimed in claim 9 wherein said data reading unit includes a bar code reader for reading bar code data.

11. The combination as claimed in claim 10 wherein said data reading unit includes display means and data driving circuitry.

12. The combination as claimed in claim 11 wherein said data driving circuitry is coupled between the bar code reader and said second transceiver.

13. The combination as claimed in claim 12 wherein said second transceiver includes a power supply for producing a dc voltage for operating said second transceiver, and wherein said second transceiver includes means connecting said power lines to said power supply for powering said power supply; and wherein said second transceiver also includes encoding/decoding means and means for connecting said encoding/decoding means to said lines for coupling data signals between said second transceiver and said power lines.

14. The combination as claimed in claim 11 wherein said display means is a video monitor.

15. The combination as claimed in claim 14 wherein said data reading unit includes video decompression circuitry coupled to said video monitor and said CPU includes video compression circuitry.

16. The combination as claimed in claim 15 wherein said data reading unit includes a local memory coupled to said video monitor.