Although the USB flash drive is small, it can be a big task.

It's not difficult to use a tiny USB flash drive to start a computer. However, it is not easy for you to describe this matter, especially when facing a group of children (note: this is not about everyone, but now I want to write a USB flash drive user manual for these children.) Yesterday morning, I spoke to four students of Fudan University about the usage of this small item in the classroom 107 of the first teaching building of Peking University.

Two days ago, how long is the life of a USB flash drive? And how to estimate the natural age of a USB flash drive. I have explained some basic information about the USB flash drive, the U disk manufacturing industry has become a very mature industry, and many big-name companies are involved. The reliability, quality, quality, price, and quantity of USB flash drives have made significant progress over the past one or two years. Now, we can say fairly that the availability of USB flash drives is beyond doubt.

Looking back at the history of PC computer development, we can see that before the PC Computer leaves the factory, it is pre-installed with a set of operating systems to solve all the installation complexity before leaving the factory, only one easy-to-use PC computer is finally handed over to the user. Undoubtedly, this is Microsoft's achievements. (Self-starting) USB flash drives. Don't look at this inconspicuous little thing. The current situation is the same.

Experiments show that if the computer does not have a hard disk or optical drive, it is easy for people to: before each computer is started, the computer can be started normally by inserting a self-starting USB flash drive from the USB port, directly go to the so-called "User desktop ". As for what is displayed on the user's desktop, how is the panel, tool bar, And button displayed, how can these things be clearly explained to the user (imagine being a "small user", that is, the children, it is not purely a technical issue, but something that the Chinese teacher in the middle school is good. The problem here is that the introduction of related concepts and terms must be gradual and easy to understand, understand, and be interested in. To do this, I had to be overwhelmed. I had never taught in colleges and universities for the rest of my life, but never taught the children. In short, we can imagine a computer classroom without a hard disk. Every child comes to class with his own USB flash drive. In class, ask them to "plug in the disk first and then Boot"; every time the children have enough time, before the class, teach them to "Shut down first, pull the disk later ". On weekdays, the school will teach students to "take a USB flash drive with you, do not lose it at will, and pay compensation if you lose it ". I think it depends on what we put in the USB flash drive if you don't like it.

The children will definitely influence their parents. Parents must learn to configure the BIOS of the home computer according to the U disk user manual, so that the children can smoothly start the computer from the USN port at home. As a result, the parents will inevitably notice the existence of this "Little Thing" (that is, self-starting USB flash drives. If a self-boot USB flash drive is successfully tested in primary and secondary schools, similar experiments can be conducted in any areas where crowds flow and accumulate, such as public areas. Self-starting USB flash drives need to be customized for specific groups and provided to potential users for voluntary selection. Users do not have to worry about the operating system they use. They should be concerned about the specific usage of various self-starting USB flash disks. Self-boot USB flash drive, manufacturers can make sturdy and durable, inexpensive, people love. In the near future, once a self-starting USB flash drive becomes popular, a website dedicated to providing technical support for self-starting USB flash drives will be indispensable.

In our opinion, this is a market that does not include "Autonomous Technology". Anyone can come in and play with it. However, it depends on how you play it. How long is the life of a USB flash drive? How to estimate the natural age of a USB flash drive is attached below this article for your reference.

How long does a USB flash drive last?

Since the launch of a 16 mb u disk in March this year, people have paid more attention to it. In October June this year, the 8 GB self-starting USB flash drive launched by the French company mandriva became more eye-catching. There are also actions in China. At this point, it seems that the prospect of a USB flash disk is bright. However, we have to ask: Can a USB flash drive take on such a huge role if its service life is short? This question must be answered and understood. Relatively speaking,

