Receiving host, conditional access system, digital television and operation method thereof

Abstract

The invention discloses a receiving host, a conditional access system, a digital television and an operation method thereof, and the receiving host comprises a front-end processing module which is used for receiving a high-frequency digital television signal, carrying out the tuning and demodulation of the high-frequency digital television signal, generating a transmission stream, and transmitting the transmission stream to an interface control module; and the interface control module is used for identifying the type of the target decryption card when the target decryption card is detected to be inserted, setting configuration information of the interface control module according to the type of the target decryption card and establishing communication between the target decryption card and the interface control module, so that the target decryption card descrambles the transport stream and transmits the transport stream to the interface control module. The obtained descrambled transmission stream is transmitted to the interface control module; and the rear-end processing module is used for decoding the descrambled transport stream and outputting an audio stream and a video stream to be played. Therefore, market requirements of different regions can be met, and machine-card separation is adopted, so that the cost is reduced, and the universality of the digital television is improved.

Description

Technical Field

[0001] The present application relates to the technical field of digital television, and in particular to a receiving host, a conditional access system, a digital television and an operating method thereof. Background Art

[0002] With the increasing popularity of digital television, the Conditional Access System (CAS) is the most important component in the development of digital television and the key to ensuring the security of digital television programs. There are currently many technical standards for the conditional access system, such as the Digital Video Broadcasting (DVB) technology mainly used in Europe, the Point of Deployment (POD) technology used in North America, and the Smart Card technology used in Japan.

[0003] In the related technology, current digital televisions generally only include one conditional reception circuit, which cannot meet the market demands of different regions at the same time. Moreover, different regions require dedicated digital television chips, resulting in high costs. In particular, the set-top boxes used in some regions are still integrated with the machine and the card. Therefore, they need to be replaced as a whole every time the technology is updated, which makes the cost expensive and reduces universality. Summary of the invention

[0004] The present application proposes a receiving host, a conditional reception system, a digital television and an operating method thereof, which can meet the market demands of different regions and improve the versatility of digital television chips; and the use of a machine-card separation method can also make the digital television functions more universal, thereby reducing costs and improving the universality of the digital television.

[0005] To achieve the above purpose, the technical solution of this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a receiving host, the receiving host comprising a front-end processing module, an interface control module and a back-end processing module, wherein:

[0007] The front-end processing module is used to receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transmission stream and transmit it to the interface control module;

[0008] The interface control module is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module according to the type of the target decryption card, and establish communication between the target decryption card and the interface control module, so that the target decryption card performs descrambling processing on the transmission stream, and transmits the obtained descrambled transmission stream to the interface control module;

[0009] The back-end processing module is used to decode the descrambled transport stream and output the audio stream and video stream to be played.

[0010] In a second aspect, an embodiment of the present application provides a conditional access system, which includes a target decryption card and a receiving host as described in the first aspect, and the target decryption card is connected to an interface control module of the receiving host.

[0011] In a third aspect, an embodiment of the present application provides a digital television, which includes a target decryption card and a receiving host as described in the first aspect, and the target decryption card is connected to an interface control module of the receiving host.

[0012] In a fourth aspect, an embodiment of the present application provides a method for operating a digital television, the method comprising:

[0013] Receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transmission stream and transmit it to the interface control module;

[0014] When the interface control module detects that the target decryption card is inserted, it identifies the type of the target decryption card, sets the configuration information of the interface control module according to the type of the target decryption card, and establishes communication between the target decryption card and the interface control module;

[0015] Descrambling the transport stream based on the target decryption card to obtain a descrambled transport stream, and transmitting the descrambled transport stream to the interface control module;

[0016] Decode the descrambled transport stream and output the audio and video streams to be played.

[0017] The embodiment of the present application provides a receiving host, a conditional access system, a digital television and an operating method thereof. In the receiving host, a front-end processing module is used to receive a high-frequency digital television signal, tune and demodulate the high-frequency digital television signal, generate a transmission stream and transmit it to an interface control module; the interface control module is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module according to the type of the target decryption card and establish communication between the target decryption card and the interface control module, so that the target decryption card descrambles the transmission stream and transmits the obtained descrambled transmission stream to the interface control module; the back-end processing module is used to decode the descrambled transmission stream and output the audio stream and video stream to be played. In this way, through the interface control module in the receiving host, various types of decryption cards can be compatible, thereby meeting the market demands of different regions and improving the versatility of the digital TV chip; and by separating the machine and the card, part of the circuit used for descrambling processing is integrated in the external decryption card, which can also make the digital TV function tend to be universal, and also fully consider the metastable phenomenon that may be generated when the receiving host and the external decryption card perform data interaction, thereby improving the stability; in this way, the universality of digital TV can be improved while reducing the cost, which is conducive to the development of digital TV. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a circuit structure of a receiving host provided in an embodiment of the present application Figure 1 ;

[0019] Figure 2 A schematic diagram of a circuit structure of a receiving host provided in an embodiment of the present application Figure 2 ;

[0020] Figure 3 A schematic diagram of a circuit structure of a receiving host provided in an embodiment of the present application Figure 3 ;

[0021] Figure 4 A schematic diagram of the circuit structure of a PCMCIA interface provided in an embodiment of the present application;

[0022] Figure 5 A schematic diagram of a circuit structure for detecting insertion of a target decryption card provided in an embodiment of the present application;

[0023] Figure 6 A schematic diagram of the circuit structure of a conditional access system provided in an embodiment of the present application;

[0024] Figure 7 A detailed structural diagram of a conditional access system provided in an embodiment of the present application;

[0025] Figure 8A flowchart of a method for operating a digital television provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to enable a more detailed understanding of the features and technical contents of the embodiments of the present application, the implementation of the embodiments of the present application is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present application.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0028] It should also be noted that the terms "first\second\third" involved in the embodiments of the present application are only used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0029] It should also be noted that in the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it can be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict.

[0030] To facilitate understanding of the technical solutions of the embodiments of the present application, the relevant technologies of the embodiments of the present application are described below. The following related technologies can be arbitrarily combined with the technical solutions of the embodiments of the present application as optional solutions, and they all belong to the protection scope of the embodiments of the present application.

[0031] As digital TV becomes more and more popular, general digital TV viewing users can directly connect traditional TV to set-top-box (STB) to receive digital TV signals. Digital TV signals are divided into free-to-air channels and encrypted paid channels. For encrypted paid channels, users need to use conditional access system (CAS) with smart card to decrypt before viewing.

[0032] Among a series of standards for digital TV broadcasting, the conditional access system is a system used to control users' access to broadcast services and TV programs. The conditional access system can ensure that only authorized and paid users can watch the selected TV broadcast programs, while unpaid users cannot obtain information. The conditional access system is the basis for digital TV to realize value-added services such as video on demand and TV shopping, and is also the basis for the development of digital TV to a higher level.

[0033] For example, a typical conditional access system is mainly composed of an encryption and descrambling module, an encryption and decryption module, and an interactive management module. Among them, the core encryption and descrambling technology currently has three main technical standards: one is the Simul crypt technical standard defined by DVB, the second is the Multi Crypt technical standard defined by DVB, and the third is the POD technical standard defined by the North American digital cable standard (Open Cable). The following is a description of the relevant technologies for the three technical standards.

[0034] For DVB simulcrypt technology, it can refer to the technology that multiple different CAS manufacturers use a common scrambling and descrambling algorithm and the same control word (CW) in the same network, so that multiple different CAS can work together. The universal descrambling algorithm system and the CAS of a certain CAS manufacturer are integrated in the host at the receiving end. In this way, when receiving the program, the smart card provided by the manufacturer can be accessed through the ISO-7816 standard interface (Conditional Access, CA). The smart card implements the decryption function and extracts the key information (such as control word) required for descrambling the code stream to the descrambling module to descramble the program. Simulcrypt technology is to achieve technology selection and competition from the perspective of digital TV operators. In the same network, different CAS share program information. CAS manufacturers that implement simulcrypt can develop their own different entitlement control messages (ECM) and entitlement management messages (EMM) and program information for reuse, but must follow the universal scrambling algorithm specified by DVB technology.

