CN100454964C - A method for loading a network interface module of a digital TV set-top box - Google Patents

Abstract

The invention relates to a loading method of a digital TV set-top box network interface module, comprising: defining a unified NIM chip driver interface, a unified NIM property structure and a unified frequency point information structure; NIM module driver identification and NIM module driver loading. The present invention has good adaptability to network interface modules of different types and models, can support the access of various network interface modules, and can replace the hardware of the network interface module through power-off and plugging without changing the software, similar to plug and play Use the effect. The invention enables the software and hardware platform system to well support diversified requirements, saves costs, and improves stability at the same time.

Description

A method for loading a network interface module of a digital TV set-top box

technical field

The invention belongs to the field of broadcast communication, in particular, the invention relates to a loading method of a network interface module of a digital TV set-top box.

Background technique

Digital Video Broadcasting (DVB) is a set of protocols developed by the European Telecommunications Standards Committee for the transmission of digital television, digital audio and data. In the DVB application environment, the DVB service provider broadcasts digital video, audio and data streams in DVB format to users at the other end through the communication network. The client receives the front-end broadcast programs through the decoding device, which is the receiver set top box (STB).

The NIM (Network Interface Module) network interface module is the interface between the receiver set-top box and the external network. It has three main functions: 1. Realize communication with the main chip, interpret and execute the control commands of the main chip. 2. Realize the functions of the data link layer. 3. Realize the physical layer function and establish a communication connection with the external network. The digital TV network interface module down-converts the received signal to an intermediate frequency, performs channel decoding and some basic error correction, and then converts it into a TS code stream and sends it to the main chip of the terminal.

The current DVB standard stipulates that there are mainly three different signal transmission methods:

DVB-S refers to the Satellite mode, and the signal is transmitted through the satellite channel;

DVB-C refers to the Cable mode, which transmits signals through coaxial cables;

DVB-T refers to the Terrestrial method, which means that it is transmitted by terrestrial broadcasting, and the signal is transmitted through terrestrial radio waves.

So there are three different types of NIM modules, which are used to receive these three different signals. In addition, because there are many manufacturers producing NIM module main chips, there are many different types of NIM main chips and reference modules in the same transmission mode. Existing set-top box solutions can only use a specific type of NIM main chip. If other chips need to be used, both hardware and software need to be changed.

Contents of the invention

The purpose of the present invention is to provide a method for realizing a universal network interface, so that the terminal body of the same digital TV set-top box can automatically identify different NIM modules, thereby automatically becoming a receiver of corresponding signals.

In order to achieve the above-mentioned purpose of the invention, the present invention provides a digital TV set-top box network interface module loading method, including:

1) Define a unified network interface module (NIM) chip driver interface, a unified network interface module property structure and a unified frequency point information structure;

The unified network interface module chip driver interface is to define the chip driver interface as a group of driver functions corresponding to a series of I2C operations;

The defined unified network interface module property structure is to define all properties of the network interface module in a network interface module structure, which includes: signal transmission mode type, I2C address, reserved flag bits, and a series of functions pointer; each function pointer points to a driver function;

The frequency point information structure with a unified definition is to use three different types of frequency point information of DVB-S, DVB-C, and DVB-T as members of a community structure, and distinguish them by system identification numbers;

2) Carry out drive identification to the network interface module, detect different I2C address response signals, and obtain the system identification number of the current network interface module;

3) According to the system identification number obtained in step 2), the network interface module is driven and loaded, and the driver loading process includes: according to different system identification numbers, the system assigns different values to the members of the network interface module structure and corresponds to The driver functions of different I2C operations correspond to a series of pointers one by one.

The network interface module driver identification is a process of detecting different I2C address response signals, including the following steps:

21) Discovering the network interface module: by trying to communicate with all possible I2C addresses in the list one by one, and monitoring the response, it is found whether the system is connected to the corresponding network interface module;

22) Determine the model of the network interface module; first, preliminarily determine the model of the channel demodulation chip, send the corresponding command to read the id of the channel demodulation chip; if the id is correct, the chip model can be finally confirmed, if the corresponding id cannot be read, that is Confirm that step 21) is wrong, and return to step 21); after judging the signal of the channel demodulation chip, further judge the tuning chip, and after obtaining the tuning chip id, you can use the models of the two chips and the network interface module and chip The corresponding list of models determines the model of the current network interface module;

23) Generate a corresponding system identification number according to the model of the network interface module, the manufacturer code in the system at that time, and the system performance description table; after obtaining the system identification number, you can enter step 3).

The loading of the network interface module driver is a process of assigning values to the structure of the network interface module.

The loading method of the digital TV set-top box network interface module provided by the present invention also includes unifying the hardware interface of different network interface modules and the main board, the hardware interface adopts a 34-pin double-row pin interface, and the interface includes a network interface module power supply interface, a TS stream interface and control response interface lines.

