Patent Publication Number: US-2022230594-A1

Title: Method for operating electronic device and electronic device for supporting the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation application of prior application Ser. No. 16/865,971, filed on May 4, 2020, which is a continuation application of prior application Ser. No. 15/336,271, filed on Oct. 27, 2016, which has issued as U.S. Pat. No. 10,643,545 on May 5, 2020 and is based on and claims priority under 35 U.S.C. § 119(a) of a Korean patent application number 10-2015-0149697, filed on Oct. 27, 2015, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a method for operating an electronic device which outputs a screen via a display driving circuit and the electronic device for supporting the same. 
     BACKGROUND 
     An electronic device such as a smartphone, a tablet personal computer (PC), or a smart watch may output a variety of content such as videos, images, and text on its display panel. The display panel may be driven via a display driving circuit of the electronic device. The display driving circuit may receive image data from a processor in the electronic device and may output the received image data on the display panel. 
     The display driving circuit according to the related art only performs a function of receiving image data from the processor and outputting the received image data on the display panel. The display driving circuit according to the related art does not generate a separate image or use signals received from peripheral circuits. 
     Also, an application processor (AP) has to be repeatedly driven in order for the display driving circuit according the related art to output a touch-related image or output a second hand of a digital watch or an analog watch, resulting in increased power consumption. 
     The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure. 
     SUMMARY 
     Aspects of the present disclosure are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present disclosure is to provide a method for operating an electronic device to reduce the number of times of driving an application processor (AP) by generating and outputting an image added to a main image at its display driving circuit and the electronic device for supporting the same. 
     Another aspect of the present disclosure is to provide a method for operating an electronic device to perform calculation of a second hand using its display driving circuit and to output an analog watch or a digital watch and the electronic device for supporting the same. 
     Another aspect of the present disclosure is to provide a method for operating an electronic device to quickly output a zoomed-in image for a portion a user wants using its display driving circuit and the electronic device for supporting the same. 
     In accordance with an aspect of the present disclosure, a method of operating an electronic device is provided. The method includes receiving, by a display driving circuit of the electronic device, main image data over a first channel from a first processor or a second processor of the electronic device, outputting, by the display driving circuit, a main image on a display panel of the electronic device based on the main image data, generating, by the display driving circuit, an additional image different from the main image, merging, by the display driving circuit, the main image with the additional image, and outputting, by the display driving circuit, the merged image on the display panel. 
     In accordance with an aspect of the present disclosure, an electronic device is provided. The electronic device includes a first processor, a second processor, which is independent of the first processor, configured to perform calculation for a function, a display panel, and a display driving circuit configured to receive main image data over a first channel from the first processor or the second processor, output a main image based on the main image data, generate an additional image different from the main image, merge the main image with the additional image, and output the merged image on the display panel. 
     Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a block diagram illustrating a configuration of an electronic device according to an embodiment of the present disclosure; 
         FIG. 2  is a block diagram illustrating a detailed configuration of a display driving circuit according to an embodiment of the present disclosure; 
         FIG. 3  is a flowchart illustrating a method for operating an electronic device according to an embodiment of the present disclosure; 
         FIG. 4  is a flowchart illustrating a method for operating an electronic device using a plurality of processors according to an embodiment of the present disclosure; 
         FIG. 5A  is a screen illustrating a method for operating an electronic device according to an embodiment of the present disclosure; 
         FIG. 5B  is a drawing illustrating a method for showing an additional image according to an embodiment of the present disclosure; 
         FIG. 5C  is a screen illustrating a process of outputting a cursor image as an additional image according to an embodiment of the present disclosure; 
         FIG. 6A  is a screen illustrating a process of outputting a changed additional image according to an embodiment of the present disclosure; 
         FIG. 6B  is a screen illustrating a change of an additional image according to an embodiment of the present disclosure; 
         FIG. 6C  is a screen illustrating a process of outputting an additional image on a specified range of a screen according to an embodiment of the present disclosure; 
         FIG. 7  is a flowchart illustrating a method for extracting a partial image from a main image configured with a plurality of images and outputting the extracted image as an additional image according to an embodiment of the present disclosure; 
         FIG. 8  is a screen illustrating a process of extracting and outputting a partial image from a combination image configured with a plurality of images according to an embodiment of the present disclosure; 
         FIGS. 9A and 9B  are block diagrams illustrating a configuration of a display driving circuit which performs time calculation according to various embodiments of the present disclosure; 
         FIG. 10  is a block diagram illustrating a configuration of an electronic device for configuring a watch of a second hand according to an embodiment of the present disclosure; 
         FIG. 11  is a drawing illustrating an implementation example of a digital watch of a second hand via a digital driving circuit according to an embodiment of the present disclosure; 
         FIG. 12  is a block diagram illustrating a process of outputting a digital watch in a sub-display driving circuit according to an embodiment of the present disclosure; 
         FIG. 13  is a drawing illustrating an implementation example of an analog watch according to an embodiment of the present disclosure; 
         FIG. 14  is a block diagram illustrating a detailed configuration of a sub-display driving circuit for implementing an analog watch according to an embodiment of the present disclosure; 
         FIG. 15  is a drawing illustrating a second hand drawing method using a Bresenham algorithm according to an embodiment of the present disclosure; 
         FIG. 16  is a block diagram illustrating a configuration of an electronic device in a network environment according to an embodiment of the present disclosure; and 
         FIG. 17  is a block diagram illustrating a configuration of an electronic device according to an embodiment 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 
     The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness. 
     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 present disclosure. Accordingly, it should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustration purpose only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents. 
     It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces. 
     In the disclosure disclosed herein, the expressions “have”, “may have”, “include” and “comprise”, or “may include” and “may comprise” used herein indicate existence of corresponding features (for example, elements such as numeric values, functions, operations, or components) but do not exclude presence of additional features. 
     In the disclosure disclosed herein, the expressions “A or B”, “at least one of A or/and B”, or “one or more of A or/and B”, and the like used herein may include any and all combinations of one or more of the associated listed items. For example, the term “A or B”, “at least one of A and B”, or “at least one of A or B” may refer to all of the case ( 1 ) where at least one A is included, the case ( 2 ) where at least one B is included, or the case ( 3 ) where both of at least one A and at least one B are included. 
     The terms, such as “first”, “second”, and the like used herein may refer to various elements of various embodiments of the present disclosure, but do not limit the elements. For example, such terms are used only to distinguish an element from another element and do not limit the order and/or priority of the elements. For example, a first user device and a second user device may represent different user devices irrespective of sequence or importance. For example, without departing the scope of the present disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. 
     It will be understood that when an element (for example, a first element) is referred to as being “(operatively or communicatively) coupled with/to” or “connected to” another element (for example, a second element), it can be directly coupled with/to or connected to the other element or an intervening element (for example, a third element) may be present. In contrast, when an element (for example, a first element) is referred to as being “directly coupled with/to” or “directly connected to” another element (for example, a second element), it should be understood that there are no intervening element (for example, a third element). 
     According to the situation, the expression “configured to” used herein may be used as, for example, the expression “suitable for”, “having the capacity to”, “designed to”, “adapted to”, “made to”, or “capable of”. The term “configured to (or set to)” must not mean only “specifically designed to” in hardware. Instead, the expression “a device configured to” may mean that the device is “capable of” operating together with another device or other components. Central processing unit (CPU), for example, a “processor configured to (or set to) perform A, B, and C” may mean a dedicated processor (for example, an embedded processor) for performing a corresponding operation or a generic-purpose processor (for example, a CPU or an application processor (AP)) which may perform corresponding operations by executing one or more software programs which are stored in a memory device. 
     Unless otherwise defined herein, all the terms used herein, which include technical or scientific terms, may have the same meaning that is generally understood by a person skilled in the art. It will be further understood that terms, which are defined in a dictionary and commonly used, should also be interpreted as is customary in the relevant related art and not in an idealized or overly formal detect unless expressly so defined herein in various embodiments of the present disclosure. In some cases, even if terms are terms which are defined in the specification, they may not be interpreted to exclude embodiments of the present disclosure. 
     An electronic device according to various embodiments of the present disclosure may include at least one of smartphones, tablet personal computers (PCs), mobile phones, video telephones, electronic book readers, desktop PCs, laptop PCs, netbook computers, workstations, servers, personal digital assistants (PDAs), portable multimedia players (PMPs), Moving Picture Experts Group phase 1 or phase 2 (MPEG-1 or MPEG-2) audio layer 3 (MP3) players, mobile medical devices, cameras, and wearable devices. According to various embodiments of the present disclosure, the wearable devices may include accessories (for example, watches, rings, bracelets, ankle bracelets, glasses, contact lenses, or head-mounted devices (HMDs)), cloth-integrated types (for example, electronic clothes), body-attached types (for example, skin pads or tattoos), or implantable types (for example, implantable circuits). 
     In some embodiments of the present disclosure, the electronic device may be one of home appliances. The home appliances may include, for example, at least one of a digital versatile disc (DVD) player, an audio, a refrigerator, an air conditioner, a cleaner, an oven, a microwave oven, a washing machine, an air cleaner, a set-top box, a home automation control panel, a security control panel, a television (TV) box (for example, Samsung HomeSync™, Apple TV™, or Google TV™), a game console (for example, Xbox™ or PlayStation™), an electronic dictionary, an electronic key, a camcorder, or an electronic panel. 
     In an embodiment of the present disclosure, the electronic device may include at least one of various medical devices (for example, various portable medical measurement devices (a blood glucose meter, a heart rate measuring device, a blood pressure measuring device, and a body temperature measuring device), a magnetic resonance angiography (MRA), a magnetic resonance imaging (MRI) device, a computed tomography (CT) device, a photographing device, and an ultrasonic device), a navigation system, a global navigation satellite system (GNSS), an event data recorder (EDR), a flight data recorder (FDR), a vehicular infotainment device, electronic devices for vessels (for example, a navigation device for vessels and a gyro compass), avionics, a security device, a vehicular head unit, an industrial or home robot, an automatic teller&#39;s machine (ATM) of a financial company, a point of sales (POS) of a store, or an internet of things (for example, a bulb, various sensors, an electricity or gas meter, a spring cooler device, a fire alarm device, a thermostat, an electric pole, a toaster, a sporting apparatus, a hot water tank, a heater, and a boiler). 
