Mobile phone test-resend
Mobile phone testing is a big topic, involving hardware testing, software testing, and structural testing, such as stress resistance, wrestling, fatigue resistance, and low temperature resistance. The structural design is unreasonable, it will cause stress concentration and deformation of the shell. for mobile phone flip and lid failure, there are other serious problems. Hardware testing generally has strict physical and electrical indicators, as well as specialized instruments. The instruments here are not to be said. Generally, if they are professional testers, they will not be unfamiliar with words.
Mobile phone testing generally refers to software testing, which also shows the importance of software on mobile phones. On the one hand, it also shows the difficulty of mobile phone testing. Because he had to perform tests with clear indicators, strict operating procedures, and various instruments. The mobile phone tests described below are generally mobile phone software tests, which will not be repeated in the future.
Before explaining the mobile phone test, I think we should understand what is embedded into the municipal operating system. This is a fashionable term. Although we are already surrounded by products embedded into the municipal operating system, however, it may not be clear what an embedded operating system is, and there are not many lectures in the school class, so many people feel that Yunshan dance covers this.
Simply put, an embedded municipal operating system is an operating system specially developed to complete a specific function. The functions of this operating system are clearly defined. Unlike large operating systems, this system has a wide range and a huge world, and the embedded operating system only provides one or more functions.
Let's talk about the particularity of mobile phones, that is, to limit the response time. That is, the real-time operating system. If a call cannot be answered within 90 seconds, the other party will be suspended. Your operating system has not been reflected yet, so this operating system will undoubtedly fail. This is a requirement for real-time embedded operating systems.
As a tester, you must understand this. Maybe you do not need to care about these aspects for some software developers, because you only need to understand the entry instructions and exit instructions of your modules. But not the tester. Advanced testers should understand the characteristics of the embedded operating system. This system is not like windows, and a graphical interface can be used for input and output, or the command line mode of d OS, you need to write an editor, write an interactive interface, and write an input and output interface. In Windows, you do not need to consider hardware issues by using some APIs and MFC, because the system has been completed, while windows focuses on separation from hardware, it can protect the system from intrusion. Embedded in the city system. These requirements are related to the hardware information. During mobile phone testing, software faults may not be caused by software errors, or because the combination of hardware and software is not considered perfect.
Therefore, while learning about the operating system, we also need to know the performance of other mobile phone hardware, such as CPU, such as memory.
The CPU processing and computing power is measured by MIPS. Of course, the faster the better, but it is also related to the cost. I don't know the CPU of Motorola t39, but because it is a PDA, it is also a handwritten screen, so the menu is particularly slow. Special Instructions need to be made on the storage, because the storage here is very special, unlike the PC, the mobile phone does not have a hard disk!
Generally, the programming languages of the embedded system are C and the most common languages. For example, C ++ uses assembly at the beginning, but the compilation is hard to understand and is not easy to transplant. It is gradually replaced by C. However, even so, when starting a program, it is necessary to start the board, that is, the circuit board still needs to be completed in some assembly languages.
As a program embedded in the municipal system, it is no different from the program running on the PC. The only difference may be that the program runs on the PC, you can see the results-if you use the output statement, here you are looking at the results of the promotion. Unless you add the L Cd hardware, then write the LCD driver, and then write the display program. Write an embedded City Program, and everything should be done by yourself.
If our mobile phone does not think that the power is cut off, or the power is consumed to a certain extent, it will be used all the time. Therefore, the mobile phone program is always running, that is to say, there is always a loop. This should be a good material for understanding embedded city programs-embedded programs are an infinite loop program. Unless you turn off the power supply and power supply factors, there is also a test point here: hardware interruption is the highest level, and it will terminate your program, even if your current program level is very high, such as the call, if there is no power, everything will o ver.
The mobile phone program is an infinite loop program. When will it jump out of this infinite loop? If you are not happy about the shutdown, remove the battery because it may enter an endless loop and the shutdown key becomes invalid, so you have to remove the battery.
Here, I would like to elaborate on storage, because many mobile phone problems are related to storage, and many problems are related to storage. Computer storage is the key, while mobile phones are the key because computers have hard disks for storage, and all the mobile phones are in the memory.
There are several types of memory: Ram random memory, Rom random read-only memory, and some flash memory, as well as electronic programmable storage and non-Easy loss storage. One by one. Ram random memory, including SRAM (static RAM) DRAM (Dynamic RAM ),
SRAM, as long as the power is on, it will be saved. We call and some of the last dialing numbers are temporarily in the SRAM and will not immediately write the call records. It is written only when it is shut down normally. If it is battery, it will not be written into the phone call record. If there is a call that has been made but not recorded in the call record, this memory may be related to errors in your software or hardware. DRAM is rarely used on mobile phones because it takes a short time to retain data. In terms of price, SRAM is very expensive, while DRAM is very cheap.
There are also several types of Rom. The prom programmable ROM and EPROM can erase the programmable Rom. The difference between the two is that the prom is one-time, that is, after the software is filled in, it will be finished. This is an early product and cannot be used now, e-prom is a general-purpose memory, which is inconsistent with mobile software products and generally uses less Rom.