[0035] For DVB multi-crypto technology, conditional reception can be realized from the user terminal. Its basic idea is to concentrate descrambling, CA and other proprietary functions that need to be kept confidential in a detachable CA module (or "PC card"), so that the host function can be universal. The host only needs to include tuner, demodulator, decoder, demultiplexer and other modules, and has the function of receiving unscrambled or descrambled MPEG-2 audio and video data. Multi-crypto technology defines a common interface (CI) between the host and CA module or uses Universal Serial Bus (USB) for connection and communication. Users can watch these programs by simply inserting the corresponding CA module into the common interface. Multi-crypto technology simplifies the design of digital TV in terms of function. The set-top box does not need to include descrambling and decryption control modules. It only needs to design a universal interface that complies with the multi-crypto specification, and can choose the multi-crypto CA module of any CA manufacturer.

[0036] For POD technology, it can be the security module (i.e. PC card) standard specification led by CableLabs in the United States. This is an improved and expanded conditional access module (CAM). The POD module is equipped with all functions related to confidentiality, including authentication circuits and key data, descrambling circuits and media access control (MAC) layer circuits of the limited transmission data service interface specification. The interface between the POD module and the set-top box host is specified by PODMIS, including the out-of-band (OOB) interface of the host out-of-band demodulator and transmitter and the intent-based network (IBN) interface for the host in-band demodulator and transmitter.

[0037] In summary, these three technologies are used in the field of digital TV broadcasting in different countries and regions. They are of great significance to the program authorization, audience management and performance improvement of digital TV. Among them, DVB simulcrypt technology standardizes the encryption and descrambling algorithms and key transfer framework, so that different CAS can run on the same encryption / descrambling module. However, the flexibility and openness of the DVB simulcrypt technology standard are still very limited. For example, while it opens the general scrambling algorithm, it limits the diversity of scrambling algorithms; because different CA software needs to be embedded in the set-top box for different CAS, a set-top box can generally only be bundled to receive programs encrypted by a specific CAS, so users have the risk of changing the set-top box. With DVB multi-crypt technology and POD technology, from the user's perspective, they will not be completely bound to this CA because of purchasing a set-top box of a CA. The same set-top box can receive programs scrambled and controlled by any CA system. When choosing to change the CA, you only need to replace the corresponding CA module, and the set-top box can remain unchanged, thus reflecting the idea of ​​"separation of machine and card", and the system is more flexible.

[0038] However, with the gradual maturity of digital technology, the demand for digital TV chips is very large. The conditional access system is the most important component in the development of digital TV and is the key to ensuring the security of digital TV programs. However, different countries and regions have multiple protocol standards. For example, DVB-CI technology is mainly used in Europe, POD technology is used in North America, and smart card technology is used in Japan. However, the digital TV of related technologies generally only contains one conditional access circuit, which cannot meet the market needs of different regions at the same time. Different regions use their own technical solutions and require dedicated digital TV chips, resulting in high costs. In addition, the development of digital TV standards is rapid. At present, many set-top boxes used in China are integrated with the machine and card. Therefore, the entire set-top box needs to be replaced every time the technology is updated, which is very expensive. If the machine and card are separated, the CA function is integrated into an external dedicated module, and the card is inserted, the system is more flexible and convenient. However, both CI cards and POD cards adopt the PC card (Personal Computer Memory Card International Association, PCMCIA) standard. When the card is inserted or the card is powered off, the slot and the card must use the "memory only" interface. When the card is powered on, the system reads the card information structure (Card Information Structure, CIS) on the card. If the card is found to be a CI card or POD card, the card can be configured to a custom interface mode and the interface signal will be switched to a different function. However, in this process, the direction and value of the interface signal will change, which may easily lead to instability.

[0039] Based on this, the present embodiment provides a receiving host, a conditional access system, a digital television and an operation method thereof, wherein the receiving host comprises a front-end processing module, an interface control module and a back-end processing module. The front-end processing module is used to tune and demodulate the high-frequency digital television signal, generate a transmission stream and transmit it to the interface control module; the interface control module is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module according to the type of the target decryption card and establish communication between the target decryption card and the interface control module, so that the target decryption card performs descrambling processing on the transmission stream, and transmits the obtained descrambled transmission stream to the interface control module; the back-end processing module is used to decode the descrambled transmission stream and output the audio stream and video stream to be played. In this way, through the interface control module in the receiving host, various types of decryption cards can be compatible, so as to meet the market demands of different regions and improve the universality of the digital TV chip; and by adopting the machine-card separation method, part of the circuit used for descrambling processing is integrated in the external decryption card, which can also make the digital TV function tend to be universal; in addition, after the communication link is established between the target decryption card and the interface control module, the interface control module does not immediately obtain the interface signal of the target decryption card, but starts to obtain the corresponding interface signal after a period of time through the counter counting, thereby fully considering the metastable phenomenon that may be generated when the receiving host and the external decryption card perform data interaction, and improving the stability of the interface signal; in this way, the universality of digital TV can be improved while reducing the cost, which is conducive to the development of digital TV.

[0040] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0041] In one embodiment of the present application, Figure 1 A schematic diagram of a circuit structure of a receiving host provided in an embodiment of the present application Figure 1 .like Figure 1 As shown, the receiving host 10 may include a front-end processing module 101, an interface control module 102 and a back-end processing module 103, wherein:

[0042] The front-end processing module 101 is used to receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transport stream (TS) and transmit it to the interface control module 102;

[0043] The interface control module 102 is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module 102 according to the type of the target decryption card, and establish communication between the target decryption card and the interface control module 102, so that the target decryption card descrambles the transmission stream, and transmits the obtained descrambled transmission stream to the interface control module 102;

[0044] The back-end processing module 103 is used to decode the descrambled transport stream and output the audio stream and video stream to be played.

[0045] In the embodiment of the present application, the receiving host 10 can be applied to a digital television or a set-top box, and can also be called a "digital television receiver (DTV Receiver)" or simply a "host". Here, the receiving host 10 has tuning, demodulation and decoding functions, and part of the circuit used for descrambling processing has been moved to the target decryption card, thereby realizing "machine-card separation".

[0046] In the embodiment of the present application, the target decryption card can be different types of decryption cards, which can adapt to multiple protocol standards, such as the DVB-CI technical standard used in Europe, the POD technical standard used in North America, the smart card technical standard used in Japan, etc. In other words, through the interface control module 102 in the receiving host 10, multiple types of decryption cards can be compatible, thereby meeting the market needs of different regions and improving the versatility of the digital TV chip.

[0047] In the embodiment of the present application, the interface control module 102 is compatible with multiple types of decryption cards, so that the receiving host 10 can also adapt to multiple conditional reception modes. Specifically, the corresponding target decryption card can be selected and inserted according to the current market demand. At this time, the configuration information of the interface control module 102 is set according to the type of the target decryption card and the communication between the target decryption card and the interface control module 102 is established, so that one of the conditional reception modes can be selected from the multiple conditional reception modes to be implemented.

[0048] In some embodiments, Figure 1 Based on the receiving host 10 shown, see Figure 2 , the front-end processing module 101 may include a tuning module 1011 and a demodulation module 1012, wherein:

[0049] The tuning module 1011 is used to receive high-frequency digital television signals and convert the high-frequency digital television signals into intermediate-frequency digital television signals;

[0050] The demodulation module 1012 is used to receive the intermediate frequency digital television signal, demodulate the intermediate frequency digital television signal, generate a transport stream and transmit it to the interface control module 102 .

[0051] In the embodiment of the present application, the tuning module (Tuner) may refer to a tuner (or a tuning chip), which may also be referred to as a "high-frequency head". For example, the high-frequency head here may be a dual high-frequency head integrating analog, cable digital television, and terrestrial digital television to improve the practicality and applicability of digital television.

[0052] In addition, for the tuning module 1011, in digital television, signals of different programs use different carrier frequency bands. The tuning module 1011 mainly performs high-frequency amplification and mixing on the carrier signal to make a difference frequency between the carrier signal and the local oscillator signal, thereby converting the RF carrier signal into an intermediate frequency carrier signal.

[0053] In the embodiment of the present application, the demodulation module (Demod) may refer to a demodulator (or a demodulation chip), which contains multiple modulation and demodulation components and an analog-to-digital converter (ADC), so as to provide demodulation of different formats and output a transmission stream. Among them, the ADC can support high-speed analog-to-digital conversion with low latency.