     According to some embodiments of the present disclosure, the electronic device may include at least one of a furniture or a part of a building/structure, an electronic board, an electronic signature receiving device, a projector, or various measurement devices (for example, a water service, electricity, gas, or electric wave measuring device). In various embodiments of the present disclosure, the electronic device may be one or a combination of the aforementioned devices. The electronic device according to some embodiments of the present disclosure may be a flexible electronic device. Further, the electronic device according to an embodiment of the present disclosure is not limited to the aforementioned devices, but may include new electronic devices produced due to the development of technologies. 
     Hereinafter, electronic devices according to an embodiment of the present disclosure will be described with reference to the accompanying drawings. The term “user” used herein may refer to a person who uses an electronic device or may refer to a device (for example, an artificial electronic device) that uses an electronic device. 
       FIG. 1  is a block diagram illustrating a configuration of an electronic device according to an embodiment of the present disclosure. 
     Referring to  FIG. 1 , an electronic device  101  may be a device such as a smartphone and a tablet PC or a wearable device such as a smart watch and a smart band, each of which has a screen output function. The electronic device  101  may include a first processor  110 , a second processor  120 , a display driving circuit  130 , and a display panel  150 . 
     The first processor  110  may execute, for example, calculation or data processing about control and/or communication of at least another component of the electronic device  101 . In various embodiments, the first processor  110  may be a CPU or an AP. 
     The processor  110  may send image data to be output on the display panel  150  to the display driving circuit  130  over a first channel  111 . An image (hereinafter referred to as “main image”) output through the image data may be output on a frame-by-frame basis on the display panel  150 . For example, if the display panel  150  outputs a screen at a rate of 60 frames per second, the first processor  110  may send image data corresponding to one frame to the display driving circuit  130  60 times per second. The display driving unit  130  may generate a main image based on each image data and may output the generated main image on the display panel  150 . 
     According to various embodiments, if a currently output first frame is the same as a second frame to be output subsequent to the first frame, the first processor  110  may not send separate image data to the display driving circuit  130 . In this case, the display driving circuit  130  may continue outputting a still image stored in its graphic random access memory (RAM). 
     According to various embodiments, the first processor  110  may provide data, image processing of which is performed using a specified algorithm, to the display driving circuit  130 . For example, the first processor  110  may compress a screen frame data using the specified algorithm and may provide the compressed data to the display driving circuit  130  at a fast speed. The display driving circuit  130  may decompress a compressed image and may output the decompressed image on the display panel  150 . 
     In various embodiments, the first processor  110  may send a control signal to the display driving circuit  130  over a second channel  112 . The control signal may be a signal of a text format, distinguished from the image data. The display driving circuit  130  may generate an image (hereinafter referred to as “additional image”) to be output together with the main image received over the first channel  111  based on the control signal. 
     The second processor  120  may be a separate processor independent of the first processor  110 . The second processor  120  may be a processor which performs calculation necessary for executing a specified function to be different from the first processor  110 . The second processor  120  may send image data or a control signal to the display driving circuit  130  to be similar to the first processor  110 . The second processor  120  may send image data to the display driving circuit  130  over the first channel  111  and may send a control signal to the display driving circuit  130  over the second channel  112 . The image data may be data for forming a main image output on the display panel  150 . The control signal may be a signal for generating an additional image output by being added to the main image. 
     In various embodiments, the second processor  120  may be a module or chip such as a communication processor (CP), a touch control circuit, a touch pen control circuit, or a sensor hub. 
     The CP may perform a function of managing a data link in communication between the electronic device  101  and other electronic devices connected with the electronic device  101  by a network and converting a communication protocol. The CP may perform calculation for a communication service such as a voice call service, a video call service, a text message service (e.g., a short message service (SMS), a multimedia message service (MMS), and the like), or a packet data service. 
     The touch control circuit may control a touch panel correspondingly combined with the display panel  150 . The touch control circuit may process touch gesture information input from the touch panel or may control an operation of the touch panel. The touch controller circuit may include a driver circuit, a sensor circuit, a control logic, an oscillator, a delay table, an analog-digital converter, a micro controller unit (MCU), and the like. 
     The sensor hub may include an MCU and may control at least one sensor. The sensor hub may collect sensing information detected by various sensors and may control an operation of each of the sensors. The sensors may include a temperature/humidity sensor, a biometric sensor, an atmospheric pressure sensor, a gyro sensor, and the like. 
     According to various embodiments, the second processor  120  may connect with the first processor  110  over a separate channel  113  (e.g., an inter integrated circuit (I2C)). In various embodiments, the second processor  120  may provide a control signal provided to the display driving circuit  130  to the first processor  110 . For example, if the second processor  120  is a touch control circuit and if the first processor  110  is an AP, the touch control circuit may provide a coordinate of a point where a touch input of a user of the electronic device  101  occurs to both of the display driving circuit  130  and the AP. The first processor  110  may perform an operation associated with the touch input to change a main image. The display driving circuit  130  may generate an additional image on the point where the touch input occurs and may output the generated additional image together with the main image. The display driving circuit  130  may be a driving circuit for outputting an image on the display panel  150 . The display driving circuit  130  may receive image data from the first processor  110  or the second processor  120  and may output an image through image conversion. 
     According to various embodiments, the display driving circuit  130  may include a sub-display driving circuit  140 . The sub-display driving circuit  140  may generate an additional image to be output together with the main image, based on the control signal provided from the first processor  110  or the second processor  120 . The additional image may be output on a partial region or a specified region of the display panel  150 . Information about generating and outputting the additional image via the sub-display driving circuit  140  may be provided with reference to  FIGS. 2, 3, 4, 5A to 5C, 6A to 6C, 7, 8, 9A, 9B, 10, 11, 12, 13, 14, 15, 16, and 17 . 
     The display panel  150  may output a screen such as an image and text. The display panel  150  may be, for example, a liquid-crystal display (LCD) or an active-matrix organic light-emitting diode (AM-OLED). The display panel  150  may be implemented to be flexible, transparent, or wearable. The display panel  150  may be included in, for example, a cover of a case electrically combined with the electronic device  101 . 
     The display panel  150  may receive and output a signal about the main image or the additional image. The display panel  150  may be implemented in the form of intersecting a plurality of data lines and a plurality of gate lines. At least one pixel is arranged in points where the data lines and the gate lines are intersected. If the display panel  150  corresponds to an OLED panel, it may include one or more switching elements (e.g., field effect transistors (FETs)) and one OLED. Each pixel may receive an image signal and the like at timing from the display driving circuit  130  and may generate light. 
     According to various embodiments, the first channel  111  may send image data for outputting a main image to the display driving circuit  130 , and the second channel may send a control signal for generating an additional image to the display driving circuit  130 . The image data may have a relatively larger data capacity than that of the control signal. The first channel  111  which transmits the image data may be a channel which secures a data transmission rate which is faster than the second channel  112  which transmits the control signal. For example, the first channel  111  may be a high speed serial interface (HiSSI), and the second channel  112  may be a low speed serial interface (LoSSI). 
       FIG. 2  is a block diagram illustrating a detailed configuration of a display driving circuit according to an embodiment of the present disclosure. 
     Referring to  FIG. 2 , a display driving circuit  130  may include an interface (I/F) module  210 , a graphic RAM  220 , an image processing module  230 , a sub-display driving circuit  140 , a multiplexer  240 , a timing controller  250 , a source driver  260 , and a gate driver  270 . 
     The I/F module  210  may receive image data or a control signal from a processor  110  or a second processor  120  of  FIG. 1 . The I/F module  210  may include an HiSSI  211  and an LoSSI  212 . The HiSSI  211  may establish a first channel  111  which may receive image data for a main image, and the LoSSI  212  may establish a second channel  112  which may receive control information for generating an additional image. In various embodiments, the I/F module  210  may further include an I/F controller (not shown) for controlling the HiSSI  211  and the LoSSI  212 . 
     The HiSSI  211  (e.g., a mobile industry processor interface (MIPI)) may receive image data from the processor  110  or the second processor  120  and may provide the image data to the graphic RAM  220 . The HiSSI  211  may quickly transmit image data having relatively more amounts of data than that of a control signal. 
     The LoSSL  212  (e.g., a serial peripheral interface (SPI) or an I2C) may receive a control signal from the first processor  110  or the second processor  120  and may provide the control signal to the sub-display driving circuit  140 . 
     The graphic RAM  220  may store the image data provided from the first processor  110  or the second processor  120 . The graphic RAM  220  may include a memory space corresponding to resolution and/or the number of color gradations of a display panel  150 . The graphic RAM  220  may be referred to as a frame buffer or a line buffer. 
     The image processing module  230  may convert the image data stored in the graphic RAM  220  into an image. The image data stored in the graphic RAM  220  may be in the form of data in which image processing is performed using a specified algorithm. The image data may be compressed using the specified algorithm for fast transmission, and the compressed image data may be sent to the first channel  111 . The image processing module  230  may decompress a compressed image and may output the decompressed image on the display panel  150 . In various embodiments, the image processing module  230  may improve image quality of image data. Although not illustrated, the image processing module  230  may include a pixel data processing circuit, a pre-processing circuit, a gating circuit, and the like. 
     The sub-display driving circuit  140  may receive the control signal from the LoSSI  212 . The sub-display driving circuit  140  may generate an additional image to be output together with a main image based on the control signal. For one example, the additional image may be a simple graphic symbol, such as a circle or an icon, output on a partial region or a specified region of the display panel  150 . For another example, the additional image may be numbers (e.g., 00 second to 59 seconds) of a second hand of a digital watch or a second hand of an analog watch. Information about generating the additional image via the sub-display driving circuit  140  will be provided with reference to  FIGS. 3, 4, 5A to 5C, 6A to 6C, 7, 8, 9A, 9B, 10, 11, 12, 13, 14, 15, 16, and 17 . 
     The multiplexer  240  may merge a signal for the main image output from the image processing module  230  with a signal for the additional image output from the sub-display driving circuit  140  and may provide the merged signal to the timing controller  250 . 
     The timing controller  250  may generate a data control signal for controlling operation timing of the source driver  260  and a gate control signal for controlling operation timing of the gate driver  270  based on the signal merged by the multiplexer  240 . 
     The source driver  260  and the gate driver  270  may generate signals respectively provided to a scan line and a data line of the display panel  150 , based on the source control signal and the gate control signal received from the timing controller  250 . 
       FIG. 3  is a flowchart illustrating a method for operating an electronic device according to an embodiment of the present disclosure. 