Other Flash files. This is the most memory used by mobile phones recently. This storage combines the strengths of ROM and Ram, but not Ram or ROM. A large number of NVRAM non-Easy memory is used by mobile phones. Similar to the SRAM property, the eeprom electronics can erase programmable memory. Future generations of flash memory and Rom. The mobile phone software is generally placed in the EEPROM, And the EPROM is erased by ultraviolet light, while the EEPROM is wiped out through electronics, of course, the price is also very high, and the write time is very long, the write is very slow, therefore, the phone number mentioned above is generally put in S Ram first, instead of writing the eeprom immediately, because there is a very important job to do at that time-call. If the phone number is written, A long wait is unbearable for users. NVRAM is a very special memory. It is similar to SRAM, but the price is much higher. Because some data is really important, it must be kept after power failure, so it can only be stored here, generally, data related to personal information is stored here, for example, data related to the S im card. The capacity is only several hundred bytes.
Flash memory is the first choice for all mobile phones. It combines all the advantages of the above, does not lose data (NVRAM) fast reading, and electronics can erase programmable (EEPROM), so a large number of mobile phones are now used.
Having said so many memories, it may be a bit confusing. Where are so many memories used? in mobile phone development, all kinds of memory have been used. As for now, the storage used by various mobile phones is different. This is related to the cost. The price of various types of storage is different. Based on the optimal cost-effective combination, it is determined by the designers. Some of them are optional and some are necessary, it is determined by the mobile phone solution. We understand that it is only a variety of storage performance and features, and we can determine the cause of the error during testing.
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White box testing of mobile protocol Station Software
The mobile phone software test list is based on the test content, including the above MMI and the bottom protocol. The flexibility of MMI is different from the personalization of various manufacturers and the users of mobile phones. The focus of MMI varies based on basic calls, short messages, and data functions. Therefore, the focus of testing is different. The test methods are different. But the protocol is different, and the protocol is unified. Although you can implement different methods, the functions must be the same. Different from MMI, although both chat, some use short messages.
Chat, some use push chat, and the protocol software has a compliance specification-the protocol specification specified by ETSI, unified command specification and unified standard. Messages (term, not in software programming, or communication term) are fixed. For protocol testing, there are many tools and companies for software testing because there are standards to be followed and specifications to be available. Automated testing should be automated. Otherwise, the testing capability should be based on people, no one can guarantee its absolute reliability, and there is no such large manpower to perform the test carefully.
Generally, white box testing is strict and labor-intensive. Therefore, automated testing tools are often used. This reduces manpower and test time. Which of the following tools is better? It involves different needs and costs. If you want to buy a product, you will be given a demo version and a one-month evaluation period. This evaluation version will familiarize you with the advantages and disadvantages of the product and your operations. Test Tools generally have secondary development functions, that is, you can write scripts on your own and make some changes to different software platforms. In this way, you can write test case test columns as needed. Of course, even if you use automated testing, You still have no idea, and you should take a closer look at the code. Analyze the process, understand its meaning, a very small problem, the error protection is not well done, generally this problem is the most, the error protection mechanism is not well done, will cause such a serious problem of crash. This is a white box test for protocol code. If you are testing the purchased protocols, there are usually instruments to simulate a network base station for testing. However, such an instrument is very expensive and testers should be familiar with the ETSI protocol. I did not directly participate in white-box tests for protocols, but I used practise to test the coverage rate of the tested software. I was surprised that the general hitting (Tracking) this also reduces the program efficiency, and I want to test the program efficiency and other projects to consider the CPU, and the program's work must be closely related to the CPU, now, when the CPU runs the program, it also requires hitting. Are the tested indexes and actual inconsistencies not reaching the real level? This product (Buffalo) said that it generally does not take up CPU time. After I think about it for a long time, I want to consult, telling them that this is their patent and there is no such thing to tell. Because this test tool is for the platform, if your platform does not support it, you cannot use it. There are also integrated testing and so on, which are described in detail in the introduction of the software. If you want to test the protocol in white, you must be familiar with the relevant Protocols. Otherwise, you must be familiar with the development language.
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1. Classification of the computer industry
In the past, we divided computers into large-scale computers, minicomputers, and micro-Computers Based on the computer architecture, computing speed, structure scale, and application fields. In this way, we organized the division of disciplines and industries, this classification has lasted about 40 years. With the rapid development of computer technology in the past 10 years, the actual situation has undergone fundamental changes, for example, the personal computer (PC) defined by the end of 1970s, such
Today, it has occupied 90% of the global computer industry, and its processing speed exceeds the definition of large and medium-sized computing machines. With the extensive penetration of computer technology and products into other industries, the application-centric classification method has become more practical, that is to say, computer embedded applications and non-embedded applications are divided into embedded computers and general computers. The general computer has a standard form of computer. By assembling different application software, the general computer is similar in appearance and applied in all aspects of society. Its typical product is PC; embedded Computers are hidden in various devices, products, and systems in the form of embedded systems.
2 Embedded Systems)
The embedded system is defined: A dedicated computer system centered on applications, based on computer technology, where software and hardware can be tailored to the functional, reliability, cost, volume, and power consumption requirements of the application system. The number of applications of Embedded Computers far exceeds that of various general-purpose computers. external devices of a general-purpose computer include 5-10 embedded microprocessors, the keyboard, mouse, soft drive, hard drive, display card, display device, modem, Nic, sound card, printer, scanner, digital camera, USB hub, etc. are all controlled by embedded processors. It is an application field of Embedded Computer in manufacturing industry, process control, communication, instruments, instruments, automobiles, ships, aviation, aerospace, military equipment, and consumer products.
