DESC:TECHNICAL FIELD

[001] The present subject matter described herein, in general, relates to a communication system or specifically master slave communication system,and more particularly,to a communication system connecting multiple device or microcontroller in a daisy chain arrangement.

BACKGROUND

[002] Several communication techniques are available for enabling communication between a processor or a master device and a plurality of serial devices or slave devices coupled to the processor. Conventionally, the master device communicates with one or more slave devices in particular communication architecture. One of such communication architecture is daisy chain communication architecture wherein the processor or the master device communicates with multiple slave devices connected in series one after another. The daisy chain is an interconnection of multiple computer devices, peripherals, or network nodes in series, one after another, so as to perform communication between many devices by linking a transmit output of one device to a receive output of a subsequent device.

[003] The master-slave communication system enables the master device to control one or more slave devices. Each slave device has a communication link for transmitting and/or receiving signals between it and the master device.As illustrated in figure 1, the conventional daisy chain includes single master device is configured to control and/or communicate with n number slave devices connected in sequence such that the data output of the master device is connected to the data input of the first slave device using a connection means; the data output of the first slave is connected to the data input of the second slave using the connection means; and simultaneously the data output of the second slave is connected to the data input of the third slave using the connection means and so on. However, such a master-slave communication in a daisy chain arrangement, the bandwidth of the master device is reduced and thus the master device may fail to process other critical tasks.

[004] Thus, in view the hitherto drawbacks of the master slave communication technique, there exists a dire need to provide a suitable solution that enables faster communication of data between the master and slave devices connected in the daisy chain arrangement and enhance theavailability of the master device so as to perform other critical tasks in a communication network.

SUMMARY OF THE INVENTION

[005] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[006] The main object of the present invention is to provide an improved master-slave communication technique in a daisy chain architecture so to prevent redundant usage of the master device in the communication network.

[007] Another object of the present invention is to provide an improved master-slave communication technique in thedaisy chain architecture by employing at least two master devices to communicate with plurality of slave devices connected serially to one another. Specifically, the present invention enables daisy chain communication in embedded system i.e. communication within embedded device using Ethernet backbone. Further, the present invention enables main master can collect data of any slave from second master, also main master can collect critical data from any slave directly. Furthermore, the present invention is focused to increase bandwidth of main master by reducing communication frequency in order to perform most critical activities.

[008] Yet another object of the present invention is to provide an improved master-slave communication technique in a daisy chain architecture so as to augment the availability of a main-master device to perform other critical tasks in a communication network.

[009] In one implementation, the present invention provides a multi-master communication system wherein the at least two master devices is configured to communicate with plurality of slave devices connected serially to each other in a daisy chain architecture. The two master devices in the communication network are a main master device and a second master device.

[0010] In one implementation, the present invention provides a multi-master communication system whereinat least one of the slave devices is used as a master deviceor second master device for communication with plurality of slave devices connected serially to one another and the master device or second master device is a used as a slave device for the main master device in the communication network.

[0011] In one implementation, the present invention provides a multi-master communication system wherein the main master deviceis configured to communicate with second master device only and thus will not communicate with every slave device in the communication network. The second master device is configured to collect data from plurality of slave devices connected serially to one another in a daisy chain arrangement.

[0012] In one implementation, the present invention provides a multi-master communication system wherein in an event when the main master device wants data from plurality of slave device, the master device is configured to send a request to the second master device. The second master device is configured to return a response to the main master device by receiving the request from the main master device and thereby transmitting a cumulative data of plurality of slave devices coupled to the second master device.

[0013] Accordingly, in one implementation, the present invention provides a daisy chain system having an interconnection of plurality of devices in series. The daisy chain system comprises at least two master devices, a first master device and a second master device, wherein the first master device is configured to communicate with the second master device; andat least one slave device configured to communicate with the second master device, wherein the second master device collect data from all the slave devices, and acts as a slave device for the first master device.

[0014] As compared to the prior art techniques, a daisy-chain using dual port Ethernet within embedded device, which consist of multiple processors (multiple cards) is disclosed. Further, in order to achieve the communication, the software and frames of intercommunication protocol are provided.

[0015] In one implementation, as compared to the prior art techniques, the present invention i.e., the device includes at least five different cards, which perform different functionalities.Among these cards, one is master card and others are slave cards connected in daisy-chain fashion using Ethernet backbone communication. Ethernet switch used on all cards include two ports. For example, the port 2 of a master card is connected to the port 1 of the slave 1, the port 2 of the slave 1 is connected to the port 1 of the slave 2 and so on.