     Referring to  FIG. 3 , in operation  310 , a display driving circuit  130  of  FIG. 1  may receive image data (hereinafter referred to as “main image data”) over a first channel  111  of  FIG. 1  from a first processor  110  or a second processor  120  of  FIG. 1 . 
     For example, the first processor  110  or the second processor  120  may provide various images (e.g., an album view screen, a video output screen, a memo note, a schedule screen, a keyboard input screen, and the like) according to execution of an application to the display driving circuit  130 . In various embodiments, the main image data may be a sleep screen, an idle screen, a home screen, a lock screen, or the like. 
     In operation  320 , the display driving circuit  130  may receive a control signal over a second channel  112  of  FIG. 2  from the first processor  110  or the second processor  120 . The control signal may be a signal of a text format, distinguished from the main image data received over the first channel  111 . 
     According to various embodiments, the control signal may be coordinate information on a screen by a body (e.g., a finger) or a touch pen of a user of the electronic device  101 , arranged to be adjacent to the screen. For example, if the second processor  120  is a touch control circuit and if the body (e.g., the finger) of the user is arranged to be adjacent to the screen, the touch control circuit may send a coordinate value of the closest location to the body of the user or a capacitance change value on the coordinate to the display driving circuit  130  over the second channel  112 . 
     In operation  330 , the display driving circuit  130  may output an image on a display panel  150  of  FIG. 1  based on the main image data and the control signal. The display driving circuit  130  may generate an additional image based on the control signal. The display driving circuit  130  may merge the generated additional image with a main image based on the main image data and may output the merged image. 
     For one example, if receiving the coordinate value of the closest location to the body of the user or the capacitance change value on the coordinate from the touch control circuit, the display driving circuit  130  may generate a shadow image (e.g., a circle or oval) of lowering luminance of pixels which belongs to a specified range on the coordinate value as an additional image. The shadow image may be directly displayed via the display driving circuit  130 . Information about a process of receiving the control signal from the touch control circuit or the touch pen control circuit and generating the additional image will be provided with reference to  FIGS. 5A to 5C and 6A to 6C . 
     For another example, the display driving circuit  130  may receive a control signal associated with driving a digital watch or an analog watch from the first processor  110  or the second processor  120 . The display driving circuit  130  may display hour and minute information of the digital watch or the analog watch through a main image, may generate an additional image of displaying second information generated in the display driving circuit  130 , may merge the generated additional image with the main image, and may output the merged image. Information about a method of showing the digital watch or the analog watch in the display driving circuit  130  will be provided with reference to  FIGS. 10 to 15 . 
       FIG. 4  is a flowchart illustrating a method for operating an electronic device using a plurality of processors according to an embodiment of the present disclosure. 
     Referring to  FIG. 4 , in operation  410 , a display driving circuit  130  of  FIG. 1  may receive main image data over a first channel  111  of  FIG. 1  from a first processor  110  of  FIG. 1 . The display driving circuit  130  may output a main image through the main image data. For example, the main image data may be data about an execution screen of various applications, a home screen, an idle screen, a sleep screen, and the like. In various embodiments, the first processor  110  may be an AP. 
     In operation  420 , the display driving circuit  130  may receive a control signal over a second channel  112  of  FIG. 1  from a second processor  120  of  FIG. 1 . The control signal may be a signal of a text format, distinguished from the main image data received over the first channel  111 . In various embodiments, the second processor  120  may be a touch control circuit, a touch pen controller, or the like. 
     For example, the display driving circuit  130  may receive coordinate information of a point, where a body (e.g., a finger) of a user of an electronic device  101  of  FIG. 1  is adjacent to a screen, from the touch control circuit. The coordinate information may be transmitted over the second channel  112 . 
     In operation  430 , the display driving circuit  130  may generate an additional image according to the control signal. The control signal may be a message signal of a text format. The display driving circuit  130  may generate an additional image based on information (e.g., coordinate information) included in the control signal. 
     For one example, if receiving coordinate information from the touch control circuit, the sub-display driving circuit  140  may generate a shadow image on the coordinate. The shadow image may be generated by lowering a luminance value of pixels included within a specified range. 
     For another example, if receiving coordinate information of a location to which a touch pen is currently arranged to be adjacent from the touch pen control circuit, the display driving circuit  130  may generate a circular image on the coordinate. The sub-display driving circuit  140  may be configured to output an output color of pixels, which are within a specified distance from the coordinate, as a first color (e.g., black) and may be configured to output pixels adjacent to the pixels of the first color with a second color (e.g., gray). 
     In operation  440 , the display driving circuit  130  may merge the main image with the additional image and may output the merged image on a display panel  150  of  FIG. 1 . The display driving circuit  130  may merge the additional image based on the control signal provided from the second processor  120  with a main image through the main image data provided from the first processor  110  and may output the merged image. In various embodiments, the display driving circuit  130  may change settings of some pixels in settings of pixels which constructs the main image and may reflect the additional image in the main image. 
     According to various embodiments, the display driving circuit  130  may be configured to merge the additional image with the main image during a specified time or a specified frame. For example, if receiving a new main image to which an image corresponding to the additional image is added from the first processor  110 , the display driving circuit  130  may stop the operation of merging the additional image generated based on the control signal with the main image. 
       FIG. 5A  is a screen illustrating a method for operating an electronic device according to an embodiment of the present disclosure. 
     Referring to  FIG. 5A , a display driving circuit  130  of  FIG. 1  may add an additional image to a main image based on main image data provided via a first processor  110  (e.g., an AP) and may output the added image. The additional image (e.g., a shadow image and a circular or oval image) may be generated based on a control signal provided from a second processor  120  of  FIG. 1  (e.g., a touch control circuit and a touch pen control circuit). 
     In a screen  501 , an embodiment is exemplified as a shadow image  520  is output as an additional image if a body (e.g., a finger  510 ) of a user is arranged to be adjacent to a screen. 
     The display driving circuit  130  may output a main image  505  (e.g., a message input screen) on the screen  501  based on the main image data provided from the first processor  110 . The main image  505  may be output on a frame-by-frame basis. In various embodiments, if a currently output first frame is the same as a second frame to be output subsequent to the first frame, the first processor  110  may not send separate main image data to the display driving circuit  130 . In this case, the display driving circuit  130  may continue outputting a still image stored in its graphic RAM. The first processor  110  may provide new main image data to the display driving circuit  130  per specified time period or if there is a change to a currently outputted main image. 
     If the finger  510  of the user approaches the screen  501  while the main image is output, a change in capacitance may occur at a specific point of a touch panel adjacent to the finger  510 . The second processor  120  (e.g., a touch control circuit) may extract a coordinate value of the point. The second processor  120  may provide the extracted coordinate value to the display driving circuit  130  over a second channel  112  of  FIG. 1 . 
     The display driving circuit  130  may generate a shadow image  520  on the coordinate. The shadow image  520  may be generated by lowering a luminance value of pixels included in a specified range (e.g., a circle) or changing a hue value. For example, pixels included in the shadow image  520  may be set with a color (e.g., gray) which is darker than a peripheral region. 
     The display driving circuit  130  may merge the shadow image  520  with a currently outputted screen (e.g., a memo note, a text input window, a keyboard, and the like) of an application and may output the merged image. The user may verify where a point he or she will touch is, through an additional image. Since the first processor (e.g., the AP) is in a state where separate main image data is not transmitted to the display driving circuit  130  or in a sleep state while the additional image is output, power dissipation may be reduced. 
     According to various embodiments, the first processor  110  may receive a coordinate value of a point where a touch occurs from the touch control circuit which is the second processor  120 . The first processor  110  may generate a main image in which a shadow image is reflected on a coordinate and may provide the generated main image to the display driving circuit  130 . In this case, the display driving circuit  130  may stop outputting an additional image. The display driving circuit  130  may receive a signal for stopping outputting of the additional image over a second channel  112  from the first processor  110  (e.g., the AP) or the second processor  120  (e.g., the touch control circuit). 
     In a screen  502 , an embodiment is exemplified as a circular image  560  by approach of a touch pen  550  is output as an additional image. 
     The display driving circuit  130  may output a main image  540  (e.g., a memo note input screen) on the screen  502  based on main image data provided from the first processor  120 . The main image  540  may be output on a frame-by-frame basis. In various embodiments, the display driving circuit  130  may continue outputting a still image stored in the graphic RAM. 
     If the touch pen  560  approaches the screen  502  while the main image is output, a change in capacitance may occur at a specific point of a touch panel adjacent to the touch pen  560 . The second processor  120  (e.g., a touch pen control circuit (e.g., a Wacom integrated circuit (IC))) may extract a coordinate value of the point. The second processor  120  may provide the extracted coordinate value to the display driving circuit  130  over the second channel  112 . 
     The display driving circuit  130  may be configured to output pixels, which are within a specified distance from a coordinate, using a first color (e.g., a black color). In various embodiments, the display driving circuit  130  may be configured to naturally form the circular image  560  through anti-aliasing processing of outputting pixels adjacent to the pixels of the first color using a second color (e.g., a gray color). 
     In the screen  502 , an embodiment is exemplified as the circular image  560  is reflected in the main image  540  based on a location of the touch pen  550 . However, embodiments are not limited thereto. For example, the display driving circuit  130  may be configured to output a hovering menu of the touch pen  550  as an additional image. The display driving circuit  130  may draw a circular or hovering menu through calculation (e.g., integer calculation) of a simple form. 
       FIG. 5B  is a drawing illustrating a method for showing an additional image according to an embodiment of the present disclosure. In  FIG. 5B , an embodiment is exemplified as an additional image is a circular image. However, embodiments are not limited thereto. 
     Referring to  FIG. 5B , circular images  560   a  and  560   b  may be output via a display driving circuit  130  of  FIG. 1 . The display driving circuit  130  may merge the circular images  560   a  and  560   b  based on a control signal provided from a second processor  120  of  FIG. 1  with a main image generated based on main image data provided from a first processor  110  of  FIG. 1  and may output the merged image. 
     In the circular image  560   a , the display driving circuit  130  may receive a coordinate value about a specific point (e.g., a point where a touch input of a user occurs or a point adjacent to a touch pen) on a screen from the second processor  120 . 
     For example, if the coordinate value is (a, b), the display driving circuit  130  may draw the circular image  560   a  which has the coordinate value (a, b) as an origin point. The display driving circuit  130  may draw the circular image  560   a  according to Equation 1 below. 