Advantages of the present invention:

Since the present invention has good adaptability to network interface modules of different types and models, it can support the access of various network interface modules, and the hardware of the network interface module can be replaced by plugging and unplugging without changing the software, similar to plug-and-play Ready-to-use effects. In the traditional digital TV receiver set-top box solution, the interface implementation method is generally only applicable to a specific type of network interface module, which is highly dependent on hardware. Once there is a need to replace the network interface module, hardware and software must be carried out for a long time. Major changes will seriously affect the stability of the entire system and greatly lengthen the development cycle. However, the loading method of the network interface module of the digital TV set-top box of the present invention enables the software and hardware platform system to well support diversified requirements, saves costs, and improves stability at the same time.

Description of drawings

Figure 1 is a schematic diagram of the NIM module hardware architecture and interfaces;

Fig. 2 is a digital television receiver system software structure diagram;

Fig. 3 is the detection and judgment flowchart of NIM module among the present invention;

Fig. 4 is a schematic diagram of the hardware interface between the main system part of the receiving terminal and the network interface module in the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

The solution of the present invention adopts the method of integrating multiple NIM drivers in the software, as shown in FIG. 2 . It should be noted that although these NIM drivers seem to exist side by side in the program, only one driver may be loaded and executed during the actual program running, so it does not affect the execution efficiency, but only occupies more storage space.

In order to facilitate loading of the driver, the software part of the present invention needs to define a unified NIM chip driver interface, a unified NIM property structure, and a unified frequency point information structure.

First, a unified chip driver interface.

The chip driver is mainly provided by the manufacturer of the network interface chip. Chip drivers have the characteristics of diversity. However, regardless of the specific form, they have the same basic structure in essence, and they all control the actions of the hardware by reading and writing related registers. The reading and writing of registers is often carried out through the I2C bus. Therefore, the chip driver can essentially be regarded as a combination of a series of I2C operations. In the system solution of this embodiment, the drive interface of the chip is formally unified into a set of functions in Table 1:

Table 1

Signal_connect Connect to the corresponding frequency point Send_diseqc10 Send diseqc1.0 signal Send_diseqc12 Send diseqc1.2 signal Auto_scan   Full Band Search Check_lock_state Detect module lock status Get_signal_strength read signal strength Get_signal_quality read signal quality Get_signal_freq Read the center frequency of the current frequency point Detect Confirm the chip model in the network interface module and reset Initialize Initialize the channel demodulation chip and tuning chip Monitor_callback Monitoring callback function

These functions all point to empty functions when powered on, and register one by one when loading.

Second, the unified NIM property structure.

In the system of this embodiment, all properties of the network interface module are included in a structure, and this structure is named NIM. The structure members include: signal transmission type, I2C address, reserved flag bits, and a series of function pointers. Each pointer points to a driver function. In the program above the chip driver layer, the NIM structure is called to complete the operation, and the underlying driver function cannot be seen. In this way, the members of the structure can be used to represent the corresponding functions during the program writing process, but they are linked to different underlying driver functions for execution during actual execution.

3. Unified frequency point information structure

There is also a big difference in the software part of different types of NIM modules in that the frequency point information structure is different. For example, the frequency point information of satellite frequency points and the frequency point information of terrestrial broadcasting are very different. In order to solve this problem, this system regards three different types of frequency point information as members of a community structure, and uses the system identification number to confirm which frequency point information structure is used in a specific operation process. When stored in Flash, the structure of sequential linked list is adopted. This area can be shared by different types of NIMs: different types of frequency point information data can be stored in the same memory segment, but only one type of information will take effect after each program is powered on and running again. In this way, as long as you know the starting position of the table header, the size of different frequency point information structures, and the relative position number of the required frequency point information, you can find it smoothly.

The following specifically introduces the identification and loading process of the driver of this embodiment:

Driver identification: First of all, it needs to be explained that the I2C addresses of different chips from different manufacturers are always different. Based on this characteristic, the system understands the model information of the product so as to identify the model information of different NIMs. The identification process of the network interface module is the process of detecting the response signals of different I2C addresses, which can also be called the detection and judgment of the NIM module. Refer to Figure 3. There are several steps as follows: The first step is to find out, here, all possible I2C addresses in the list are tried to communicate one by one, and the response is monitored, so as to find out whether the system is connected to the corresponding network interface module. It should be noted that there are often two chips in the network interface module. Generally, it is judged according to the address of the channel demodulator. The second step is to determine the chip model. If a certain I2C address responds through the first step, you can preliminarily determine the model of the channel demodulator. At this time, you need to send related commands to read the id of the channel demodulator chip. Only when the correct ID is read can the chip model be finally confirmed. If the corresponding id cannot be read at this time, it is confirmed that the first step is wrong, and it is necessary to return to the first step. After determining the model of the channel demodulation chip, it is necessary to further determine the tuning chip. After obtaining the tuner chip id, it can be determined which model the current module is based on the models of the two chips and the corresponding list of network interface modules and chip models. The third step is to generate a corresponding system identification number according to the model of the network interface module, the manufacturer code in the system at that time, and the system performance description table.