[0054] That is to say, in the embodiment of the present application, the function of the tuner is to receive high-frequency digital television signals, select channels, amplify high-frequency signals, and perform frequency conversion processing, and then after demodulation by the demodulation module, the output digital signal is a transport stream, i.e., a TS stream. For example, it can be a digital signal transport stream in units of "frames", and each frame of digital signals contains signals such as a synchronization header, data, and an end.

[0055] In some embodiments, see Figure 2 , the backend processing module 103 may include a demultiplexing module 1031 and a content decryption module 1032, wherein:

[0056] The demultiplexing module 1031 is used to receive the descrambled transport stream sent by the interface control module 102, demultiplex the descrambled transport stream, and generate a demultiplexed transport stream;

[0057] The content decryption module 1032 is used to receive the demultiplexed transport stream, and when it is determined that the demultiplexed transport stream has been encrypted, decrypt the demultiplexed transport stream and output the audio stream and video stream to be played.

[0058] In the embodiment of the present application, the demultiplexing module (Demux) may refer to a demultiplexer (or a demultiplexing chip) for receiving the descrambled transport stream sent by the interface control module 102, which mainly provides the digital television with the function of demultiplexing and recording the transport stream based on the audio and video compression standard MPEG-2 formulated by the Moving Pictures Experts Group (MPEG). Specifically, the transport stream generally contains multiple audio and video streams and some data information. The demultiplexing module 1031 is used to distinguish different TV programs, extract the corresponding audio, video streams and data streams and send them to the MPEG-2 decoder and the corresponding analysis circuit to complete the restoration of digital information.

[0059] In the embodiment of the present application, the encryption processing here may refer to content control (Context Control, CC) encryption processing, and thus the content decryption module 1032 may also be referred to as a "CC decryption module", which is mainly used to determine whether CC encryption processing exists in the demultiplexed transmission stream; if CC encryption processing exists, then the transmission stream needs to be subjected to CC decryption processing to obtain clear audio and video streams.

[0060] It should be noted that in the embodiment of the present application, if it is determined that there is no encryption processing in the demultiplexed transport stream, then the transport stream can be directly output, that is, a clear audio stream and video stream can be obtained.

[0061] It should also be noted that, in the embodiment of the present application, the receiving host 10 may also include an audio playback module and a video display module ( Figure 2 The audio playback module is used to play the obtained audio stream; and the video display module is used to display the obtained video stream.

[0062] In the embodiment of the present application, the audio playback module can be implemented by a power amplifier circuit and a speaker.

[0063] In an embodiment of the present application, the video display module can be implemented by a driving module and a display screen. For example, the driving module can be a low voltage differential signal transmission (LVDS) module, and the display screen can be a liquid crystal screen. The LVDS module drives the liquid crystal screen to display the video stream.

[0064] In some embodiments, Figure 2 Based on the receiving host 10 shown, see Figure 3 , the interface control module 102 may include a first interface P1, wherein:

[0065] The interface control module 102 is used to set the first configuration information of the interface control module 102 according to the first type of card and establish communication between the first type of card and the interface control module 102 when it detects that the target decryption card is inserted into the first interface P1 and identifies that the target decryption card is a first type of card, so that the first type of card descrambles the transmission stream and transmits the obtained descrambled transmission stream to the interface control module 102.

[0066] In the embodiment of the present application, the first type of card may include a first smart card, that is, the first type of card refers to a decryption card based on smart card technology. Exemplarily, the first type of card is applicable to Japan.

[0067] In the embodiment of the present application, if a first type of card is inserted into the first interface P1, the first configuration information of the interface control module 102 can be set to match the first type of card, and communication between the first type of card and the interface control module 102 can be established.

[0068] That is to say, in an embodiment of the present application, the first configuration information of the interface control module 102 is set according to the first type of card, so that the first configuration information of the interface control module 102 matches the first type of card, thereby establishing communication between the first type of card and the interface control module 102; based on the communication between the two, the interface control module 102 can send the authorization information in the transmission stream to the first type of card through the first interface P1, and then the first type of card decrypts the authorization information, obtains the first key and transmits the first key to the first interface P1; after the interface control module 102 receives the first key, it descrambles the transmission stream according to the first key, thereby obtaining a descrambled transmission stream.

[0069] It should be noted that in the embodiment of the present application, the authorization information here may include authorization control information (ECM) and authorization management information (EMM), but is not specifically limited.

[0070] In some embodiments, see Figure 3 , the interface control module 102 may further include a second interface P2, wherein:

[0071] The interface control module 102 is used to set the second configuration information of the interface control module 102 according to the second type card and establish communication between the second type card and the interface control module 102 when it detects that the target decryption card is inserted into the second interface P2 and identifies that the target decryption card is a second type card, so that the second type card descrambles the transmission stream and transmits the obtained descrambled transmission stream to the interface control module 102.

[0072] In the embodiment of the present application, the second type of card includes at least one of the following: a decryption card based on digital television broadcasting and a decryption card based on a configuration point, wherein the decryption card based on digital television broadcasting can be called a DVB CI card, and the decryption card based on a configuration point can be called a POD card.

[0073] For example, for the second type of card, the DVB CI card is applicable to Europe, and the POD card is applicable to North America.

[0074] In the embodiment of the present application, if a second type of card is inserted into the second interface P2, the second configuration information of the interface control module 102 can be set to match the second type of card, and communication between the second type of card and the interface control module 102 can be established.

[0075] That is to say, in the embodiment of the present application, the second configuration information of the interface control module 102 is set according to the second type of card, so that the second configuration information of the interface control module 102 matches the second type of card, thereby establishing communication between the second type of card and the interface control module 102; based on the communication between the two, the second type of card can receive the transmission stream and extract the authorization information in the transmission stream, and then decrypt the authorization information. After obtaining the second key, the transmission stream can be descrambled according to the second key, thereby obtaining the descrambled transmission stream and transmitting the descrambled transmission stream to the second interface P2.

[0076] In a specific implementation, the second type of card includes not only the conditional access module but also a second smart card, and the conditional access module includes a third interface, and the third interface is used to insert the second smart card. The conditional access module can receive the transmission stream and extract the authorization information in the transmission stream, and send the authorization information in the transmission stream to the second smart card; then the second smart card receives the authorization information in the transmission stream and decrypts the authorization information to obtain the second key, and transmits the second key to the conditional access module; after the conditional access module receives the second key, it can descramble the transmission stream according to the second key, and transmit the descrambled transmission stream to the interface control module 102.

[0077] In the embodiment of the present application, both the first key and the second key may refer to a control word (ControlWord, CW). Here, the control word may be used as a key to perform descrambling processing on the transport stream.

[0078] In the embodiment of the present application, the interface control module 102 is connected to the conditional access module via the second interface P2. The conditional access module mainly integrates the processing of the entitlement control information (ECM) and entitlement management information (EMM) in the conditional access technology directly into an external module, thereby realizing the separation of the card and the machine, making the functions of the digital television more universal.

[0079] It should be noted that, in the embodiment of the present application, when it is detected that the target decryption card is inserted into the second interface P2, the target decryption card can be identified as a second type card. Specifically, after the card is powered on, the card information structure of the target decryption card is obtained, and then the type of the target decryption card can be determined according to the card information structure. Exemplarily, it can be determined whether the target decryption card is a DVB CI card or a POD card according to the card information structure, so that the most appropriate configuration information can be selected for the interface control module 102 according to the card information structure.

[0080] It should also be noted that in the embodiment of the present application, there is a matching standard interface between the receiving host 10 and the target decryption card, so that the target decryption card can be connected to the receiving host 10 to achieve an electrical connection between the target decryption card and the receiving host 10. A gold finger method can be used here, such as a PCMCIA standard interface, or an interface such as USB can also be used.

[0081] Exemplarily, a card slot matching the target decryption card may be provided on the receiving host 10. Exemplarily, the target decryption card may be made into a rectangular shape with the above-mentioned interface at one end. An inner concave card slot matching the rectangular shape may be provided in the interface control module 102 of the receiving host 10. The target decryption card may be inserted into the card slot to enable the target decryption card to be inserted into the corresponding interface.

[0082] In the embodiment of the present application, taking the second interface P2 for inserting the second type card as an example, the second interface P2 may be a common interface (CI). In some embodiments, the second interface P2 may be an interface using the PCMCIA standard, which may be referred to as a "PCMCIA interface".