       ( x−a ) 2 +( y−b ) 2 − r   =D   Equation 1
         (x, y): a location of a pixel included in the circular image  560   a      (a, b): a coordinate of an origin point   r: a radius of a circle   D: an anti-aliasing application distance       

     For example, the display driving circuit  130  may output pixels of a point where D is “0” (e.g., pixels which belong to a first range  561 ) using a first color (e.g., a black color). The first range  561  may include pixels of a point distant from the origin point (a, b) by the radius r. The display driving circuit  130  may output pixels of a point where D is greater than “0” (e.g., pixels which belong to a second range  562 ) using a second color (e.g., a gray color) which is brighter than the first color. Also, the display driving circuit  130  may output pixels of a point where D is less than “0” (e.g., pixels which belong to a third range  563 ) using the second color (e.g., the gray color). 
     The display driving circuit  130  may allow the circular image  560   a  to externally form a natural circle through anti-aliasing processing based on a D value. 
     According to various embodiments, the display driving circuit  130  may blend at least some of the pixels which belong to the first range  561  to the third range  563  with a main image (or a background image) and may output the blended image. For example, the display driving circuit  130  may blend the pixels which belong to the first range  561  with a background image at a specified ratio (e.g., the ratio of 50:50, the ratio of 25:75, and the like) and may output the blended image. In this case, the circular image  560   a  may have the similar color to that of the background image, and the sense of difference between the circular image  560   a  and the background image may be reduced. 
     According to various embodiments, the display driving circuit  130  may output the inside of the circular image  560   a  using the main image (or the background image). For example, the display driving circuit  130  may fill the inside of the circular image  560   a  with an image in which the background image is inverted. 
     According to various embodiments, although a control signal is not received from the second processor  120 , the display driving circuit  130  may output an additional image (e.g., the circular image  560   a ). For example, although a separate coordinate value is not received from the touch control circuit which is the second processor  120 , the display driving circuit  130  may output the circular image  560   a  on a coordinate (e.g., the center of a screen) set to a default. If a separate coordinate value is received through a control signal, the display driving circuit  130  may move the circular image  560   a  using the coordinate value. 
     In a circular image  560   b , the display driving circuit  130  may set different colors to ranges. For example, the display driving circuit  130  may output pixels which belong to a first range  565  of a point where D is “0”, using a first color (e.g., a black color). The display driving circuit  130  may output pixels of a point where D is greater than “0” (e.g., pixels which belong to a second range  566 ) using a second color (e.g., a gray color) which is brighter than the first color. The display driving circuit  130  may output pixels of a point where D is less than “0” (e.g., pixels which belong to a third range  567 ) using a third color (e.g., a blue color) which is different from the first color or the second color. 
     In  FIG. 5B , an embodiment is exemplified as it is classified into three intervals based on an anti-aliasing application distance D. However, embodiments are not limited thereto. For one example, the display driving circuit  130  may sequentially output the inside of a circle using a different color to provide various visual effects to the user. For another example, the display driving circuit  130  may display a circle based on an interval to output two or more circular images in the form of overlapping the two or more circular images. 
       FIG. 5C  is a screen illustrating a process of outputting a cursor image as an additional image according to an embodiment of the present disclosure. 
     Referring to  FIG. 5C , a display driving circuit  130  of  FIG. 1  may merge an additional image (e.g., a cursor image  570 ) with a main image based on main image data provided via a first processor  110  of  FIG. 1  (e.g., an AP) and may output the merged image on a screen  503 . The additional image (e.g., the cursor image  570 ) may be generated based on a control signal provided from a second processor  120  of  FIG. 1  (e.g., a touch control circuit and a touch pen control circuit). 
     In the screen  503 , an embodiment is exemplified as the cursor image  570  is output as the additional image by an application, such as a message application or a social network service (SNS) application, which may enter text. 
     The display driving circuit  130  may output a main image (e.g., a message application screen) on the screen  503  based on main image data provided from the first processor  110 . The main image may be output on a frame-by-frame basis. 
     If a user touches a text input window  574  while the main image (e.g., the message application screen) is output, the cursor image  570  may be generated on a first point (e.g., a left upper end of the text input window  574 ). The second processor  120  may provide a coordinate value of a coordinate the user touches to the display driving circuit  130  over a second channel  112  of  FIG. 1 . 
     If the coordinate value is included within a range of the text input window  574 , the display driving circuit  130  may generate the cursor image  570  on the first point. 
     According to various embodiments, the display driving circuit  130  may output the cursor image  570  to turn on/off the cursor image  570  at specified time intervals (e.g., 0.5 seconds). While outputting the cursor image  570  to be turned on/off, the display driving circuit  130  may not change the main image (e.g., the message application screen) provided via the first processor  110 . 
     According to various embodiments, the cursor image  570  may be output in the form of one of a form (e.g., a cursor image  570   a ) extended in a first direction (e.g., a longitudinal direction) or a form (e.g., a cursor image  570   b ) extended in a second direction (e.g., a transverse direction). The cursor image  570   a  may be shown relative to a start point  571  and may have a width  572  and a height  573 . The width  572  is smaller than the height  573 . The cursor image  570   a  may be turned on/off at a left or right side of entered text. 
     The cursor image  570   b  may be shown relative to a start point  575  and may have a width  576  and a height  577 . The width  576  is larger than the height  577 . The cursor image  570   b  may be turned on/off at a lower end of entered text. 
     According to various embodiments, if a start point (e.g., the start point  571  or  575 ) of the cursor image  570   a  or  570   b  is changed based on a text input of the user, the first processor  110  or the second processor  120  may provide a coordinate value changed to a control signal to the display driving circuit  130  over a second channel  112  of  FIG. 2 . The display driving circuit  130  may output the cursor image  570   a  or  570   b  relative to the changed start point. 
       FIG. 6A  is a screen illustrating a process of outputting a changed additional image according to an embodiment of the present disclosure. 
     Referring to  FIG. 6A , a display driving circuit  130  of  FIG. 1  may output a main image (e.g., a message input screen) on a screen  601  based on main image data provided from a first processor  110  of  FIG. 1 . The main image  605  may be output on a frame-by-frame basis. In various embodiments, if a currently output first frame is the same as a second frame to be output subsequent to the first frame, the first processor  110  may not send separate main image data to the display driving circuit  130 . The display driving circuit  130  may continue outputting a still image stored in its graphic RAM. 
     If a body (e.g., a finger  610 ) of a user approaches the screen  601  and is located within a first distance  610   a  (e.g., an initial location where capacitance of a touch panel is changed due to the approach of the finger  610 ), a shadow image  620   a  may be generated on the most adjacent point of the touch panel to the finger  610 . The method of generating the shadow image  620   a  may be the same or similar to an output method on a screen  501  of  FIG. 5A . 
     The shadow image  620   a  may be arranged on the closest point to the finger  610  (e.g., a point having the largest change in capacitance of the touch panel). For example, in case of the screen  601 , the shadow image  620   a  may be arranged around the periphery of a message input window. 
     If the finger  610  is moved to be gradually close to the screens  602  and  603  such that a distance between the finger  610  and the screens  602  and  603  is close within a second distance  610   b  and a third distance  610   c , a touch control circuit which is a second processor  120  of  FIG. 1  may continue providing a changed coordinate value (e.g., a coordinate value of a point having the largest change in capacitance) as a control signal to the display driving circuit  130 . A sub-display driving circuit  140  of  FIG. 1  may continue adding shadow images  620   b  and  602   c  on the coordinate value and may output the added shadow images  620   b  and  620   c.    
     Although the shadow images  620   a  to  620   c  are continuously changed in location due to the approach of the finger  610 , the first processor  110  may not change a main image and, if some cases, may maintain a sleep state. 
     In various embodiments, the touch control circuit may provide a control signal including a capacitance value to the display driving circuit  130 . The display driving circuit  130  may change a size of each of the shadow images  620   a  to  620   c  based on the capacitance value. For example, if the capacitance value is small, the display driving circuit  130  may generate an additional image of a relatively broad range like the shadow image  620   a . If the capacitance value is large, the display driving circuit  130  may generate an additional image of a relatively narrow range like the shadow image  620   c . The display driving circuit  130  may provide an effect of generating a real shadow when the finger  610  is moved to be closer to the screen  601 ,  602 , or  603  and displaying a location the user wants to touch to him or her. 
       FIG. 6B  is a screen illustrating a change of an additional image according to an embodiment of the present disclosure. In  FIG. 6B , an embodiment is exemplified as a touch image is output. However, embodiments are not limited thereto. 
     Referring to  FIG. 6B , a display driving circuit  130  of  FIG. 1  may be configured to change a color of an additional image (e.g., touch images  630   a  and  630   b ) on screens  604  and  605  as a body (e.g., a finger  610 ) of a user is distant from the screens  604  and  605 . 
     The display driving circuit  130  may receive and output a main image (e.g., a call keypad screen) from a first processor  110  of  FIG. 1 . If a touch input occurs from the user, the display driving circuit  130  may generate an additional image (e.g., the touch images  630   a  and  630   b ), may merge the generated additional image with the main image (e.g., the call keypad screen), and may output the merged image. 
     If a touch input of the user occurs (e.g., if the user touches the numeral  2  of a keypad), a second processor  120  of  FIG. 1  (e.g., a touch control circuit) may provide the coordinate value to the first processor  110  and the display driving circuit  130 . The first processor  110  may provide a main image, which displays the numeral  2  on the screens  604  and  605 , to the display driving circuit  130 . 
     The display driving circuit  130  may add the touch image  630   a  to the main image and may output the added image. The touch image  630   a  may be generated relative to a coordinate value received from the second processor  120 . For example, the touch image  630   a  may be a semi-transparent blue circular image. 
     If a specified time elapses after the touch input of the user, the display driving circuit  130  may output the touch image  630   b  to gradually lighten the touch image  630   a  in color (e.g., change the touch image  630   a  to the touch image  630   b ). A user may verify a point he or she touches recently during the specified time through the change of the touch image  630   a.    
     The display driving circuit  130  may output a touch image  640  to change the touch image  640  in size over time. In various embodiments, the display driving circuit  130  may output the touch image  640  to reduce the touch image  640  in size over time. 
     For example, if the user touches the numeral  5  of the keypad, the second processor  120  (e.g., the touch control circuit) may provide a coordinate value of a coordinate where a touch input occurs to the display driving circuit  130 . The display driving circuit  130  may output a touch image  640   a  having a specified size (or area) at a time when the coordinate value is received. 
