FIELD OF THE INVENTION
[001] The present invention generally relates to a system for changing content orientation of display devices positioned in one or more panels, and more particularly, but not exclusively, to a system and method for changing content orientation of display devices in one or more panels by a remote terminal or by at least one of the display device of the one or more display devices which are positioned in at least one of the one or more panels.
BACKGROUND OF THE INVENTION
[002] All monitoring devices (e.g. display devices) installed in a panel can be mounted only in one direction as defined by the manufacturer. The monitoring device includes a display for displaying the monitored information. It is not necessary that terminal blocks of all monitoring devices to be installed in a panel should come with same orientation or design .This makes the routing of wires more complex to match with the layout of panels and maintenance is also difficult. The complex internal wiring diagram with one or more monitoring devices positioned in a panel as shown in figure 1A. Figure IB illustrates a front view of the panel corresponding to the monitoring devices positioned in a panel as per figure 1A One possible solution to solve this problem is to position the monitoring device in the panel by rotating the device as per panel structure with optimum wire routing and then change orientation of displayed content as per viewing orientation. Figure 2A illustrates positioning of mounting devices with optimum wire routing by rotating the device and figure 2B illustrates the corresponding panel front view.
[003] Different methods are available to change the orientation of content displayed in the monitoring devices (e.g. display devices) as listed below

(i) Changing the orientation manually
Human intervention is required to operate switches positioned in the display devices to changes the orientation. In high voltage environment, the human intervention to display devices is not advisable from operator safety point of view. Operator has to change orientation of the monitoring devices one by one manually .Whenever new devices are added to the system same procedure has to be followed. Landscape and portrait modes are addressed, where number of rows per screen change between two modes and this is not applicable for mounted devices, parameter value and units should be in same row
(ii) Automatic orientation changes whenever the display device detects change in mounting orientation with the help of sensors
Implementing sensor in each device is not cost effective solution, since the number of times monitoring device changes its orientation in its lifetime is very limited, in general only once after installation, orientation change is required. Landscape and portrait modes are addressed, where number of rows per screen change between two modes and this is not applicable for mounted devices, which changes the original viewing experience of the display, parameter value and units should be in same row
[004] Accordingly there is a need in the art to provide a solution to one or more of above said problems. The present invention solves one or more of these problems in a unique and economical manner.
SUMMARY OF THE INVENTION
[005] It is a feature of the present invention to provide a system which substantially overcomes the one or more of the above mentioned disadvantages.

[006] It is the principal objective of the present embodiment is to provide a system and method for changing the content orientation of the one or more display devices positioned in the one or more panels from the remote terminal.
[007] Another objective of the present embodiment is to provide the system and method for changing the content orientation of the one or more display devices positioned in the one or more panels or the one or more display devices positioned in the same panel using at least one of the one or more display devices.
[008] In one aspect, a system for changing content orientation of a first set of display devices positioned in a first panel and a second set of display devices positioned in a second panel is provided. Each of the first set of display devices and the second set of display devices includes a master display device and at least one slave display device. The system includes an orientation sensor positioned at the master display device to detect orientation of the master display device, and a remote terminal that (i) generates a first orientation change signal and transmits to the display devices positioned in at least one of the first panel and the second panel when (a) event occurs in the remote terminal eg: when control button in the remote terminal is activated or (b) a third orientation change signal received from at least one of the first set of display devices or the second set of display devices. Each of the first set of display devices and the second set of display devices includes a control unit. The control unit of the master display device (i) receives the first orientation change signal from the remote terminal, (ii) generates a control signal based on the orientation detected in the orientation sensor and a one or more categories associated with the first set of display devices and the second set of display devices and the lookup table, and (iii) transmits the control signal to the at least one salve display device positioned in at least one of the first panel and the second panel and to the remote terminal.
[009] The control unit of all devices receives the control signal and changes the content orientation of the first set of display devices and the second set of display devices based on the control signal. The control unit stores (i) at least one of the one or more categories associated