[0083] For example, Figure 4 A schematic diagram of the circuit structure of a PCMCIA interface provided in an embodiment of the present application. Figure 4As shown, the PCMCIA interface 40 may include a bridge module (Bridge) 401, a control interface (CTRL) 402, an interrupt interface (Interrupt) 403, and an Advanced Peripheral Bus (APB) register interface (APB REG) 404. The bridge module 401 is used to bridge the APB register interface 404 with the command interface, such as the control interface 402 and the interrupt interface 403.

[0084] In the embodiment of the present application, for the PCMCIA interface 40, two interfaces are defined: one is a transport stream interface based on MPEG-2, and the other is a command interface.

[0085] The transport stream interface can support bidirectional MPEG-2 data stream transmission between the second type card and the receiving host 10. The demodulated data can be transmitted to the second type card for descrambling through the transport stream interface, and then the second type card transmits the CA descrambled code stream back to the receiving host 10 through the transport stream interface. The transport stream interface includes two sets of signals for sending and receiving: 8-bit data bus MDI0 to MDI7, control signals MISTRT and MIVAL, and MCKL clock signal for time interval.

[0086] The command interface can provide communication between the application program running in the external module (i.e., the conditional access module in the second type card) and the receiving host 10. It includes connecting and removing the module, reading and setting the module status, initializing the module, etc. The module can be composed of an 8-bit bidirectional data bus and address and control signals.

[0087] In the embodiment of the present application, the PCMCIA interface signal definition is divided into three modes: memory only mode, input / output (IO) mode and card bus mode. Among them, the DVB CI card and POD card both use the PCMCIA custom interface mode.

[0088] Memory Only Mode: When the power supply VCC is loaded or the reset (RESET) signal is used to restart the second interface, the slot and the card use the Memory Only interface mode. If the card information structure exists on the card and is successfully parsed, the card and the slot will work as IO interfaces, etc. Otherwise, they will continue to be configured in Memory Only mode.

[0089] IO mode: The IO port must be configured before using the card. During configuration, the IO address, interrupt request and other configurable information are determined by checking the card information structure on the card. Based on the hardware and software compatibility, the system selects the most appropriate configuration on the card through the CIS information.

[0090] CardBus mode: provides high-performance 32-bit bus master functionality for PC Cards.

[0091] In an embodiment of the present application, the custom interface needs to support enhanced features, such as internal bus expansion, or custom signals that are not applicable to cross-architectures. A card or a slot can support multiple custom interfaces. When the card is inserted or the card is powered off, both the slot and the card must use the memory mode interface. After the card is powered on, the system reads the "card information structure" on the card. If it is found that the card supports a custom interface that the host slot also supports, the card and the host slot can be configured to the custom interface mode. The card is configured using the configuration index field of the configuration option register. Both the card information structure and the configuration register are mapped to the attribute memory space of the card.

[0092] For example, in DVB CI interface mode, control signals, data bus, IO and any other 16-bit PC card in memory mode are the same. The main difference is that address signal A[25::14] and data signal D[15::8] are used for transmission of transport stream, thus limiting the public memory space (optional) address range to 16k bytes and the attribute memory space address range to 8k effective bytes (even only 8-bit access).

[0093] For example, in the POD interface mode, it is basically the same as the DVB CI interface mode, except that A[9::4] is used for OOB port data, while in the DVB CI interface mode, A[9::4] is used for the address bus. The same address signal A[25::14] and data signal D[15::8] are used for the transmission of the transport stream, thereby limiting the public memory space (optional) address range to 16k bytes and the attribute memory space address range to 8k effective bytes (even only 8-bit access).

[0094] In the embodiment of the present application, the PCMCIA interface may provide two card detection pins (Card Detect, CD) for detecting the insertion and removal events of the target decryption card. Figure 5 , the second interface P2 may include a first detection pin CD1# and a second detection pin CD2#, and the first detection pin CD1# is correspondingly connected to the third detection pin CD3# of the second type card, and the second detection pin CD2# is correspondingly connected to the fourth detection pin CD4# of the second type card; wherein:

[0095] The interface control module 102 is further configured to determine the insertion status of the second type card according to the first detection signal output by the first detection pin CD1# and the second detection signal output by the second detection pin CD2#.

[0096] It should be noted that, in the embodiment of the present application, on the receiving host side, the interface control module 102 may further include a detection module 501, a first pull-up resistor R1 and a second pull-up resistor R2, wherein:

[0097] The first detection pin CD1# is respectively connected to one end of the first pull-up resistor R1 and the first input end of the detection module 501, and the other end of the first pull-up resistor R1 is connected to the first power supply VCC1;

[0098] The second detection pin CD2# is connected to one end of the second pull-up resistor R2 and the second input end of the detection module 501 respectively, and the other end of the second pull-up resistor R2 is connected to the second power supply VCC2.

[0099] It should also be noted that in the embodiment of the present application, the first input end of the detection module 501 is used to receive the first detection signal output by the first detection pin CD1#, and the second input end of the detection module 501 is used to receive the second detection signal output by the second detection pin CD2#.

[0100] In an embodiment of the present application, the first power supply VCC1 and the second power supply VCC2 may be the same or different. The first power supply VCC1 and the first pull-up resistor R1 are used to pull up the first detection signal output by the first detection pin CD1# to a high level, and the second power supply VCC2 and the second pull-up resistor R2 are used to pull up the second detection signal output by the second detection pin CD2# to a high level. In addition, the resistance values ​​of the first pull-up resistor R1 and the second pull-up resistor R2 can be set according to actual conditions. For example, the resistance values ​​of the first pull-up resistor R1 and the second pull-up resistor R2 can be greater than or equal to 10kΩ.

[0101] It should also be noted that in the embodiments of the present application, Figure 5 As shown, on the target decryption card side, taking the second type card as an example, the second type card may include a third detection pin CD3# and a fourth detection pin CD4#, and the third detection pin CD3# and the fourth detection pin CD4# are grounded; and when the second type card is inserted into the second interface P2, the third detection pin CD3# is correspondingly connected to the first detection pin CD1#, and the fourth detection pin CD4# is correspondingly connected to the second detection pin CD2#.

[0102] In an embodiment of the present application, the interface control module 102 is further used to determine that a second type of card is inserted into the second interface and generate a first interrupt signal when the detection module 501 detects that the first detection signal output by the first detection pin CD1# and the second detection signal output by the second detection pin CD2# are both in a first level state, and the first interrupt signal is used to report an insertion event of the second type of card; or, the interface control module 102 is further used to determine that the second type of card is not inserted into the second interface and generate a second interrupt signal when the detection module 501 detects that at least one of the first detection signal output by the first detection pin CD1# and the second detection signal output by the second detection pin CD2# is in a second level state, and the second interrupt signal is used to report a removal event of the second type of card.

[0103] In the embodiment of the present application, the first level state can be a low level, and the second level state can be a high level. That is, if the detection module 501 detects that both the first detection signal and the second detection signal are low levels, it is determined that the second type card is inserted into the second interface and a first interrupt signal is generated, and the first interrupt signal is used to report the insertion event of the second type card; or, if the detection module 501 detects that at least one of the first detection signal and the second detection signal is high level, it is determined that the second type card is not inserted into the second interface and a second interrupt signal is generated, and the second interrupt signal is used to report the removal event of the second type card.

[0104] It should be noted that, in the embodiment of the present application, the first detection pin CD1# and the second detection pin CD2# are located on the left and right sides of the second interface P2 (i.e., the card slot) to ensure that the target decryption card can be accurately and firmly inserted into the slot. The receiving host side pulls up the two pins, and the target decryption card side internally grounds the two pins. In this way, only when the receiving host side detects that the two pins simultaneously have a low-level card detection signal, the receiving host side confirms that the target decryption card is correctly inserted.

[0105] It should also be noted that, in the embodiment of the present application, for detecting whether the first type of card is correctly inserted into the first interface P1, or whether the first type of card is removed, the working principle of the corresponding card detection mechanism is similar to the working principle of the second type of card inserted into the second interface P2, and will not be described in detail here.

[0106] It should also be noted that in an embodiment of the present application, the receiving host side can report the insertion and removal events of the target decryption card to the software, such as the central processing unit (CPU), through an interrupt signal, and then the CPU issues some control commands to the receiving host or an external target decryption card.

[0107] In some embodiments, taking the second interface and the second type card as an example, the interface control module 102 is further configured to shut down the power of the second type card and disable the second interface P2 within a preset time period when the second type card is removed.