After obtaining the system identification number, the driver of the NIM module can be loaded.

Loading of the driver module: The loading process of the NIM module driver is the process of assigning the value of the NIM structure. The main content of the process is: according to different system identification numbers, the system assigns different values to the members of the NIM structure and uses different operation functions One-to-one correspondence with this series of pointers can also be called function registration. It should be noted that the system identification number will not only affect the loading of the NIM module driver, but also affect the loading of the menu, so that different styles of menus can be presented.

Each time the receiving terminal using this embodiment is powered on, it will perform NIM identification, confirm the data structure type of this operation and load a suitable driver. The main body of the receiver can replace the NIM board at any time, and the hardware and software of the main part do not need to be changed, which is similar to the plug-and-play effect. However, these small NIM boards are limited to those whose drivers have been added to the system software in advance. If the NIM driver has not been compiled into the software, the terminal will not be able to recognize it. In this case, the system will give a prompt, declaring that the operation failed and failed to find a suitable NIM module.

The invention also includes a method for realizing the hardware interface.

From the schematic diagram of the system hardware (see Figure 1), it can be seen that the hardware interface of the main system part of the receiving terminal and the network interface module mainly includes three parts:

The first part is the power supply interface. The network interface module is a high-frequency analog-digital hybrid device, so the requirements for the accuracy and stability of the power supply voltage are relatively strict. Some satellite receiving and terrestrial broadcast receiving terminals also need to supply power to the antenna through the network interface module. In order to ensure safety and reliability, the power supply interface of the network interface module needs to have voltage control and overload protection functions.

The second part is the TS stream bus. The original TS stream recovered from the RF signal is sent to the back-end source decoder and other devices through this bus. This bus, on various network interface module devices, is basically designed according to the DVB/MPEGII TS stream interface label (EN50083-9) of CATV/SMATV network interface modules similar to professional equipment, including bit clock, data, data valid, TS Signals such as stream packet synchronization can be transmitted in parallel or serial.

The third part is the control response interface, which is convenient for the main CPU to monitor the working status of the network interface module. Most network interface module devices use the IIC bus as the control response interface. The main CPU can send operation instructions to the network interface module through this interface, and can also obtain the main status information of the network interface module through this interface, such as signal lock, lock loss and so on.

In this embodiment, these three types of interfaces are uniformly specified in 34 pin header interfaces, and these pin header interfaces also have reserved interfaces for individual definition and use of specific models of NIM chips. The schematic diagram of the pin definition of the 34-pin socket is shown in Figure 4. The interface signal definition is shown in Table 2:

Table 2

Claims (3)

1, a kind of digital TV set top box network interface module loading method is characterized in that, comprising:

1) the unified Network Interface Module chip drives interface of definition, unified Network Interface Module property and structure and unified frequency point information structure;

The unified Network Interface Module chip drives interface of described definition is that the chip drives interface definition is one group of driving function corresponding to a series of I2C operations;

The unified Network Interface Module property and structure of described definition be all property definitions of Network Interface Module in a Network Interface Module structure, comprise in this structure: signal load mode type, the I2C address, reservation flag position, and a series of function pointer; Each function pointer all points to a driving function;

The unified frequency point information structure of described definition be with DVB-S, DVB-C, three kinds of dissimilar frequency point information of DVB-T all as the member of a sharing body structure, number distinguish by system banner;

2) Network Interface Module is driven identification, survey different I 2C address answer signal, draw the system banner number of current network interface module;

3) according to step 2) in the system banner that obtains number, Network Interface Module is driven loading, described driving loading procedure comprises: according to the different system identification number, system gives different values for Network Interface Module structure member also will be corresponding one by one with a series of pointers corresponding to the driving function of different I2C operations.

2, by the described digital TV set top box network interface module loading method of claim 1, it is characterized in that described step 2) comprise the steps:

21) find Network Interface Module: by all possible I2C address in will tabulate one by one communicate trial, monitor response, thereby whether the discovery system connects corresponding Network Interface Module;

22) judge the Network Interface Module model; At first, tentatively conclude the model of channel demodulation chip, send the id that the corresponding command reads the channel demodulation chip; Correct as id, can finally confirm the chip model, if read less than corresponding id, promptly confirmation step 21) wrong, need return step 21); Behind the signal of judging the channel demodulation chip, further judge tuning chip, after obtaining tuning chip id, just can judge the model of current network interface module according to the corresponding lists of the model of this two chip block and Network Interface Module and chip model;

23), generate corresponding system banner number according to the model of Network Interface Module and the vendor code and the system profile table of system the inside at that time; Obtain to enter step 3) behind the system banner number.

3, press the loading method of the described digital TV set top box network interface module of claim 1, it is characterized in that, the hardware interface that also comprises unified Network Interface Module and mainboard, this hardware interface adopts the double needle interface of 34 pins, and this interface has comprised Network Interface Module power supply interface, TS stream interface and control and replied interface line.

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