1*
with each of the first set of display devices and the second set of display devices and (ii) a lookup table which comprises a different combinations of the one or more categories and a one or more view orientation for each of said first set of display devices and the second set of display devices. Each of the first set of display devices and the second set of display devices comprises a one or more control buttons which allows a user to transmit the third orientation change signal to the remote terminal for changing the content orientation of (a) the second set of display devices from at least one of the first set of display devices and (b) the first set of display devices from at least one of the second set of display devices. The one or more control buttons provided in each of the first set of display devices and the second set of display devices allow user to transmit a third orientation change signal to the master display device positioned in at least one of (i) the first panel from the first set of display devices and (ii) the second panel from the second set of display devices for changing the content orientation with in the same panel.
[0010] First orientation signal is the signal sent by the remote terminal to the one or more panels in the system and the master display device positioned in the one or more panel receives and processes the first orientation change signal. Second orientation signal is the signal sent by at least one of slave display devices positioned in at least one of the one or more panels to the master display devices positioned in the panel. Third orientation signal is the signal sent by one or more display devices in the one or more panels to a remote terminal for changing the content orientation of one or more display device positioned in the other panel.
BRIEF DISCRIPTION OF THE ACCOMPANYING DRAWINGS
[0011] The advantages and features of the invention will become more clearly apparent from the following description which refers to the accompanying drawings given as non-restrictive examples only and in which:
[0012] Figure 1A illustrates a typical panel with one or more monitoring devices positioned in default orientations;

[0013] Figure IB illustrates a front view of the typical panel of figure 1A;
[0014] Figure 2A illustrates a typical panel with one or more monitoring devices and uses a typical approach to change the orientation of one or more monitoring devices;
[0015] Figure 2B illustrates a front view of the typical panel of figure 2A;
[0016] Figure 3 illustrates a system for changing content orientation of one or more display devices positioned in the one or more panels in accordance to a preferred embodiment herein;
[0017] Figures 4A-4D illustrates different categories of the one or more display devices in accordance to the preferred embodiment herein;
[0018] Figures 5A-5B illustrates a system for changing the content orientation of the one or more display devices positioned in the first panel of figure 3 in accordance to the preferred embodiment herein;
[0019] Figures 6A-6C illustrates a method for controlling the content orientation of the one or more display devices in the one or more panels from at least one of the one or more display devices in accordance to the preferred embodiment herein; and
[0020] Figures 7A-7C illustrates a method for changing the content orientation of the one or more display devices in the one or more panels from a remote terminal or from at least one of the one or more display devices in accordance to the preferred embodiment herein.
DETAILED DISCRIPTION OF THE INVENTION

[0021] The present invention will be described herein below with reference to the accompanying drawings. A system and method for changing the content orientation of one or more display devices in the one or more panels is described.
[0022] The following description is of exemplary embodiment of the invention only, and is not limiting the scope, applicability or configuration of the invention. Rather, the following description is intended to provide a convenient illustration for implementing various embodiments of the invention. As will become apparent, various changes may be made in the function and arrangement of the structural/operational features described in these embodiments without departing from the scope of the invention as set forth herein. It should be appreciated that the description herein may be adapted to be employed with alternatively configured devices having different shaped, components, and the like and still fall within the scope of the present invention. Thus the detailed description herein is presented for purposes of illustration only and not of limitation.
[0023] The present embodiment provides a display device, and more particularly, the embodiment relates to the system and method for changing the content orientation of the one or more display devices positioned in the one or more panels. The display devices are referred herein and exemplified as metering devices in the figures. However, the display devices may comprise any kind of display devices which displays the content to the user.
[0024] Figure 3 illustrates a system 300 for changing content orientation of one or more display devices 304An-Bn positioned in the one or more panels 302A-B in accordance to a preferred embodiment herein. A system 300 includes one or more display device 304An-Bn positioned in one or more panels 302A-B, a remote terminal 308 and one or more orientation sensors 306A-B. The first set of display devices 304Al-n positioned in the first panel 302A, a second set of display devices 304Bl-n positioned in the second panel 302B. The one or more panels 302A-B, one or more display devices 304An-Bn and the remote terminal are connected in wired or wireless communication network. In this preferred embodiment, the Control Area Network (CAN) is used for connecting the one or more panels 302A-B, one or more display