     In various embodiments, the display driving circuit  130  may output the touch image  640   a  to gradually reduce the touch image  640   a  in size over a time period t when a specific frame (e.g., 5 frames, 10 frames, 20 frames, and the like) is changed. An initial size of the touch image  640   a  may be a size of an image  655  including 160 pixels. The touch image  640   a  may be gradually reduced in size over the time period t and may then be changed to a touch image  640   b . The touch image  640   b  may have a size of an image  651  including 10 pixels. For example, as shown in  FIG. 6B , the image  655  may be gradually changed to a reduced size image  651  by changing the image  655  having 160 pixels to an image  654  having 80 pixels, changing the image  654  having 80 pixels to an image  653  having 40 pixels, changing the image  653  having 40 pixels to an image  652  having 20 pixels, and changing the image  652  having 20 pixels to an image  651  having 10 pixels. 
     In various embodiments, the display driving circuit  130  may output the touch image  640  to increase the touch image  640  in size over time. For example, if the user moves part (e.g., a finger) of his or her body to be adjacent to the screen  606  to touch the numeral  5  of the keypad, the second processor  120  (e.g., the touch control circuit) may provide a coordinate value of a point where capacitance of a touch panel is changed to the display driving circuit  130 . For example, as shown in  FIG. 6B , the image  651  may be gradually changed to an enlarged size image  655  by changing the image  651  having 10 pixels to an image  652  having 20 pixels, changing the image  652  having 20 pixels to an image  653  having 40 pixels, changing the image  653  having 40 pixels to an image  654  having 80 pixels, and changing the image  654  having 80 pixels to an image  655  having 160 pixels. 
     The display driving circuit  130  may output touch image  640   b  at a time when the coordinate value is received. The display driving circuit  130  may output the touch image  640   b  to gradually increase the touch image  640   b  in size over the time period t when a specified frame (e.g., 5 frames, 10 frames, 20 frames, and the like) is changed. An initial size of the touch image  640   b  may be a size of the image  651  including the 10 pixels. The touch image  640   b  may be gradually increased in size over the time period t and may be changed to the touch image  640   a . The touch image  640   a  may have the size of the image  655  including 160 pixels. 
     In various embodiments, the display driving circuit  130  may output the touch image  640  to change the touch image  640  in color together with a size of the touch image  640  over time. For example, the display driving circuit  130  may set a first color for the touch image  640   a  and may set a second color which is darker than the first color for the touch image  640   b . The display driving circuit  130  may be configured to sequentially change the touch image  640  from the first color to the second color over time. 
       FIG. 6C  is a screen illustrating a process of outputting an additional image on a specified range of a screen according to an embodiment of the present disclosure. In  FIG. 6C , an embodiment is exemplified as a touch image is output on a keypad. However, embodiments are not limited thereto. 
     Referring to  FIG. 6C , a display driving circuit  130  of  FIG. 1  may output a touch image  670   a  of a specified range based on a coordinate value of a touch input. 
     If a main image is a text input screen, a user may push a button to be input (e.g., a button  670 ) and may enter text on screens  607  and  608 . A second processor  120  of  FIG. 1  (e.g., a touch control circuit) may provide a coordinate value of a point where a touch input of the user occurs to the display driving circuit  130 . 
     The display driving circuit  130  may output the touch image  670   a  on the button  670  including the coordinate value. The touch image  670   a  is less than or equal to in size the button  670 . 
     For example, if the user touches a touch point  671  which belongs to the button  670 , the second processor  120  (e.g., the touch control circuit) may send a coordinate value of the touch point  671  to the display driving circuit  130  through a control signal. The display driving circuit  130  may determine a reference point  672  of the button  670  including the touch point  671 . The display driving circuit  130  may output the touch image  670   a  having a width  673  and a height  674  on the reference point  672 . In various embodiments, the width  673  and the height  674  of the touch image  670   a  may be less than a width and a height of the touch button  670 , respectively. The user may verify a button that is currently being touched by the user or a button that the user will touch, through the touch image  670   a.    
       FIG. 7  is a flowchart illustrating a method for extracting a partial image from a main image configured with a plurality of images and outputting the extracted image as an additional image according to an embodiment of the present disclosure. 
     Referring to  FIG. 7 , in operation  710 , a display driving circuit  130  of  FIG. 1  may receive main image data about a main image (hereinafter referred to as “combination image”) configured with a plurality of images from a first processor  110  or a second processor  120  of  FIG. 1 . The combination image may be an image in which the display driving circuit  130  may generate an additional image by selecting some of the plurality of images. The combination image may have a form of combining images such as a numeral, an alphabet, a date, a weather icon, a call icon, and a text icon in a specified order. 
     In operation  720 , the display driving circuit  130  may receive a control signal including image selection information from the first processor  110  or the second processor  120 . The image selection information may be information for selecting at least some of the plurality of images included in the combination image. In various embodiments, the image selection information may include a data address, a data size of an image, and the like on a graphic RAM  220  of  FIG. 2 . 
     In operation  730 , the display driving circuit  130  may select some (hereinafter referred to as “output image”) of the plurality of images included in the combination image based on the image selection information. For example, the display driving circuit  130  may select the output image to include time information, weather information, and temperature information. 
     In operation  740 , the display driving circuit  130  may output the selected output image on a display panel  150  of  FIG. 1 . In various embodiments, the display driving circuit  130  may continue outputting the output image, for example, may implement an always-on display. In various embodiments, the display driving circuit  130  may set a specified image (e.g., at least one included in the combination image) to the main image, may combine the output image with the main image, and may output the combined image on the display panel  150 . 
       FIG. 8  is a screen illustrating a process of extracting and outputting a partial image from a combination image configured with a plurality of images according to an embodiment of the present disclosure. 
     Referring to  FIG. 8 , a display driving circuit  130  of  FIG. 1  may receive main image data about a combination image  810  from a first processor  110  or a second processor  120  of  FIG. 1 . The combination image  810  may have a form of combining images such as a numeral, an alphabet, a date, a weather icon, a call icon, and a text icon in a specified order. 
     The display driving circuit  130  may receive a control signal including image selection information from the first processor  110  or the second processor  120 . The image selection information may be information for selecting at least some of the plurality of images included in the combination image. 
     For one example, the display driving circuit  130  may receive a control signal for outputting a digital watch, may select some (e.g., hour information  820   a  and  820   b , classification information  820   c , minute information  820   d  and  820   e , and the like) of images included in the combination image  810 , and may implement the digital watch. The control signal may include information about a location or size where the digital watch is displayed on a screen. 
     For another example, the display driving circuit  130  may receive a control signal including weather information and temperature information via a sensor hub and may combine and output a weather icon  821   a , temperature number values  821   d  and  821   c , a temperature unit  821   d , and the like. 
     According to various embodiments, the display driving circuit  130  may receive a control signal including communication related information via a CP and may display a missed call and message reception information  831 . The display driving circuit  130  may display schedule information  832 , weather information  833 , a digital watch  834 , date information  835 , and the like on a display panel  150  of  FIG. 1 . 
     In  FIG. 8 , an embodiment is exemplified as the output image  830  is displayed in a screen sleep state. However, embodiments are not limited thereto. The display driving circuit  130  may set a specified image (e.g., at least one included in the combination image  810 ) to a main image, may combine the output image with the main image, and may output the combined image on the display panel  150 . 
       FIGS. 9A and 9B  are block diagrams illustrating a configuration of a display driving circuit which performs time calculation according to various embodiments of the present disclosure. 
     Referring to  FIG. 9A , a display driving circuit  930  may include a sub-display driving circuit  940  and a clock generator  910   a . The sub-display driving circuit  940  may receive a signal for a time change of a second hand from the clock generator  910   a . The clock generator  910   a  may include an element such as a crystal resonator. 
     The display driving circuit  930  may receive a main image including time information of hour and minute units via a first channel from a first processor. For example, the display driving circuit  930  may receive main image data for an image, on which an hour and minute of a digital watch is displayed, at intervals of one minute from an AP. 
     The sub-display driving circuit  940  may receive a signal every second from the clock generator  910   a  with reference to a time when the main image data is received. The sub-display driving circuit  940  may generate an additional image based on a signal generated from the clock generator  910   a . The display driving circuit  930  may combine the additional image with a main image generated based on the main image data and may output the combined image. 
     The display driving circuit  930  may perform calculation of a second hand and may display a watch. The first processor or the second processor may not send main image data about a separate main image to the display driving circuit  930  for one minute. 
     A form of a watch output via the display driving circuit  930  may be one of a digital form, an analog form, or a form of simultaneously displaying the digital watch and the analog watch. Additional information about the method for implementing the watch of the second hand via the display driving circuit  130  will be provided with reference to  FIGS. 10, 11, 12, 13, 14 and 15 . 
     Referring to  FIG. 9B , a clock generator  910   b  may be arranged outside the display driving circuit  930 . For example, the clock generator  910   b  may be arranged in the first processor or the second processor or may be arranged in a chip around the display driving circuit  930 . In this case, the display driving circuit  930  may receive a control signal every second over a second channel from the clock generator  910   b . The display driving circuit  930  may perform calculation of a second hand based on the control signal and may generate additional image. The generated additional image may be combined and output with a main image of hour and minute units. 
     According to various embodiments, the clock generator  910   b  may be included in the first processor or the second processor. The first processor or the second processor including the clock generator  910   b  may perform calculation of a second hand and may provide a control signal including the calculated result to the display driving circuit  930  over the second channel In this case, the display driving circuit  930  may combine additional image generated based on the control signal with a main image including hour/minute information without separate calculation of a second hand and may output the combined image. In various embodiments, it is impossible for the display driving circuit  930  to perform decimal point operation, it may include the clock generator  910   b  and may perform calculation about a location of a second hand of an analog watch via a processor (e.g., a touch control circuit) which may perform the decimal point operation. 
     For example, the touch control circuit may perform calculation for a second hand through decimal point operation using an angle. The touch control circuit may provide the calculated result (e.g., information about a location of a pixel, a color of which is changed) to the display driving circuit  930 . The sub-display driving circuit  940  of the display driving circuit  930  may generate an additional image based on the calculated result. 