[0108] For example, when the reported target decryption card is correctly inserted, the receiving host side starts to power on, and then performs a series of card type detection and configuration work. If the card is detected to be unplugged, in order to reduce power consumption, the receiving host side will remove the power supply of the card within a preset time period (e.g., 5ms) and disable the corresponding interface.

[0109] In some embodiments, the second interface P2 may further include a fifth detection pin; accordingly, the second type card may further include a voltage detection pin VS1. The interface control module 102 is further configured to obtain a level state at the fifth detection pin when the second type card is inserted into the second interface P2; and determine whether to adjust the power supply voltage of the second type card according to the level state at the fifth detection pin and the second configuration information of the second type card.

[0110] In the embodiment of the present application, when the second type card is inserted into the second interface P2, the voltage detection pin VS1 is connected to the fifth detection pin in the second interface P2. At this time, the level state at the second detection pin is actually the level state at the voltage detection pin VS1.

[0111] In the embodiment of the present application, if the level state at the fifth detection pin is a low level, it indicates that the operating voltage is 3.3 V; if the level state at the fifth detection pin is a high level, it indicates that the operating voltage is 5 V. Exemplarily, if the operating voltage of the second type card is determined to be 5 V according to the level state at the fifth detection pin, but the second type card can operate in a low voltage mode, for example, the operating voltage can be 3.3 V, then the corresponding power pin can be adjusted to switch the power voltage of the second type card to 3.3 V.

[0112] That is to say, in the embodiment of the present application, when the target decryption card is powered on, the information to be read from the voltage detection pin VS1 can be 3.3V or 5V for setting the initial voltage of the card information structure and card access. The voltage detection pin VS1 is high, indicating that VCC = 5V; the voltage detection pin VS1 is low, indicating that VCC = 3.3V. Then read certain configuration information from the card information structure. If the configuration voltage required in the CIS information is different, a voltage switch is required. Here, in the DVB CI interface mode, the card's operating voltage is 5V; in the POD interface mode, the card's operating voltage is 3.3V.

[0113] In this way, after power-on and reset, the receiving host 10 receives the Ready (RDY) signal from the target decryption card, indicating that the target decryption card is ready to be accessed. The receiving host 10 can obtain relevant information of the card by reading the card information structure in the attribute memory. It determines whether the card is a DVB CI card, a POD card or other types of cards, and then sets the corresponding interface to the correct receiving mode.

[0114] It should also be noted that, in the embodiment of the present application, the receiving host 10 can be set in a system on chip (System on Chip, SOC), that is, a digital TV chip. The digital TV chip can be compatible with conditional access circuits of multiple protocol standards, and one of the conditional access modes can be selected and enabled according to different market needs, thereby being able to meet different market needs and improving the versatility of the digital TV chip.

[0115] In some embodiments, the interface control module further includes a counter, wherein the counter is used to start counting after a communication link is established between the target decryption card and the interface control module, and when the count value reaches a preset value, the interface control module starts to obtain an interface signal corresponding to the target decryption card.

[0116] It should also be noted that in the embodiment of the present application, the preset value is a criterion for judging whether the interface signal is stable. After identifying the type of the target decryption card, the interface signal will switch to the corresponding function. In this process, the direction and value of the interface signal will change, and instability is prone to occur. Based on this, after the communication link is established between the target decryption card and the interface control module in the embodiment of the present application, the interface control module does not immediately obtain the interface signal of the target decryption card, but counts through a counter, and only starts to obtain the corresponding interface signal and put it into use after a period of time. In this way, the metastable phenomenon that may be generated when the digital TV chip and the external target decryption card interact with each other is fully considered, thereby improving the stability of the interface signal.

[0117] In another embodiment of the present application, Figure 6 Schematic diagram of the circuit structure of a conditional access system provided in an embodiment of the present application. Figure 6 As shown, the conditional access system 60 may include a target decryption card 601 and the receiving host 10 as described in the above embodiment, and the target decryption card 601 is connected to the interface control module 102 of the receiving host 10 .

[0118] In the embodiment of the present application, Figure 3 As shown in the receiving host 10, Figure 7 A detailed structural diagram of a conditional access system provided in an embodiment of the present application. Figure 7As shown, in the conditional access system 60, the interface control module 102 of the receiving host 10 may include a first interface P1 and a second interface P2, wherein the first interface P1 is used to insert a first type of target decryption card (i.e., first type card C1), and the second interface P2 is used to insert a second type of target decryption card (i.e., second type card C2).

[0119] In some embodiments, the interface control module 102 is used to set the first configuration information of the interface control module 102 according to the first type card C1 and establish communication between the first type card C1 and the interface control module 102 when it detects that the target decryption card is inserted into the first interface P1 and identifies that the target decryption card is a first type card C1, and sends the authorization information in the transmission stream to the first type card C1; the first type card C1 is used to receive the authorization information in the transmission stream and decrypt the authorization information to obtain the first key, and transmit the first key to the first interface P1; the interface control module 102 is used to receive the first key, descramble the transmission stream according to the first key, and obtain a descrambled transmission stream.

[0120] In the embodiment of the present application, the first type card C1 may include a first smart card, that is, the first type card C1 refers to a decryption card based on smart card technology. Exemplarily, the first type card C1 is applicable to Japan.

[0121] In the embodiment of the present application, if the first interface P1 is inserted into the first type card C1, the first configuration information of the interface control module 102 can be set to match the first type card C1, and communication between the first type card C1 and the interface control module 102 can be established.

[0122] That is to say, in the embodiment of the present application, the first configuration information of the interface control module 102 is set according to the first type card C1, so that the first configuration information of the interface control module 102 matches the first type card C1, thereby establishing communication between the first type card C1 and the interface control module 102; based on the communication between the two, the interface control module 102 can send the authorization information in the transmission stream to the first type card C1 through the first interface P1, and then the first type card C1 decrypts the authorization information, obtains the first key and transmits the first key to the first interface P1; after the interface control module 102 receives the first key, it descrambles the transmission stream according to the first key, thereby obtaining a descrambled transmission stream.

[0123] In some embodiments, the interface control module 102 is used to set the second configuration information of the interface control module 102 according to the second type card C2 and establish communication between the second type card C2 and the interface control module 102 when it detects that the target decryption card is inserted into the second interface P2 and identifies that the target decryption card is a second type card C2, and transmit the transmission stream to the second type card C2; the second type card C2 is used to receive the transmission stream and extract the authorization information in the transmission stream, decrypt the authorization information, obtain the second key, descramble the transmission stream according to the second key, and transmit the descrambled transmission stream to the second interface P2.

[0124] It should be noted that in the embodiment of the present application, the second type card C2 includes at least one of the following: a decryption card based on digital television broadcasting and a decryption card based on a configuration point. Among them, the second type card based on digital television broadcasting can be called a DVB CI card, and the second type card based on a configuration point can be called a POD card.

[0125] For example, for the second type card C2, the DVB CI card is applicable to Europe, and the POD card is applicable to North America.

[0126] In the embodiment of the present application, if the second interface P2 is inserted into the second type card C2, the second configuration information of the interface control module 102 can be set to match the second type card C2, and communication between the second type card C2 and the interface control module 102 can be established.

[0127] That is to say, in the embodiment of the present application, the second configuration information of the interface control module 102 is set according to the second type card C2, so that the second configuration information of the interface control module 102 matches the second type card C2, thereby establishing communication between the second type card C2 and the interface control module 102; based on the communication between the two, the second type card C2 can receive the transmission stream and extract the authorization information in the transmission stream, and then decrypt the authorization information. After obtaining the second key, the transmission stream can be descrambled according to the second key, thereby obtaining a descrambled transmission stream and transmitting the descrambled transmission stream to the second interface P2.

[0128] It should also be noted that in the embodiment of the present application, the authorization information here may include authorization control information (ECM) and authorization management information (EMM), but there is no specific limitation.

[0129] It should also be noted that in the embodiment of the present application, the second type card C2 may only include a conditional access module, but in some cases the conditional access module is also required to be used in conjunction with a smart card. Figure 7The second type card C2 may include a conditional access module 701 and a second smart card C3, and the conditional access module 701 includes a third interface, and the third interface is used to insert the second smart card C3.