devices 304An-Bn and the remote terminal 308. Communication is not limited to CAN network, any communication network can be used to achieve the same (Mod bus, Ethernet etc). Each of the first set of display devices 304Al-n and the second set of display devices 304Bl-n includes a master display device 304A1, 304B1 and one or more slave display devices 304A2-n, 304B2-n. The one or more orientation sensors 306A-B are positioned at the master display device 304A1, 304B1 to detect an orientation of the master display device 304A1, 304B1. Each of the one or more display device 304An-Bn and remote terminal includes a control unit (not shown in Figure 3) which includes a memory unit for storing the look-up table and a category of the display device. The look-up table includes different combinations of possible orientations for the different categories of the one or more display devices 304An-Bn and the default orientation of all devices provided by manufacturer is labeled as '1'. The remote terminal further includes a master bus controller 312 which is responsible for sending the first orientation change signal to the one or more display devices 304An-Bn positioned in the one or more panels 302A-B through the bus 314A-B.
[0025] Figures 4A-4D illustrates different categories of the one or more display devices in accordance to the preferred embodiment herein. In the figures 4A-4D, four types of categories are illustrated. For example, the figure 4A illustrates 'A' category display device, figure 4B illustrates 'B' category display device respectively. The categories associated with each of the one or more display device is stored in the control unit while manufacturing the display devices. The look-up table is generated and stored in the memory unit of each of the one or more display devices 304An-Bn when manufacturing the display device or before installing the one or more display devices 304An-Bn in the one or more panels 302A-B. The example look-up table for the one or more display devices 304An-Bn shown in the figure 4A-4D is given in below table I. For example ,in a particular panel, category 'A' device's correct orientation is ' 1' ,it implies that category 'B' device should in orientation '2' ,'C should be in '3' and D should be in '4\A11 devices connected in a network should agree upon common standard for device category and orientation lookup table which is included in product firmware.

[0026] Figures 5A-5B illustrates a system 300 for changing the content orientation of the first set of display device 304A1-4 in the first panel 302A from the remote terminal 308 in accordance to the preferred embodiment herein.
[0027] In one scenario, the user requires to change the content orientation of the first set of display devices 304Al-n in the first panel 302A from the remote terminal 308. The remote terminal 308 sends the first orientation change signal on the bus 314A and the master display device 304A1 positioned in the first panel 302A receives the first orientation change signal. The control unit of the master display device 304A1 generates a control signal based on the category associated with the master display device 304A1, the look-up table and an orientation (e.g. view orientation) detected in a first orientation sensor 306A, when the first orientation change signal received from the remote terminal 308. For example, the orientation sensor 306A detected that the view orientation of the master display device 304A1 is T and the device category of the master display device 304A1 is 'C, then the control unit of the master display device 304A1 generates a control signal as follows A3B4C1D2. The control unit of the master display device 304A1 changes its orientation based on the control signal and transmits the control signal in a broadcast manner to the one or more slave display devices 304A2-n in the first panel 302A and to the remote terminal. The remote terminal saves this information for future processing. The control unit in each of the one or more slave display devices 304A2-n decodes the control signal and changes the content orientation of the one or more slave display devices 304A2-n accordingly. For example the display device 304A2 belongs to D category

' f
and it is installed in the default view orientation ' 1', and based on the control signal the control unit of display device 304A2 changes its view orientation '2' from the default view orientation
T.
[0028] In another scenario, the user requires to change the content orientation of the first set of display devices 304Al-n in the first panel 302A and the second set of display devices 304Bl-n in the second panel 302B simultaneously from the remote terminal 308. The remote terminal 308 sends the first orientation change signal on the 314A-B to the master display device 304A1 positioned in the first panel 302A and the master display device 304B1 positioned in the second panel 302B. The control unit of the master display device 304A1-B1 generate a control signal based on the category associated with the master display device 304A1-B1, the look-up table and an orientation (e.g. view orientation) detected in a orientation sensor 306A-B, when the first orientation change signal received from the remote terminal 308. For example, the orientation sensor 306A detected that the view orientation of the master display device 304A1 is T and the device category of the master display device 304A1 is 'C, then the control unit of the master display device 304A1 generates a control signal as follows A3B4C1D2 and the orientation sensor 306B detected that the view orientation of the master display device 304B1 is '2' and the device category of the master display device 304A1 is 'A', then the control unit of the master display device 304B1 generates a control signal as follows A2B3C4D1 . The control unit of the master display device 304A1-B1 changes its orientation based on the control signal and transmits these two generated control signals to the one or more slave display devices 304A2-n in the first panel 302A and to the one or more slave display devices 304B2-n in the second panel 302B and to the remote terminal 308 independently on the bus 314A and 314B. The remote terminal 308 saves these two control signals for future processing. The control unit in each of the one or more slave display devices 304An-Bn decodes the control signal and changes the content orientation of the one or more slave display devices 304An-Bn accordingly. For example the display device 304A2 belongs to D category and it is installed in the view orientation '1', and based on the control signal (A3B4C1D2) the control unit of display device 304A2 changes its view orientation '2' from the view orientation