       FIG. 10  is a block diagram illustrating a configuration of an electronic device for configuring a watch of a second hand according to an embodiment of the present disclosure. In  FIG. 10 , an embodiment is exemplified as it is described that a clock generator is arranged in a display driving unit. However, embodiments are not limited thereto. For example, it is applied that the clock generator is arranged outside the display driving circuit. 
     Referring to  FIG. 10 , a first processor  1010  or a second processor  1020  may provide a main image including hour/minute information of a watch to a display driving circuit  1030  over a first channel  1011 . For example, the display driving circuit  1030  may receive main image data for an image, on which an hour and minute of a digital watch is displayed, at intervals of one minute from an AP. The main image data may be stored in a graphic RAM  1035 . The display driving circuit  1030  may not receive separate main image data for one minute from the first processor  1010  or the second processor  1020 . 
     The sub-display driving circuit  1040  may receive a signal every second from a clock generator  1045  with reference to a specified time (e.g., a time when the main image data is received, a time when the main image data is stored in the graphic RAM  1035 , or a time when a separate control signal is received). The sub-display driving circuit  1040  may perform calculation of a second hand based on a signal generated from the clock generator  1045  and may generate an additional image including the calculated result. 
     The display driving circuit  1030  may combine an additional image including information of a second hand with a main image including information of an hour/minute unit and may output the combined image. The main image may be updated at intervals of one minute, and the additional image may be updated at intervals of one second. 
     Information about implementing a digital watch via the display driving circuit  1030  will be provided with reference to  FIGS. 11 and 12 . Information about implementing an analog watch will be provided with reference to  FIGS. 13 to 15 . 
       FIG. 11  is a drawing illustrating an implementation example of a digital watch of a second hand via a digital driving circuit according to an embodiment of the present disclosure. 
     Referring to  FIG. 11 , a digital watch  1110  of a second hand may be implemented in an electronic device  1101  such as a smartphone or an electronic device  1102  such as a smart watch. An hour/minute unit may be output based on main image data provided from a first processor  1010  (e.g., an AP) or a second processor  1020  (e.g., a CP) in the electronic device  1101  or  1102 . The second hand may be output based on a signal generated by a display driving circuit  1030  of  FIG. 10 . 
     If the display driving circuit  1030  performs all of calculation of an hour/minute/second hand, an amount of calculation may depart from a degree to which calculation may be performed by the display driving circuit  1030 . Incorrect time information may be provided to a user due to a time error of a clock generator  1045  of  FIG. 10 . Since the display driving circuit  1030  performs calculation of a second hand for one minute and since the first processor  1010  or the second processor  1020  performs calculation of an hour/minute unit, the electronic device  1101  or  1102  may reduce a time error which may occur. 
     The digital watch  1110  may be classified into an hour display region  1120  (two digits), a classification region  1130 , a minute display region  1140  (two digits), and a second display region  1150  (two digits). In various embodiments, the digital watch  1110  may be implemented with a watch  1103  of a row division type or a watch  1104  of a seven-segment type. However, embodiments are not limited thereto. For example, various types of digital watches may be applied to the digital watch  1110 . 
     According to various embodiments, at least part of the hour display region  1120 , the classification region  1130 , or the minute display region  1140  may be output through an additional image generated by the sub-display driving unit  1040 . For one example, the classification region  1130  may be repeatedly turned on/off at intervals of one second through an additional image generated by the sub-display driving circuit  1040 . For another example, the minute display region  1140  and the second display region  1150  may be configured to be output at intervals of a specified time (e.g., five minutes) through additional image. 
       FIG. 12  is a block diagram illustrating a process of outputting a digital watch in a sub-display driving circuit according to an embodiment of the present disclosure. 
     Referring to  FIG. 12 , a sub-display driving circuit  1040  of  FIG. 10  may include a time generator  1210 , a control signal unit  1220 , a numeral generator  1230 , and a combiner  1240 . The time generator  1210  may provide time information to the combiner  1240 . The control signal unit  1220  may provide an enable signal to the combiner  1240 . A numeral generator  1230  may provide numerals which configures a digital watch to the combiner  1240 . The combiner  1240  may output the digital watch by combining the signals provided from the time generator  1210 , the control signal unit  1220 , and the numeral generator  1230 . 
     According to various embodiments, the sub-display driving circuit  1040  may be configured to perform only calculation of a second hand using the time generator  1210 , the control signal unit  1220 , the numeral generator  1230 , and the combiner  1240 . A display driving circuit  1030  of  FIG. 10  may receive main image data on which information about an hour/minute is displayed from a first processor  1010  or a second processor  1020  of  FIG. 10 . The sub-display driving circuit  1040  may generate an additional image including information of a second hand, may combine the generated additional image with the main image data, and may output the combined image. 
       FIG. 13  is a drawing illustrating an implementation example of an analog watch according to an embodiment of the present disclosure. 
     Referring to  FIG. 13 , a main image  1310  may include hour information (hour hand)  1310   a  and minute information (minute hand)  1310   b . The main image  1310  may be provided to a display driving circuit  1030  of  FIG. 10  over a first channel  1011  of  FIG. 10  from a first processor  1010  or a second processor  1020  of  FIG. 10 . In various embodiments, the main image  1310  may be updated at intervals of a specified time (e.g., one minute). 
     An additional image  1320  may include second information (second hand)  1320   a . The additional image  1320  may be generated via a sub-display driving circuit  1040  and a clock generator  1045  in the display driving circuit  1030 . 
     The display driving circuit  1030  may combine the main image  1310  with the additional image  1320  and may output an analog watch  1330  on a display panel  1050  of  FIG. 10 . The analog watch  1330  may be output in a state such as a state  1340   a  where a screen of an electronic device such as a smartphone is turned off (e.g., a state where the other pixels except for the analog watch  1330  are turned off) or a state  1340   b  where the analog watch  1330  is output together with a home screen. Alternatively, the analog watch  1330  may be output in a state such as a watch output state  1350   a  of an electronic device such as a smart watch or a state  1350   b  where the analog watch  1330  is output together with a digital watch. 
       FIG. 14  is a block diagram illustrating a detailed configuration of a sub-display driving circuit for implementing an analog watch according to an embodiment of the present disclosure. 
     Referring to  FIG. 14 , a sub-display driving circuit  1401  may include a calculation unit  1410 , a setting unit  1420 , and a drawing unit  1430 . 
     The calculation unit  1410  may receive coordinates Start_X, Start_Y, End_X, and End_Y for information about a start point and an end point to draw a second hand and may calculate parameters (e.g., a slope, change amounts dy and dx, and the like) necessary for applying a specified algorithm (e.g. a Bresenham algorithm) The calculation unit  1410  may set a start point and an end point again such that an upper end or a left side becomes the start point in consideration of a direction where data is drawn. If the slope among the parameters is positive, an absolute value of the slope may be reset as a segment having the same negative slope. 
     The setting unit  1420  may calculate determination parameters to be quicker than the drawing unit  1430  by one line and may store pixel information necessary for drawing a second hand. An X coordinate of a start/end point may be stored in a variable in each line. The setting unit  1420  may update start/end point information in the end of every line to use information about a start/end point stored to be quicker than the drawing unit  1430  by one line in an actually drawn next line. 
     The drawing unit  1430  may set an output value DE as a high level when passing through a coordinate using the corresponding coordinate for a start/end point. The drawing unit  1430  may apply the coordinate to a segment with a negative slope which is identical to a direction where data is drawn without change. Conversely, the drawing unit  1430  may generate an output value DE by resetting a start/end point in consideration of a max width. 
       FIG. 15  is a drawing illustrating a second hand drawing method using a Bresenham algorithm according to an embodiment of the present disclosure. For example, an algorithm using another integer calculation may be used to draw a second hand. 
     Referring to  FIG. 15 , a sub-display driving circuit  1401  of  FIG. 14  may set a start point  1501  of a second hand and an end point  1502  of the second hand. The sub-display driving circuit  1401  may calculate change amounts dx and dy between the start point  1501  and the end point  1502  of the second hand. 
     The sub-display driving circuit  1401  may determine a start point  1510  and an end point  1520  for each line of a pixel based on a clock signal  1530  provided to the sub-display driving circuit  1401 . 
     The number of pixels, colors of which are changed from a start point of a first column, may be determined based on the change amounts dx and dy. A start point of a second column may be the same as an end point of the first column (or a previous point of the end point of the first column) in x-coordinate. 
     According to various embodiments, a method for operating an electronic device, the method may include receiving, by a display driving circuit of the electronic device, main image data over a first channel from a first processor or a second processor of the electronic device, outputting, by the display driving circuit, a main image on a display panel of the electronic device based on the main image data, generating, by the display driving circuit, an additional image different from the main image, merging, by the display driving circuit, the main image with the additional image, and outputting, by the display driving circuit, the merged image on the display panel. 
     According to various embodiments, the generating of the additional image may include generating the additional image associated with the main image data. 
     According to various embodiments, the generating of the additional image may include receiving, by the display driving circuit, a control signal over a second channel from the first processor or the second processor, and generating, by the display driving circuit, the additional image based on the control signal. 
     According to various embodiments, the generating of the additional image may include generating an additional image including a graphic symbol or icon of a type associated with an application which generates the main image data. 
     According to various embodiments, the generating of the additional image may include generating the additional image based on a coordinate value on a screen, the coordinate value included in the control signal. 
     According to various embodiments, the generating of the additional image may include changing at least one of luminance, saturation, or a hue of pixels of a range relative to the coordinate value in the main image data. 
     According to various embodiments, the generating of the additional image may include performing anti-aliasing processing for a peripheral region of the pixels. 
     According to various embodiments, the generating of the additional image may include generating a cursor image which is turned on/off at intervals of a time relative to the coordinate value in the main image data. 
     According to various embodiments, the generating of the additional image may include changing an output of the additional image on a frame-by-frame basis. 
     According to various embodiments, the method for operating the electronic device may further include receiving updated main image data including the additional image from the first processor or the second processor, and outputting the main image based on the updated main image data and stopping outputting of the additional image. 
     According to various embodiments, the receiving of the main image data may include receiving the main image data from an AP of the electronic device, and the receiving of the control signal may include receiving the control signal from at least one of a CP, a touch control circuit, a touch pen control circuit, or a sensor hub of the electronic device. 
     According to various embodiments, the receiving of the main image data may include receiving the main image data via an HiSSI, and the receiving of the control signal may include receiving the control signal via an LoSSI. 