[0130] The conditional access module 701 is used to receive the transmission stream and extract the authorization information in the transmission stream, and send the authorization information in the transmission stream to the second smart card C3;

[0131] The second smart card C3 is used to receive the authorization information in the transmission stream and decrypt the authorization information to obtain a second key, and transmit the second key to the conditional access module 701;

[0132] The conditional access module 701 is further configured to receive a second key, descramble the transport stream according to the second key, and transmit the descrambled transport stream to the second interface P2.

[0133] In the embodiment of the present application, the interface control module 102 is connected to the conditional access module 701 via the second interface P2. Here, the processing of the entitlement control information (ECM) and entitlement management information (EMM) in the conditional access technology is directly integrated into an external module (i.e., the "conditional access module"), so that the machine and card can be separated, making the functions of the digital television tend to be universal.

[0134] It should be noted that, in the embodiment of the present application, if it is detected that the first interface P1 is inserted into the target decryption card, the target decryption card can be identified as the first type card C1; if it is detected that the second interface P2 is inserted into the target decryption card, the target decryption card can be identified as the second type card C2. Specifically, after the card is powered on, the card information structure of the target decryption card is obtained, and then the type of the target decryption card can be determined according to the card information structure. Exemplarily, for the second type card C2, it can also be determined according to the card information structure whether the target decryption card is a DVB CI card or a POD card. In this way, the most appropriate configuration information can be selected for the interface control module 102 according to the card information structure.

[0135] It should also be noted that, in the embodiment of the present application, there is a matching standard interface between the receiving host 10 and the target decryption card 601, so that the target decryption card 601 can be connected to the receiving host 10 to achieve an electrical connection between the target decryption card 601 and the receiving host 10, and a gold finger method can be used here, such as an interface of the PCMCIA standard, or an interface such as USB can also be used. Exemplarily, the second interface P2 can be an interface using the PCMCIA standard, which can be referred to as a "PCMCIA interface" for short.

[0136] In some embodiments, the conditional access module 701 is further configured to encrypt the descrambled transport stream when the descrambled transport stream complies with a preset interface protocol, and transmit the encrypted descrambled transport stream to the second interface P2.

[0137] In the embodiment of the present application, the preset interface protocol may be the CIPlus protocol specification. That is, if the transmission stream complies with the CIPlus protocol, the transmission stream may also be encrypted, and then the encrypted transmission stream may be securely transmitted to the receiving host 10 through the second interface P2. Exemplarily, the "encryption process" may be the CC encryption process, and correspondingly, the "decryption process" may be the CC decryption process.

[0138] That is to say, after the demultiplexing processing by the demultiplexing module 1031, the content decryption module 1032 can determine whether the demultiplexed transmission stream has been subjected to CC encryption processing. If CC encryption processing has been performed, then the demultiplexed transmission stream needs to be subjected to CC decryption processing to output the audio stream and video stream to be played; otherwise, if CC encryption processing has not been performed, then the transmission stream can be directly output, that is, clear audio stream and video stream can be obtained.

[0139] The embodiment of the present application provides a conditional access system, which can be compatible with various types of decryption cards through an interface control module in a receiving host, thereby meeting market demands in different regions and improving the versatility of digital television chips; and adopts a machine-card separation method to integrate part of the circuits used for descrambling processing in an external decryption card, which can also make the digital television functions tend to be universal, and also fully considers the metastable phenomenon that may be generated when the receiving host and the external decryption card perform data interaction, thereby improving stability; in this way, the universality of digital television can be improved while reducing costs, which is conducive to the development of digital television.

[0140] In another embodiment of the present application, the embodiment of the present application further provides a digital television, which may include a target decryption card 601 and a receiving host 10 as described in the above embodiment, and the target decryption card 601 is connected to the interface control module 102 of the receiving host 10.

[0141] In the embodiment of the present application, there is a matching standard interface between the receiving host 10 and the target decryption card 601, so that the target decryption card 601 can be connected to the receiving host 10 to achieve an electrical connection between the target decryption card 601 and the receiving host 10. The standard interface can adopt a gold finger method, such as a PCMCIA interface, or can also adopt an interface such as USB.

[0142] Here, a card slot matching the shell of the target decryption card 601 may be provided on the casing of the receiving host 10. For example, the target decryption card 601 may be made into a rectangular shape with one end adapted to the above-mentioned interface, and then an inner concave card slot matching the rectangular shape may be provided on the casing of the receiving host 10, so that the target decryption card 601 can be inserted into the above-mentioned first interface / second interface through the card slot.

[0143] In yet another embodiment of the present application, based on the aforementioned conditional access system 60, Figure 8 The following is a flow chart of a method for operating a digital television provided in an embodiment of the present application. Figure 8 As shown, the method includes:

[0144] S801, receiving a high-frequency digital television signal, tuning and demodulating the high-frequency digital television signal, generating a transport stream and transmitting the transport stream to an interface control module.

[0145] Here, tuning and demodulating the high-frequency digital TV signal, generating a transmission stream and transmitting it to the interface control module may include: receiving the high-frequency digital TV signal through the tuning module and converting the high-frequency digital TV signal into an intermediate-frequency digital TV signal; receiving the intermediate-frequency digital TV signal through the demodulation module, demodulating the intermediate-frequency digital TV signal, generating a transmission stream and transmitting it to the interface control module.

[0146] S802, when the interface control module detects that the target decryption card is inserted, it identifies the type of the target decryption card, sets configuration information of the interface control module according to the type of the target decryption card, and establishes communication between the target decryption card and the interface control module.

[0147] Here, identifying the type of the target decryption card may include: determining that the target decryption card is a first type card when detecting that the target decryption card is inserted into the first interface of the interface control module; and determining that the target decryption card is a second type card when detecting that the target decryption card is inserted into the second interface of the interface control module.

[0148] In some embodiments, identifying the type of the target decryption card may further include: acquiring a card information structure of the target decryption card; and determining the type of the target decryption card according to the card information structure.

[0149] In the embodiment of the present application, after the card is powered on, the card information structure of the target decryption card is obtained, and then the type of the target decryption card can be determined according to the card information structure. Exemplarily, it can be determined whether the target decryption card is a DVB CI card or a POD card according to the card information structure, so that the most suitable configuration information can be selected for the interface control module 102 according to the card information structure.

[0150] S803, descrambling the transport stream based on the target decryption card to obtain a descrambled transport stream, and transmitting the descrambled transport stream to the interface control module.

[0151] In an embodiment of the present application, if the target decryption card is a first type of card, then descrambling the transmission stream based on the target decryption card to obtain a descrambled transmission stream may include: when the interface control module detects that the target decryption card is inserted into the first interface and identifies that the target decryption card is a first type of card, setting the first configuration information of the interface control module according to the first type of card and establishing communication between the first type of card and the interface control module, and sending the authorization information in the transmission stream to the first type of card; receiving the authorization information in the transmission stream through the first type of card and decrypting the authorization information to obtain a first key, and transmitting the first key to the first interface; and then receiving the first key through the interface control module, descrambling the transmission stream according to the first key to obtain a descrambled transmission stream.

[0152] In an embodiment of the present application, if the target decryption card is a second type card, then descrambling the transmission stream based on the target decryption card to obtain a descrambled transmission stream may include: when the interface control module detects that the target decryption card is inserted into the second interface and identifies that the target decryption card is the second type card, setting the second configuration information of the interface control module according to the second type card and establishing communication between the second type card and the interface control module, and transmitting the transmission stream to the second type card; receiving the transmission stream through the second type card and extracting authorization information in the transmission stream, decrypting the authorization information to obtain a second key, descrambling the transmission stream according to the second key, and transmitting the descrambled transmission stream to the second interface.

[0153] It should be noted that, in the embodiment of the present application, the first type of card may refer to a first smart card, which is applicable to Japan. The second type of card may be a decryption card based on digital television broadcasting (referred to as a "DVB CI card") or a decryption card based on a configuration point (referred to as a "POD card"). Among them, the DVB CI card is applicable to Europe, and the POD card is applicable to North America.

[0154] In a specific implementation, in addition to the conditional access module, the second type of card may also include a second smart card, and the second smart card is connected to the conditional access module. The conditional access module may receive the transmission stream and extract the authorization information in the transmission stream, and send the authorization information in the transmission stream to the second smart card; the second smart card may receive the authorization information in the transmission stream and decrypt the authorization information to obtain the second key, and transmit the second key to the conditional access module; after the conditional access module receives the second key, the transmission stream may be descrambled according to the second key, and the descrambled transmission stream may be transmitted to the second interface, so that the receiving host can obtain the descrambled transmission stream.