' 1'. The display device 304B2 belongs to device category 'B' and it is installed in default view orientation T and based on the control signal (A2B3C4D1) the control unit of display devicr 304B2 changes its orientation to '3' from default orientation ' 1'.
[0029] Figures 6A-6C illustrates a method for changing the content orientation of one or more display devices 304An-Bn in the one or more panels 302A-B from the at least one of the display device in accordance to the preferred embodiment herein. Each of the one or more display devices 304An-Bn includes a display 602 and the a first set of control buttons 604A for menu selection and a second set of control buttons 606B for navigating the options displayed in a menu. The first set of control buttons 604A and the second set of control buttons 604B facilitates the user to select at least one option 606, 608 and 610 from provided in the menu (shown in Figure 6B & 6C) which is displayed in the display 602. The menu also provides the options such as (i) change orientation of this device option 608, and (ii) change orientation of the device in the network option 610.
[0030] In one scenario, the user chooses the option 608 from the menu. The option 608 allows the user to change the content orientation of the display device 304 to a different view orientation based on the look up table stored in the display device. For example, the display device 304 is associated to 'A' category and by default the display device is in view orientation ' 1' and if the user wish to change the orientation then the control unit of the display device checks the other possibilities of other view orientations available for the 'A' category display device and changes the view orientation of the display device according to at least one of the different view orientations available in the look-up table. For example, in the look up table the next possible view orientation is '2' then the control unit changes the content orientation of the display device 304 to a view orientation to '2'., the display shows the different view orientation available for the display device 304 in thumbnail view and allows user to select the view orientation using the second set of buttons 604B.
[0031] In another scenario, the user chooses the option 610 from the menu. This option 610 allows the user to change the content orientation of the display device 304 positioned in

the one or more panels 302A-B. For example, the display device 304 is master display device 304A1 which is positioned in the first panel 302A and upon choosing the option 610 the display 602 displays the one or more of panels 302A-B available in the network and allows the user to select the panel which he wants to change the content orientation of the one or more display devices 304An-Bn. For this preferred embodiment, the display 602 shows (i) first panel and (ii) second panel, hence the system 300 includes only the two panels 302A-B.Same concept can be applied to any number of panels in the network If the user selects the first panel then the control unit of the master display device 304A1 generates the control signal and transmits to the one or more slave devices 304A2-n positioned in the first panel 302A. If the user selects the option second panel then the control unit of the master display device 304A1 sends the orientation change signal (e.g., third orientation change signal) to the remote terminal 308 and the remote terminal 308 decodes the orientation change signal and sends the orientation change signal (e.g. first orientation change signal) to the second panel 302B. In another example, the display device 304 is the salve display device 304A2 and if the user selects the option i.e. first panel then the control unit in the display device sends the orientation change signal (e.g. second orientation signal) to the master display device 304A1.
[0032] In another scenario, newly added devices in the network can request master display devices for orientation change signal without human intervention and the master display device responds to the request by sending orientation control signal. In yet another scenario, upon receiving third orientation change signal, remote terminal 308 decodes the message and converts this ,message in a way that is compatible with other panel structures and transmits this signal on the bus 314A-B.This doesn't require involvement of master display device 304A1-B1 in the network
[0033] Figures 7A-7C illustrates a method for changing the content orientation of the one or more display devices 304An-Bn in the one or more panels 302A-B from a remote terminal 38 or from at least one of the one or more display devices 304An-Bn in accordance to the preferred embodiment herein. In step 702, the first orientation change signal is received at the master display device 304A1-B1 from the remote terminal 308 through the bus 314A-B. In