     According to various embodiments, the receiving of the main image data may include receiving main image data including hour information and minute information of a digital watch or an analog watch. 
     According to various embodiments, the generating of the additional image may include generating an additional image including second information associated with the main image data. The outputting of the main image on the display panel may include outputting a digital watch or an analog watch of a second hand by merging the main image based on the main image data with the additional image. The outputting of the digital watch or the analog watch may include outputting the digital watch or the analog watch during a time or while power is supplied to the electronic device. The generating of the additional image may include generating the additional image based on a signal generated every second by a clock generator in the display driving circuit. 
     According to various embodiments, the outputting of the main image data on the display panel may include outputting the digital watch with one of a row division type or a seven-segment type. The outputting of the main image data on the display panel may include drawing a second hand image of the analog watch using a line drawing method according to a Bresenham algorithm. 
       FIG. 16  is a diagram illustrating an electronic device in a network environment, according to an embodiment of the present disclosure. 
     Referring to  FIG. 16 , there is illustrated an electronic device  2301  in a network environment  2300  according to various embodiments. The electronic device  2301  may include a bus  2310 , a processor  2320 , a memory  2330 , an input/output (I/O) I/F  2350 , a display  2360 , and a communication I/F  2370 . According to an embodiment, the electronic device  2301  may not include at least one of the above-described elements or may further include other element(s). 
     For example, the bus  2310  may interconnect the above-described elements  2320  to  2370  and may include a circuit for conveying communications (e.g., a control message and/or data) among the above-described elements. 
     The processor  2320  (e.g., the processor  110  of  FIG. 1 ) may include one or more of a CPU, an AP, or a CP. The processor  2320  may perform, for example, data processing or an operation associated with control and/or communication of at least one other element(s) of the electronic device  2301 . 
     The memory  2330  (e.g., the memory  160  of  FIG. 1 ) may include a volatile and/or nonvolatile memory. For example, the memory  2330  may store instructions or data associated with at least one other element(s) of the electronic device  2301 . According to an embodiment, the memory  2330  may store software and/or a program  2340 . The program  2340  may include, for example, a kernel  2341 , a middleware  2343 , an application programming interface (API)  2345 , and/or an application program (or “application”)  2347 . At least a part of the kernel  2341 , the middleware  2343 , or the API  2345  may be called an “operating system (OS)”. 
     The kernel  2341  may control or manage system resources (e.g., the bus  2310 , the processor  2320 , the memory  2330 , and the like) that are used to execute operations or functions of other programs (e.g., the middleware  2343 , the API  2345 , and the application program  2347 ). Furthermore, the kernel  2341  may provide an I/F that allows the middleware  2343 , the API  2345 , or the application program  2347  to access discrete elements of the electronic device  2301  so as to control or manage system resources. 
     The middleware  2343  may perform a mediation role such that the API  2345  or the application program  2347  communicates with the kernel  2341  to exchange data. 
     Furthermore, the middleware  2343  may process one or more task requests received from the application program  2347  according to a priority. For example, the middleware  2343  may assign the priority, which makes it possible to use a system resource (e.g., the bus  2310 , the processor  2320 , the memory  2330 , or the like) of the electronic device  2301 , to at least one of the application program  2347 . For example, the middleware  2343  may process the one or more task requests according to the priority assigned to the at least one, which makes it possible to perform scheduling or load balancing on the one or more task requests. 
     The API  2345  may be an I/F through which the application  2347  controls a function provided by the kernel  2341  or the middleware  2343 , and may include, for example, at least one I/F or function (e.g., an instruction) for a file control, a window control, image processing, a character control, or the like. 
     The I/O interface  2350  may transmit an instruction or data, input from a user or another external device, to other element(s) of the electronic device  2301 . Furthermore, the I/O interface  2350  may output an instruction or data, received from other element(s) of the electronic device  2301 , to a user or another external device. 
     The display  2360  may include, for example, a liquid crystal display (LCD), an LED display, an OLED display, or a microelectromechanical systems (MEMS) display, or an electronic paper display. The display  2360  may display, for example, various kinds of content (e.g., a text, an image, a video, an icon, a symbol, and the like) to a user. The display  2360  may include a touch screen and may receive, for example, a touch, gesture, proximity, or hovering input using an electronic pen or a portion of a user&#39;s body. 
     The communication I/F  2370  may establish communication between the electronic device  2301  and an external device (e.g., a first external electronic device  2302 , a second external electronic device  2304 , or a server  2306 ). For example, the communication I/F  2370  may be connected to a network  2362  through wireless communication or wired communication to communicate with an external device (e.g., the second external electronic device  2304  or the server  2306 ). 
     The wireless communication may include at least one of, for example, long-term evolution (LTE), LTE-advanced (LTE-A), code division multiple access (CDMA), wideband CDMA (WCDMA), universal mobile telecommunications system (UMTS), wireless broadband (WiBro), or global system for mobile communications (GSM), or the like, as cellular communication protocol. Furthermore, the wireless communication may include, for example, a local area network  2364 . The local area network  2364  may include at least one of a Wi-Fi, a near field communication (NFC), or a GNSS, or the like. The GNSS may include at least one of a global positioning system (GPS), a global navigation satellite system (GLONASS), BeiDou navigation satellite system (hereinafter referred to as “BeiDou”), the European global satellite-based navigation system (Galileo), or the like. In this specification, “GPS” and “GNSS” may be interchangeably used. The wired communication may include at least one of, for example, a universal serial bus (USB), a high definition multimedia interface (HDMI), a recommended standard-232 (RS-232), a plain old telephone service (POTS), or the like. The network  2362  may include at least one of telecommunications networks, for example, a computer network (e.g., local area network (LAN) or wide area network (WAN)), an internet, or a telephone network. 
     Each of the first and second external electronic devices  2302  and  2304  may be a device of which the type is different from or the same as that of the electronic device  2301 . According to an embodiment, the server  2306  may include a group of one or more servers. According to various embodiments, all or a portion of operations that the electronic device  2301  will perform may be executed by another or plural electronic devices (e.g., the electronic devices  2302  and  2304  or the server  2306 ). According to an embodiment, in the case where the electronic device  2301  executes any function or service automatically or in response to a request, the electronic device  2301  may not perform the function or the service internally, but, alternatively additionally, it may request at least a part of a function associated with the electronic device  101  at other device (e.g., the electronic device  2302  or  2304  or the server  2306 ). The other electronic device (e.g., the electronic device  2302  or  2304  or the server  2306 ) may execute the requested function or additional function and may transmit the execution result to the electronic device  2301 . The electronic device  2301  may provide the requested function or service using the received result or may additionally process the received result to provide the requested function or service. To this end, for example, cloud computing, distributed computing, or client-server computing may be used. 
       FIG. 17  is a block diagram of an electronic device according to an embodiment of the present disclosure. 
     Referring to  FIG. 17 , an electronic device  2401  may include, for example, all or a part of the electronic device  241  illustrated in  FIG. 1 . The electronic device  2401  may include one or more processors (e.g., an AP)  2410 , a communication module  2420 , a subscriber identification module (SIM)  2424 , a memory  2430 , a sensor module  2440 , an input device  2450 , a display  2460 , an I/F  2470 , an audio module  2480 , a camera module  2491 , a power management module  2495 , a battery  2496 , an indicator  2497 , and a motor  2498 . 
     The processor  2410  may drive an OS or an application to control a plurality of hardware or software elements connected to the processor  2410  and may process and compute a variety of data. The processor  2410  may be implemented with a system on chip (SoC), for example. According to an embodiment, the processor  2410  may further include a graphics processing unit (GPU) and/or an image signal processor. The processor  2410  may include at least a part (e.g., a cellular module  2421 ) of elements illustrated in  FIG. 17 . The processor  2410  may load and process an instruction or data, which is received from at least one of other elements (e.g., a nonvolatile memory) and may store a variety of data in a nonvolatile memory. 
     The communication module  2420  may be configured the same as or similar to the communication I/F  2370  of  FIG. 16 . The communication module  2420  may include a cellular module  2421 , a Wi-Fi module  2423 , a Bluetooth (BT) module  2425 , a GNSS module  2427  (e.g., a GPS module, a GLONASS module, a BeiDou module, or a Galileo module), an NFC module  2428 , and a radio frequency (RF) module  2429 . 
     The cellular module  2421  may provide voice communication, video communication, a message service, an internet service or the like through a communication network. According to an embodiment, the cellular module  2421  may perform discrimination and authentication of the electronic device  2401  within a communication network using the SIM  2424  (e.g., a SIM card), for example. According to an embodiment, the cellular module  2421  may perform at least a portion of functions that the processor  2410  provides. According to an embodiment, the cellular module  2421  may include a CP. 
     Each of the Wi-Fi module  2423 , the BT module  2425 , the GNSS module  2427 , and the NFC module  2428  may include a processor for processing data exchanged through a corresponding module, for example. According to an embodiment, at least a part (e.g., two or more elements) of the cellular module  2421 , the Wi-Fi module  2423 , the BT module  2425 , the GNSS module  2427 , or the NFC module  2428  may be included within one IC or an IC package. 
     The RF module  2429  may transmit and receive, for example, a communication signal (e.g., an RF signal). The RF module  2429  may include, for example, a transceiver, a power amplifier module (PAM), a frequency filter, a low noise amplifier (LNA), an antenna, or the like. According to an embodiment, at least one of the cellular module  2421 , the Wi-Fi module  2423 , the BT module  2425 , the GNSS module  2427 , or the NFC module  2428  may transmit and receive an RF signal through a separate RF module. 
     The SIM  2424  may include, for example, a card and/or embedded SIM that includes a SIM and may include unique identify information (e.g., IC card identifier (ICCID)) or subscriber information (e.g., international mobile subscriber identity (IMSI)). 
     The memory  2430  (e.g., the memory  2330 ) may include an internal memory  2432  or an external memory  2434 . For example, the internal memory  2432  may include at least one of a volatile memory (e.g., a dynamic RAM (DRAM), a static RAM (SRAM), or a synchronous DRAM (SDRAM)), a nonvolatile memory (e.g., a one-time programmable read only memory (OTPROM), a programmable ROM (PROM), an erasable and programmable ROM (EPROM), an electrically erasable and programmable ROM (EEPROM), a mask ROM, a flash ROM, a flash memory (e.g., a NAND flash memory, or a NOR flash memory), a hard drive, or a solid state drive (SSD). 