[0155] S804: Decode the descrambled transport stream and output the audio stream and video stream to be played.

[0156] Here, decoding the descrambled transport stream and outputting the audio stream and video stream to be played may include: receiving the descrambled transport stream sent by the interface control module through the demultiplexing module, demultiplexing the descrambled transport stream, and generating a demultiplexed transport stream; receiving the demultiplexed transport stream through the content decryption module (i.e., CC decryption module), and when it is determined that the demultiplexed transport stream has CC encryption, performing CC decryption on the demultiplexed transport stream, and outputting the audio stream and video stream to be played.

[0157] In the embodiment of the present application, the method may further include: playing the obtained audio stream through an audio playback module; and displaying the obtained video stream through a video display module.

[0158] Here, the audio playback module can be implemented by an amplifier circuit and a speaker. The video display module can be implemented by a driver module and a display screen. For example, the driver module can be an LVDS module, and the display screen can be an LCD screen. The LVDS module drives the LCD screen to display the video stream.

[0159] The embodiment of the present application provides an operating method of a digital television, in which, through an interface control module in a receiving host, various types of decryption cards can be compatible, thereby meeting market demands in different regions and improving the versatility of digital television chips; and by adopting a machine-card separation method, part of the circuit for descrambling processing is integrated in an external decryption card, which can also make the digital television function more universal, and also fully consider the metastable phenomenon that may be generated when the receiving host and the external decryption card perform data interaction, thereby improving stability; in this way, the universality of digital television can be improved while reducing costs, which is conducive to the development of digital television.

[0160] In yet another embodiment of the present application, based on the above embodiment Figure 7 The conditional access system shown in the figure has the following modules: tuning module, demodulation module, demultiplexing module, CC decryption module, and interface control module supporting three decryption cards: DVB CI, POD and Smart Card. According to different reception requirements, a suitable conditional access solution can be selected.

[0161] The tuning module (Tuner) is also called a high-frequency head. In digital television, signals of different TV programs use different carrier frequency bands. The tuner amplifies and mixes the carrier signal at high frequency to make the carrier signal differ from the current frame signal, thereby converting the RF carrier signal into an intermediate frequency carrier signal.

[0162] The demodulation module (Demod) contains multiple modulation and demodulation IPs and ADCs, which can provide demodulation of different standards and output TS streams. The ADC can support high-speed analog-to-digital conversion with low latency.

[0163] Among them, in the interface control module, for the insertion of the second type of card (DVB CI / POD card), the demodulated TS stream can be sent to the external DVB CI / POD card (commonly known as the big card) through the second interface (i.e. Common Interface). The big card extracts the ECM and EMM packets from the TS stream sent by the host side and sends them to the smart card authorized by the CA manufacturer. The smart card parses the key of the current TV program and then sends it to the big card for program descrambling. If the descrambled TS stream meets the CIPlus protocol specification, it will also be encrypted by CC and then transmitted to the host. For the insertion of the second type of card (Smart Card), the interface control module is used to communicate with the smart card. The host gives the smart card the required CA information, and the smart card parses the corresponding key.

[0164] In addition, the demultiplexing module (Demux) is used to provide MPEG-2TS stream demultiplexing and recording functions for digital TV. The CC decryption module (CC Decryption) is used to determine whether the TS stream has been CC encrypted. If it has been CC encrypted, CC decryption is performed; otherwise, it is directly output to obtain clear audio and video streams.

[0165] In the embodiment of the present application, both the DVB CI card and the POD card use the PCMCIA interface (Personal Computer Memory Card International Association, referred to as PC card), and the circuit structure is as follows: Figure 4 As shown in the figure, two interfaces are defined here: one is the MPEG-2TS stream interface and the other is the command interface.

[0166] The TS stream interface supports bidirectional MPEG-2 data stream transmission between the host and the decryption card. The demodulated data is transmitted to the decryption card through the TS stream interface for descrambling, and then the decryption card transmits the CA descrambled code stream back to the host through the TS stream interface; the TS stream interface can include two sets of signals for sending and receiving: 8-bit data bus MDI0 to MDI7, control signals MISTRT and MIVAL, and MCKL clock signal for time interval.

[0167] The command interface provides external conditional access to the communication between the application program running on the module and the host resources. It includes connecting and removing the module, reading and setting the module status, initializing the module, etc. The module consists of an 8-bit bidirectional data bus and address and control signals.

[0168] The PCMCIA interface signal definition is divided into three modes: memory only mode, input / output (IO) mode, and card bus (CardBus mode). Among them, DVB CI card and POD card use the PCMCIA custom interface mode.

[0169] Memory Only Mode: When the power supply VCC is loaded or the interface is restarted using the RESET signal, the slot and card use the Memory Only interface mode. If the card information structure exists on the card and is successfully parsed, the card and slot will work as IO interfaces, etc. Otherwise, they will continue to be configured in Memory Only mode.

[0170] IO mode: The IO port must be configured before use. During configuration, the IO address, interrupt request and other configurable information are determined by checking the card information structure on the card. Based on the hardware and software compatibility, the system selects the most appropriate configuration on the card through CIS information.

[0171] CardBus mode: can provide high-performance 32-bit bus master function for PC Card.

[0172] In addition, the custom interface needs to support enhanced features, such as internal bus expansion, or custom signals that are not applicable across architectures. A card or a slot (or "socket") can support multiple custom interfaces. Both the slot and the card must use the memory mode interface when the card is inserted or powered off. After the card is powered on, the system reads the "card information structure" of the card. If it is found that the card supports a custom interface that the host slot also supports, the card and the host slot can be configured to custom interface mode. The card is configured using the configuration index field of the configuration option register. Both the CIS and the configuration registers are mapped into the attribute memory space of the card.

[0173] In DVB CI interface mode, the control signals and data bus are the same as any other 16-bit PC card in I / O and memory mode. The main difference is that the address signal A[25::14] and the data signal D[15::8] are used for TS stream transmission, thus limiting the public memory space (optional) address range to 16k bytes and the attribute memory space address range to 8k effective bytes (even only 8-bit access).

[0174] In POD interface mode, it is basically the same as DVB CI interface mode, except that A[9::4] is used for OOB port data. The same address signal A[25::14] and data signal D[15::8] are used for TS stream transmission, thus limiting the public memory space (optional) address range to 16k bytes and the attribute memory space address range to 8k effective bytes (even only 8-bit access).

[0175] The PCMCIA interface provides two card detection pins for detecting the insertion and removal of PC cards. These two pins are located on the left and right sides of the card slot to ensure that the card can be inserted into the slot accurately and firmly. The host side pulls up the level of these two pins, and the PC card side internally grounds the two pins; only when the host side detects that the card detection signal appears on both pins at the same time (and both pins are low), the host side considers that the card is correctly inserted. The card detection mechanism is as follows Figure 5 As shown. The resistance values ​​of the two pull-up resistors are set according to actual conditions. Exemplarily, the resistance value of the pull-up resistor can be greater than or equal to 10 kΩ.

[0176] Furthermore, the host side reports the card insertion and removal events to the software through interrupt signals. When the card is correctly inserted, the host is powered on and then performs a series of card type detection and configuration tasks. If the card is detected to be pulled out, the host will remove the power supply of the card within 5ms and disable the corresponding interface.

[0177] In addition, when the card is powered on, the information that needs to be read from the voltage detection pin VS1 on the card can set the initial voltage for CIS and card access to 3.3V or 5V. The voltage detection pin VS1 is high, indicating that the working voltage is 5V; the voltage detection pin VS1 is low, indicating that the working voltage is 3.3V. Then read certain configuration information from the card information structure CIS. If the configuration voltage required in the information is different, a voltage switch is required. For example, in CI interface mode, the working voltage of the card is 5V; in POD interface mode, the working voltage of the card is 3.3V.

[0178] In this way, after power-on and reset, the host receives the ready signal (RDY signal) sent by the card, indicating that the card is ready to be accessed. The host obtains the card information by reading the attribute memory CIS. It determines whether the card is a DVB CI card, a POD card or other types of cards, and then sets the interface to the correct receiving mode. In this way, a universal conditional receiving module design is realized, which can adapt to a variety of conditional receiving modes.