■
step 704, the orientation of the master display device 304A1-B1 is detected using the orientation sensors 306A-B. In step 706, the control signal is generated in the control unit of the master display devices 304A1-B1 based on the orientation and the look-up table stored in the control unit. In step 708, the control signal is transmitted to the one or more slave display devices 304A2-n and 304B2-n. In another preferred embodiment, the method for changing the content orientation one or more display device 304An-Bn positioned in the one or more panels 302A-B from the at least one of the one or more display devices 304An-Bn is shown in Figure 7B. In step 710, the second orientation change signal is received in the master display device 304A1 from the at least one of the one or more slave display devices 304A2-n. In step 712, the control unit of the master display device 304A1 generates the control signal based on the orientation sensed in the orientation sensor 306A and the look up table. In step 714, the control signal is transmitted to the one or more slave display devices 304A2-n from the master display device 304A1.
[0034] In yet another preferred embodiment, the method for changing the content orientation of the one or more display devices 304An-Bn positioned in the one or more panels 302A-B is shown in figure 7C. In step 716, the remote terminal 308 receives the third orientation change signal from the at least one of the one or more display device 304An-Bn. In step 718, the remote terminal 308 generates the first orientation change signal based on the third orientation change signal and transmitting the first orientation change signal to the one or more panels 302A-B. In step 720, The master display device 304A1-B1 receives the first orientation change signal and generates the control signal. In step 722, the control signal is transmitted to the one or more slave display devices 304A2-n, 304B2-n.
[0035] CAN is a multi-master broadcast serial bus standard for connecting electronic control units (ECUs). Each node is able to send and receive messages, but not simultaneously. A message consists primarily of an ID (identifier), which represents the priority of the message, and up to eight data bytes. It is transmitted serially onto the bus. This signal pattern is encoded in non-return-to-zero (NRZ) and is sensed by all nodes. In the system 300 shown in

figure 3, the one or more display devices 304An-Bn positioned in the one or more panels 302A-B and the remoter terminal are connected through the CAN via the bus 314A-B.
[0036] When message (e.g. control signal) for orientation change is sent on the bus 314A-B, all devices 304An-Bn connected in a network receive the message, filter the message and change orientation accordingly to the mechanism mentioned in lookup table.
[0037] CAN protocol is a message-based protocol, not an address based protocol. This means that messages are not transmitted from one node to another node based on addresses. Embedded in the CAN message itself is the priority and the contents of the data being transmitted. If the bus 314A-B is free, any node may begin to transmit. If two or more nodes begin sending messages at the same time, the message with the more dominant ID (which has more dominant bits, i.e., zeroes) will overwrite other nodes' less dominant IDs, so that eventually (after this arbitration on the ID.) only the dominant message remains and is received by all nodes. This mechanism is referred to as priority based bus arbitration. Messages with numerically smaller values of IDs have higher priority and are transmitted first.
[0038] All nodes in the system 300 receive every message transmitted on the bus 314A-B (and will acknowledge if the message was properly received). It is up to each node in the system to decide whether the message received should be immediately discarded or kept to be processed.
[0039] A single message can be destined for one particular node to receive, or many nodes based on the way the network and system are designed. Based on this, we can control text orientation of one or more display devices 304An-Bn (e.g. multiple meters) simultaneously or any particular meter.
[0040] Different types of products can be connected to each other via CAN BUS in a similar fashion. Even the base communication of the device is not CAN, It can be connected to CAN network bus using converters.

*
[0041] CAN protocol with broadcasting and multicasting possibilities. These possibilities are a great strength of CAN as they reduce the amount of communication needed in a system. Furthermore all nodes will get the same information simultaneously with the CAN protocol and this feature is valuable in Controller Area Networks where the nodes have to work in a synchronized way.
[0042] Current invention uses these important features of CAN protocol. After devices 304An-Bn are installed in the panels 302A-B, operator can initiate orientation control (either from remote terminal 308 outside panel 302A-B or one of the devices 304An-Bn positioned inside the panels 302A-B depending on accessibility). Remote terminal 308 transmits first orientation change signal, which will be processed by master devices 304A1, 304B1 in the panels 302A, 302B as explained in earlier sections. All nodes in a network receive this message, filter the message and change the orientation if required as per the received message. To do this job, all devices should agree up on common algorithm for orientation management, which is defined at higher protocol layers.
[0043] Generally data transmission is performed with the data source node sending out a Data Frame. It is also possible, however, for a destination node to request the data from the source by sending a remote frame. Any device in the network can respond to this by sending orientation DATA FRAME. Even if some devices are down in the network, devices which are alive can send DATA FRAME.
[0044] If orientation data frame is issued by the remote machine at the same time, since the identifier is same the Data Frame wins arbitration due to the dominant RTR bit following the identifier. In this way, the node that transmitted the Remote Frame receives the desired data immediately
[0045] When devices are added to the network, one or all can ask for Orientation DATAFRAME .DATAFRAME will be sent by one or all the devices in the network (in case