     The external memory  2434  may include a flash drive, for example, compact flash (CF), secure digital (SD), micro-SD, mini-SD, extreme digital (xD), multimedia card (MMC), a memory stick, or the like. The external memory  2434  may be functionally and/or physically connected with the electronic device  2401  through various I/Fs. 
     The sensor module  2440  may measure, for example, a physical quantity or may detect an operation state of the electronic device  2401 . The sensor module  2440  may convert the measured or detected information to an electric signal. The sensor module  2440  may include at least one of a gesture sensor  2440 A, a gyro sensor  2440 B, a barometric pressure sensor  2440 C, a magnetic sensor  2440 D, an acceleration sensor  2440 E, a grip sensor  2440 F, a proximity sensor  2440 G, a color sensor  2440 H (e.g., red, green, blue (RGB) sensor), a biometric sensor  2440 I, a temperature/humidity sensor  2440 J, an illuminance sensor  2440 K, or an ultraviolet (UV) sensor  2440 M. Even though not illustrated, additionally or alternatively, the sensor module  2440  may include, for example, an E-nose sensor, an electromyography sensor (EMG) sensor, an electroencephalogram (EEG) sensor, an electrocardiogram (ECG) sensor, an infrared (IR) sensor, an iris sensor, and/or a fingerprint sensor. The sensor module  2440  may further include a control circuit for controlling at least one or more sensors included therein. According to an embodiment, the electronic device  2401  may further include a processor which is a part of the processor  2410  or independent of the processor  2410  and is configured to control the sensor module  2440 . The processor may control the sensor module  2440  while the processor  2410  remains at a sleep state. 
     The input device  2450  may include, for example, a touch panel  2452 , a (digital) pen sensor  2454 , a key  2456 , or an ultrasonic input unit  2458 . The touch panel  2452  may use at least one of capacitive, resistive, infrared and ultrasonic detecting methods. Also, the touch panel  2452  may further include a control circuit. The touch panel  2452  may further include a tactile layer to provide a tactile reaction to a user. 
     The (digital) pen sensor  2454  may be, for example, a portion of a touch panel or may include an additional sheet for recognition. The key  2456  may include, for example, a physical button, an optical key, a keypad, or the like. The ultrasonic input device  2458  may detect (or sense) an ultrasonic signal, which is generated from an input device, through a microphone (e.g., a microphone  2488 ) and may check data corresponding to the detected ultrasonic signal. 
     The display  2460  (e.g., the display  2360 ) may include a panel  2462 , a hologram device  2464 , or a projector  2466 . The panel  2462  may be configured the same as or similar to the display  2360  of  FIG. 16 . The panel  2462  may be implemented to be flexible, transparent or wearable, for example. The panel  2462  and the touch panel  2452  may be integrated into a single module. The hologram device  2464  may display a stereoscopic image in a space using a light interference phenomenon. The projector  2466  may project light onto a screen so as to display an image. The screen may be arranged inside or outside the electronic device  2401 . According to an embodiment, the display  2460  may further include a control circuit for controlling the panel  2462 , the hologram device  2464 , or the projector  2466 . 
     The I/F  2470  may include, for example, an HDMI  2472 , a USB  2474 , an optical I/F  2476 , or a D-subminiature (D-sub)  2478 . The I/F  2470  may be included, for example, in the communication I/F  2370  illustrated in  FIG. 16 . Additionally or alternatively, the I/F  2470  may include, for example, a mobile high definition link (MHL) I/F, an SD card/MMC I/F, or an infrared data association (IrDA) standard I/F. 
     The audio module  2480  may convert a sound and an electrical signal in dual directions. At least a part of the audio module  2480  may be included, for example, in the I/O interface  2350  illustrated in  FIG. 16 . The audio module  2480  may process, for example, sound information that is input or output through a speaker  2482 , a receiver  2484 , an earphone  2486 , or a microphone  2488 . 
     The camera module  2491  for shooting a still image or a video may include, for example, at least one image sensor (e.g., a front sensor or a rear sensor), a lens, an image signal processor (ISP), or a flash (e.g., an LED or a xenon lamp). 
     The power management module  2495  may manage, for example, power of the electronic device  2401 . According to an embodiment, a power management IC (PMIC) a charger IC, or a battery or fuel gauge may be included in the power management module  2495 . The PMIC may have a wired charging method and/or a wireless charging method. The wireless charging method may include, for example, a magnetic resonance method, a magnetic induction method or an electromagnetic method and may further include an additional circuit, for example, a coil loop, a resonant circuit, a rectifier, or the like. The battery gauge may measure, for example, a remaining capacity of the battery  2496  and a voltage, current or temperature thereof while the battery is charged. The battery  2496  may include, for example, a rechargeable battery or a solar battery. 
     The indicator  2497  may display a specific state of the electronic device  2401  or a part thereof (e.g., the processor  2410 ), such as a booting state, a message state, a charging state, and the like. The motor  2498  may convert an electrical signal into a mechanical vibration and may generate a vibration effect, a haptic effect, or the like. Even though not illustrated, a processing device (e.g., a GPU) for supporting a mobile TV may be included in the electronic device  2401 . The processing device for supporting a mobile TV may process media data according to the standards of digital multimedia broadcasting (DMB), digital video broadcasting (DVB), MediaFlo™, or the like. 
     Each of the above-mentioned elements may be configured with one or more components, and the names of the elements may be changed according to the type of the electronic device. The electronic device according to various embodiments may include at least one of the above-mentioned elements, and some elements may be omitted or other additional elements may be added. Furthermore, some of the elements of the electronic device according to various embodiments may be combined with each other so as to form one entity, so that the functions of the elements may be performed in the same manner as before the combination. 
     According to various embodiments, an electronic device may include a first processor, a second processor configured to be independent of the first processor and to perform calculation for a function, a display driving circuit, and a display panel, wherein the display driving circuit receives main image data over a first channel from the first processor or the second processor and outputs a main image based on the main image data, and wherein the display driving circuit generates an additional image different from the main image, merges the main image with the additional image, and outputs the merged image on the display panel. 
     According to various embodiments, the display driving circuit receives a control signal over a second channel from the first processor or the second processor and generates the additional image based on the control signal. 
     According to various embodiments, the display driving circuit may include an I/F module configured to receive data from the first processor or the second processor, a sub-display driving circuit configured to generate the additional image, a multiplexer configured to merge the main image with the additional image, and a source driver and a gate driver configured to drive the display panel. 
     According to various embodiments, the display driving circuit may further include a first graphic RAM configured to store the main image data, and an image processing module configured to convert the main image data. 
     According to various embodiments, the I/F module may include a high speed I/F configured to receive the main image data, and a low speed I/F configured to receive a control signal from the first processor or the second processor. 
     According to various embodiments, the display driving circuit may further include a clock generator configured to provide a clock signal to the sub-display driving circuit. 
     According to various embodiments, the sub-display driving circuit may include a second graphic RAM configured to be independent of the first graphic RAM, and the second graphic RAM stores at least part of the main image data. 
     According to various embodiments, the sub-display driving circuit may further include a magnification adjusting unit configured to adjust a magnification of the image data stored in the second graphic RAM. 
     According to various embodiments, the sub-display driving circuit receives data corresponding to at least part of the main image data from at least one of the I/F module, the first graphic RAM, or the image processing module. 
     According to various embodiments, the sub-display driving circuit generates the additional image by adjusting an output form of the image data stored in the second graphic RAM. 
     According to various embodiments, the sub-display driving circuit determines a range of the main image data to be stored in the second graphic RAM in response to an input of a user of the electronic device. 
     According to various embodiments, the sub-display driving circuit dynamically changes the additional image in output size based on at least one of a type of the input or duration. 
     The term “module” used in this disclosure may represent, for example, a unit including one or more combinations of hardware, software and firmware. For example, the term “module” may be interchangeably used with the terms “unit”, “logic”, “logical block”, “component” and “circuit”. The “module” may be a minimum unit of an integrated component or may be a part thereof. The “module” may be a minimum unit for performing one or more functions or a part thereof. The “module” may be implemented mechanically or electronically. For example, the “module” may include at least one of an application-specific IC (ASIC) chip, a field-programmable gate array (FPGA), and a programmable-logic device for performing some operations, which are known or will be developed. 
     At least a portion of an apparatus (e.g., modules or functions thereof) or a method (e.g., operations) according to various embodiments may be, for example, implemented by instructions stored in a computer-readable storage media in the form of a program module. The instruction, when executed by a processor (e.g., the processor  2320 ), may cause the one or more processors to perform a function corresponding to the instruction. The computer-readable storage media, for example, may be the memory  2330 . 
     The computer-readable storage media according to various embodiments may store a program for executing an operation in which a communication module receives an application package from an external device and provides the application package to a normal module of a processor, an operation in which the normal module determines whether a secure application is included in at least a portion of the application package, and an operation in which the secure module of the processor installs the secure application in the secure module or in a memory associated with the secure module. 
     The computer-readable storage media may include a hard disk, a floppy disk, a magnetic media (e.g., a magnetic tape), an optical media (e.g., a compact disc ROM (CD-ROM) and a DVD), a magneto-optical media (e.g., a floptical disk), and hardware devices (e.g., a ROM, a RAM, or a flash memory). Also, a program instruction may include not only a mechanical code such as things generated by a compiler but also a high-level language code executable on a computer using an interpreter. The above-mentioned hardware devices may be configured to operate as one or more software modules to perform operations according to various embodiments, and vice versa. 
     Modules or program modules according to various embodiments may include at least one or more of the above-mentioned elements, some of the above-mentioned elements may be omitted, or other additional elements may be further included therein. Operations executed by modules, program modules, or other elements according to various embodiments may be executed by a successive method, a parallel method, a repeated method, or a heuristic method. Also, a part of operations may be executed in different sequences, omitted, or other operations may be added. 
     According to various embodiments, the display driving circuit of the electronic device may generate and output an additional image for providing additional information to the user through simple calculation. 
     According to various embodiments, the electronic device may reduce the number of times of driving the AP and may provide a fast response speed. 
     According to various embodiments, the electronic device may output a digital watch or an analog watch which may provide an output of a second hand, and may implement an always-on display by reducing the number of times of driving the AP and reducing battery consumption. 
     According to various embodiments, the electronic device may quickly output a zoomed-in image for a portion the user wants using the display driving circuit and may reduce the number of times of driving the AP or a time when the AP is driven. 
     While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.