[0179] In the embodiment of the present application, the specific implementation of the aforementioned embodiment is elaborated in detail through the above embodiment. It can be seen that through the technical solution of the aforementioned embodiment, in order to meet different market demands, a conditional access system compatible with multiple protocols is designed here, which can support conditional access modes of multiple specifications; according to the different needs of the market, one of the conditional access schemes is selected and enabled to meet different market requirements and improve the versatility of the digital TV chip. Moreover, through the machine-card separation method, the processing of the core parts such as the authorization control information and the authorization management information in the conditional access technology is directly integrated into an external conditional access module, so that the functions of the digital TV tend to be universal. In addition, when designing the conditional access system, the metastable phenomenon that may be generated when the digital TV chip and the external card interact with each other is fully considered to improve the stability. In this way, the universality of digital TV can be improved while reducing costs, which is conducive to the development of digital TV.

[0180] In the embodiment of the present application, a computer-readable storage medium is also provided for storing a computer program. The computer-readable storage medium can be applied to the digital television in the embodiment of the present application, and when the computer program is executed by at least one processor, the corresponding process implemented by the digital television in each method of the embodiment of the present application is implemented, which will not be described in detail for the sake of brevity.

[0181] In the embodiment of the present application, a computer program product is also provided, including computer program instructions. The computer program product can be applied to the digital television in the embodiment of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the digital television in each method of the embodiment of the present application, which will not be described in detail for the sake of brevity.

[0182] Those of ordinary skill in the art will appreciate that the devices, systems, and algorithm steps of each example described in conjunction with the embodiments disclosed in this application can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0183] It should also be understood by those skilled in the art that the devices, systems and methods disclosed in the present application can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0184] It should also be noted that in this application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0185] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0186] The features disclosed in several product embodiments provided in this application can be arbitrarily combined without conflict to obtain new product embodiments.

[0187] The features disclosed in several system or method embodiments provided in this application can be arbitrarily combined without conflict to obtain new system embodiments or method embodiments.

[0188] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A receiving host, characterized in that: The receiving host comprises a front-end processing module, an interface control module and a back-end processing module, wherein: The front-end processing module is used to receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transmission stream and transmit it to the interface control module; The interface control module is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module according to the type of the target decryption card, and establish communication between the target decryption card and the interface control module, so that the target decryption card performs descrambling processing on the transmission stream, and transmits the obtained descrambled transmission stream to the interface control module; The back-end processing module is used to decode the descrambled transport stream and output the audio stream and video stream to be played.

2. The receiving host according to claim 1, characterized in that: The interface control module includes a first interface, wherein: The interface control module is configured to, when detecting that the target decryption card is inserted into the first interface and identifying that the target decryption card is a first type card, set the first configuration information of the interface control module according to the first type card and establish communication between the first type card and the interface control module, so that the first type card performs descrambling processing on the transmission stream and transmits the obtained descrambled transmission stream to the interface control module; The first type of card includes: a first smart card.

3. The receiving host according to claim 1, characterized in that: The interface control module also includes a second interface, wherein: The interface control module is configured to, when detecting that the target decryption card is inserted into the second interface and identifying that the target decryption card is a second-type card, set the second configuration information of the interface control module according to the second-type card and establish communication between the second-type card and the interface control module, so that the second-type card performs descrambling processing on the transmission stream and transmits the obtained descrambled transmission stream to the interface control module; The second type of card includes at least one of the following: a decryption card based on digital television broadcasting and a decryption card based on a configuration point.

4. The receiving host according to claim 3, characterized in that: The second interface includes a first detection pin and a second detection pin, and the first detection pin is connected to the third detection pin of the second type card correspondingly, and the second detection pin is connected to the fourth detection pin of the second type card correspondingly; The interface control module is further used to determine the insertion status of the second type card according to the first detection signal output by the first detection pin and the second detection signal output by the second detection pin.

5. The receiving host according to claim 4, characterized in that: The second interface further includes a fifth detection pin, wherein: The interface control module is further used to obtain the level state of the fifth detection pin when the second type card is inserted into the second interface; and determine whether to adjust the power supply voltage of the second type card according to the level state of the fifth detection pin and the second configuration information of the second type card; Wherein, the second type card further includes a voltage detection pin, and when the second type card is inserted into the second interface, the voltage detection pin is correspondingly connected to the fifth detection pin.

6. The receiving host according to any one of claims 1 to 5, characterized in that: The back-end processing module includes a demultiplexing module and a content decryption module, wherein: The demultiplexing module is used to receive the descrambled transport stream sent by the interface control module, perform demultiplexing processing on the descrambled transport stream, and generate a demultiplexed transport stream; The content decryption module is used to receive the demultiplexed transport stream, and when it is determined that the demultiplexed transport stream has been encrypted, decrypt the demultiplexed transport stream and output the audio stream and video stream to be played.

7. A conditional access system, characterized in that: The conditional access system comprises a target decryption card and a receiving host, and the target decryption card is connected to an interface control module of the receiving host; The receiving host comprises a front-end processing module, an interface control module and a back-end processing module, wherein: The front-end processing module is used to receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transmission stream and transmit it to the interface control module; The interface control module is used to identify the type of the target decryption card when detecting that the target decryption card is inserted, set the configuration information of the interface control module according to the type of the target decryption card, and establish communication between the target decryption card and the interface control module, so that the target decryption card performs descrambling processing on the transmission stream, and transmits the obtained descrambled transmission stream to the interface control module; The back-end processing module is used to decode the descrambled transport stream and output the audio stream and video stream to be played.

8. The conditional access system according to claim 7, characterized in that: The receiving host comprises a first interface, wherein the first interface is used to insert the target decryption card, wherein: The interface control module is configured to, when detecting that the target decryption card is inserted into the first interface and identifying that the target decryption card is a first type of card, set the first configuration information of the interface control module according to the first type of card and establish communication between the first type of card and the interface control module, and send the authorization information in the transmission stream to the first type of card; The first type card is used to receive the authorization information in the transmission stream and decrypt the authorization information to obtain a first key, and transmit the first key to the first interface; The interface control module is configured to receive the first key, and perform descrambling processing on the transport stream according to the first key to obtain the descrambled transport stream; The first type of card includes: a first smart card.

9. The conditional access system according to claim 8, characterized in that: The receiving host further comprises a second interface, wherein the second interface is used to insert the target decryption card, wherein: The interface control module is configured to, when detecting that the target decryption card is inserted into the second interface and identifying that the target decryption card is a second type card, set the second configuration information of the interface control module according to the second type card and establish communication between the second type card and the interface control module, and transmit the transmission stream to the second type card; The second type card is used to receive the transport stream and extract the authorization information in the transport stream, decrypt the authorization information to obtain a second key, descramble the transport stream according to the second key, and transmit the descrambled transport stream to the second interface; The second type of card includes at least one of the following: a decryption card based on digital television broadcasting and a decryption card based on a configuration point.

10. The conditional access system according to claim 9, characterized in that: The second type card comprises a conditional access module and a second smart card, and the conditional access module comprises a third interface, and the third interface is used to insert the second smart card, wherein: The conditional access module is used to receive the transmission stream and extract the authorization information in the transmission stream, and send the authorization information in the transmission stream to the second smart card; The second smart card is used to receive the authorization information in the transmission stream and decrypt the authorization information to obtain a second key, and transmit the second key to the conditional access module; The conditional access module is further configured to receive the second key, descramble the transport stream according to the second key, and transmit the descrambled transport stream to the second interface.

11. The conditional access system according to claim 10, characterized in that: The conditional access module is further configured to encrypt the descrambled transport stream when the descrambled transport stream complies with a preset interface protocol, and transmit the encrypted descrambled transport stream to the second interface.

12. A digital television, characterized in that: The digital television comprises a target decryption card and a receiving host as claimed in any one of claims 1 to 6, and the target decryption card is connected to an interface control module of the receiving host.

13. A method for operating a digital television, characterized in that: The method comprises: Receive high-frequency digital television signals, tune and demodulate the high-frequency digital television signals, generate a transmission stream and transmit it to the interface control module; When the interface control module detects that a target decryption card is inserted, it identifies the type of the target decryption card, sets configuration information of the interface control module according to the type of the target decryption card, and establishes communication between the target decryption card and the interface control module; Descrambling the transport stream based on the target decryption card to obtain a descrambled transport stream, and transmitting the descrambled transport stream to the interface control module; The descrambled transport stream is decoded and an audio stream and a video stream to be played are output.

Images