some of the devices issue overload frame) .Since DATAFRAME (REMOTE FRAME) is sent by all devices is same, no collision of data happens .Since it's a broadcast communication all devices receive DAT FRAME and process it .It's not necessary that all newly added devices should send REMOTE FRAME. Whenever devices are added or deleted from the network, no effect on already configured devices.
[0046] The present embodiment facilitates to provide the system and method for changing the content orientation of the one or more display devices positioned in the one or more panels. The system includes a remote terminal which sends the orientation change signal to at least one of the one or more panels. Each of the one or more panels includes a master display device that includes the orientation sensor and one or more slave display devices. The master display device receives the orientation change signal from the remote terminals, generates a control signal and transmits the control signal to the one or more slave display devices positioned in the panel. Further, the present embodiment also facilitates to change the content orientation of the one or more display devices positioned in the one or more panels or one or more display devices positioned in the same panel using at least one of the one or more display devices. It can be noted that in multi master protocol any device can act as master.
[0047] Several exemplary embodiments have thus been described. Modifications and alterations may occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiments be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
We claim:
1. A system (300) for changing a content orientation of a first set of display devices
(304A1-n) positioned in a first panel (302A) and a second set of display devices (304B1-n)
positioned in a second panel (304A), wherein each of said first set of display devices and said
second set of display devices comprises a master display device (304A1, 304B1) and at least
one slave display device (304A2-n, 304B2-n), said system comprising:
an orientation sensor (306A, 306B) positioned at said master display device (304A1, 304B1) to detect an orientation of said master display device; and
a remote terminal (308) that (i) generates a first orientation change signal and transmits to said master display device positioned in at least one of said first panel and said second panel when (a) event occurs in said remote terminal or (b) a third orientation change signal received from at least of said first set of display devices and said second set of display devices;
wherein each of said first set of display devices and said second set of display devices comprises a control unit; said control unit of said master display device (i) receives said first orientation change signal from said remote terminal, (ii) generates a control signal based on said orientation detected in said orientation sensor and a plurality of categories and lookup table associated with said first set of display devices and said second set of display devices, and (iii) transmits said control signal to said at least one salve display device positioned in at least one of said first panel and said second panel, and to the remote terminal for future processing
2. The system as claimed in claim 1, wherein said control unit receives said control signal and changes said content orientation of said first set of display devices and said second set of display devices based on said control signal.
3. The system as claimed in claim 1, wherein said control unit stores (i) at least one of said plurality of categories associated with each of said first set of display devices and said second set of display devices and (ii) a lookup table which comprises a different combinations of said plurality of categories and a plurality of view orientations for each of aid first set of display devices and said second set of display devices.
4. The system as claimed in claim 1, wherein each of said first set of display devices and said second set of display devices comprises a plurality of control buttons which allows a user to

transmit said third orientation change signal to said remote terminal for changing said content orientation of
(a) said second set of display devices from at least one of said first set of display devices and (b) said first set of display devices from at least one of said second set of display devices.
5. The system as claimed in claim 5, wherein said plurality of control buttons provided in
said each of said first set of display devices and said second set of display devices is allow user
to
transmit a second orientation change signal to said master display device positioned in at least one of (i) said first panel from said first set of display devices and (ii) said second panel from said second set of display devices for changing said content orientation of devices installed in the same panel.
6. A method for changing content orientation of a first set of display devices (304A1-n)
positioned in a first panel (302A) and a second set of display devices (304B1-n) positioned in a
second panel (304A), wherein each of said first set of display devices and said second set of
display devices comprises a master display device (304A1, 304B1) and at least one slave
display device (304A2-n, 304B2-n), method system comprising the steps of.
receiving (702), at a said master display device, a first orientation change signal from a remote terminal (308);
obtaining (704), from an orientation sensor (306A-B), an orientation of said master display device;
generating (706), at a control unit of said master display device, a control signal based on said orientation and a look up table stored in said control unit; and
transmitting (708) said control signal to said at least one of slave display devices from said master display device.
7. The method as claimed in claim 6, comprising:
receiving (710), at said master display device, a second orientation change signal from said at least one slave display devices;
generating (712), at said control unit of said master display device, said control signal based on said orientation and a look up table stored in said control unit; and

transmitting (714) said control signal to said at least one of slave display devices and remote terminal from said master display device.
8. The method as claimed in claim 6, comprising:
receiving (716), at said remote terminal, a third orientation change signal from at least one of first set of display devices and said second set of display devices;
transmitting (718), from said remote terminal, said first orientation change signal to said master display device based on said third orientation change signal;
generating (720), at said control unit of said master display device, said control signal based on said orientation and said look up table stored in said control unit; or remote terminal can also send orientation message based on saved control signals; and
transmitting (722) said control signal to said at least one of slave display devices from said master display device.