[0016] In one implementation, to reduce communication frequency of master card with other cards, a second master is provided. First, the main master transmits synchronization command, and on reception of the synchronization command the second master collects data from other slave cards. Further, if second master fails to response to main master (except physical disconnection), then main master can collect data or send commands directly from/to other slaves.

[0017] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0018] Figure 1 illustratesexisting daisy chain architecture, in accordance with an embodiment of the present subject matter.

[0019] Figure 2 illustrates multi-master daisy chain architecture, in accordance with an embodiment of the present subject matter.

[0020] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0021] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0022] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0023] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0024] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0025] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0026] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0027] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0028] Referring now to figure 1, existing daisy chain architecture is illustrated. In one implementation a single master device is configured to control and/or communicate with n number slave devices connected in sequence such that the data output of the master device is connected to the data input of the first slave device using a connection means; the data output of the first slave is connected to the data input of the second slave using the connection means; and simultaneously the data output of the second slave is connected to the data input of the third slave using the connection means and so on.

[0029] Referring now to figure 2, multi-master daisy chain architecture is illustrated.

[0030] In one implementation, multi-master daisy chain architecture comprises at least two master devices and a plurality of slave devices. The master device is a main device and a second master device wherein the main master device is configured to communication with the second master device and the second master device is configured to communicate with plurality of slave device. The second master device communicates with slave devices and transmits a cumulative data to the main master device; also second master is slave for main master. This mode of communication reduces communication time and frequency of main master device and its bandwidth get improved to process other task.

[0031] In one implementation, the multi-master daisy chain architecture, one of the slave devices is used as master (second master) for all other slaves and this second master device is a slave device for main master device. Herein the main master device communicates with the second master device only. The main master is not communicating with every slave device in the communication network. The second master collects data from all the slave devices and when the main master deviceis triggered to receive data from slave devices, the main master device sends a request to the second master device. Then in response to that request from the main master device, the second master device is configured to cumulate data of all slave devices including second master data and thereby transmits the cumulative data to the main master. By using this mechanism main master device communication frequency is reduced and thereby the main master device bandwidth increases to process other critical tasks.

[0032] In one implementation, in conventionaldaisy chain architecture, 5 slave devices are connected to a master device, and the master device is communicating with one slave device within a time period of 2 milliseconds interval and thus the master device takes 10 milliseconds to communicate with 5 slave devices.However when the conventional communication system is modified with two master architecture enabling slave 1 to act as a second master device for the remaining 4 slave devices and the second master device is configured to collect data on 2 milliseconds interval, thus within a time period of 8 milliseconds the second master deviceis ready with data of all slaves. Then main master deviceis configured receive data of all slaves from the second master device after a time period of 10 milliseconds. Therefore, the main master device is made free for 10 milliseconds so as to do other tasks in two master daisy slave architecture overcoming the drawback of the conventional daisy chain architecture wherein a single master device is configured to communicate with the slave device on every 2 milliseconds.

[0033] Some of the important features of the present invention, considered to be noteworthy are mentioned below:
1. With multi master architecture the communication load to other node available in the network is distributed.
2. With multi master architecture, communication time and frequency of main master device is reduced.
3. With multi master architecture, the bandwidth of main master deviceis improved so as to process other critical tasks in the communication network.
,CLAIMS:1. A daisy chain system having an interconnection of plurality of devices in series, the daisy chain system comprising:
at least two master devices, a first master device and a second master device, wherein the first master device is configured to communicate with the second master device; and
at least one slave device configured to communicate with the second master device, wherein the second master device collect data from all the slave devices, and acts as a slave device for the first master device.

2. The daisy chain system as claimed in claim 1, wherein the second master device is configured to send the data collected to the first master device on receipt of at least one request from the first master device, and thereby act as the slave device for the first master device.

3. The daisy chain system as claimed in claim 1, whereinthe master devices and the slave device, respectively,comprises at least one dual port Ethernetembedded.

4. The daisy chain system as claimed in claim 3, wherein themaster devices and the slave device,respectively, comprises at least one processor or card.

5. The daisy chain system as claimed in claim 3, wherein the master devices and the slave device, respectively, comprises Ethernet switch having at least two ports.

6. The daisy chain system as claimed in claim 1, wherein the communication is achieved using an Ethernet.

7. The daisy chain system as claimed in claim 1, wherein the master devices and the slave device, respectively, comprises more than two processors or cards,and a dual port Ethernet embedded equal to the number of processors or card.

8. The daisy chain system as claimed in claim 1, wherein the master devices comprises at least one processor or card, and the slave device comprises one or more processor or card, and a dual port Ethernet embedded, the dual port Ethernet embedded is equal to the number of processor or card.