The history of the USB flash disk is not very short. During his work in toshba, Japan in 1984, Fuji Masuoka found the so-called "Flash Memory", which was announced at the IEEE Conference in the same year. Intel was very keen to launch commercial FLASH products in 1988. In 1989, toshba launched the so-called "NAND" flash memory product with a faster write speed and higher storage density, laying the foundation for the modern U disk family. The structure of the USB flash disk is not complex. The memory of a USB flash disk is composed of several "blocks" in sequence. Each "Block" consists of several "pages" in sequence, it looks like a bookshelf, where many books (I .e. those "blocks") are placed in sequence "). The number of pages in each block depends on the block size. For example, a 128 kb block contains 4,096 pages. At this time, the size of each page is 4 kb (actually bytes, 12 ~ A 16-bit verification code ). Data is stored in some blocks. During information processing, the basic unit of operation is block. For block operations, erase and re-write are two basic actions. It takes a certain amount of time to complete an erasure and rewriting operation. Therefore, flash storage products are classified as "fast and slow. The number of erasure and rewriting times of a block is limited (this is a limitation of Physical and Chemical Properties), and it is called the block life cycle (lifetime ). In general, in terms of business, to ensure that 0th blocks can withstand more than 0.1 million write/Erase times, and other blocks cannot (and do not have to) ensure the long life of the blocks (note: there are some practical technologies to deal with those bad blocks ). At the same time, some practical technologies can greatly extend the write/erase life of blocks.

As we all know, it's just reading information from a USB flash drive. It's not about the length of service life. For example, if you connect a self-starting USB flash drive to a PC computer with larger memory (relatively speaking, it will not damage the USB flash drive if you play for a long time. When using Firefox 3.0 web browser to surf the Internet, it sometimes needs to remember the access history of your web page and must perform some write operations. In this way, the service life of the USB flash drive should be at least 10 years. In fact, the problem is not that simple. Yesterday, I went to Beijing Zhongguancun dinghao electronics city to visit the Patriot U disk repair center and learned that the damage to 90% of the U disk is not due to the long life of the U disk memory, but the "control crystal oscillator" component was burned out. The operating voltage of the USB flash drive is 2.7 ~ Between V and V, it is very easy to cause voltage fluctuations during plugging, leading to faults. U disk maintenance principle is that if a batch of U disk products are found to have a damage rate greater than 1%, they will be immediately requested to stop production. From this point of view, the use of brand-name U disk products on the market still has a certain degree of quality assurance, but the use of the method (after use training), can not be taken for granted.

Note 1: This article has referred to and cited many authoritative works on flash memory at home and abroad, which has some reference value;

Note 2. You must be clear about the bulk purchase of USB flash drives. General U disk sales staff, confused mind, their marketing words cannot believe.

How to estimate the natural age of a USB flash drive

Today, people are familiar with USB flash drives. However, there is still a lack of necessary understanding and correct concepts about its lifecycle. For example, how can we determine the age of a USB flash drive? Note: the so-called U disk is not the actual use time of the U disk, but the natural age of the U disk. What is the natural age of a USB flash drive?

In normal use, the memory in the U disk (that is, the flash chip) will gradually become aging, showing a typical descent curve (the right half of the Life Cycle curve ). The USB flash disk saves some important data. If you leave it in a proper environment and do not use it, the data will be readable after about ten years. However, if you use it frequently, and some of the memory blocks are constantly erased, the so-called "Bad Block" phenomenon will occur. At this time, the storage logic of the USB flash disk (distinguishing logical blocks from physical blocks) will automatically avoid these "Bad blocks" for storage operations (allocated to other physical blocks), just like the processing mechanism of a general hard disk. However, the overall performance of the USB flash disk memory is still decreasing, as the speed of reading data from the USB flash disk is slowing down. This reading speed slows down, and users of the USB flash drive will find it as long as they pay attention to it. At this time, U disk users should pay attention to timely backup of important data on the U disk to avoid unnecessary losses.

Generally, the read speed of the newly purchased USB flash drive is faster, for example, 5 Mb/s. However, after a period of time, the read speed is reduced to half of the original speed, for example, 2.5 Mb/s, at this time, the natural age of the U disk is about to enter "old ". If the natural "Death" of a USB flash drive is ten years old, the old USB flash drive may be seven to ten years old ~ 8 years old. However, the actual usage time of the USB flash drive may be less than 3 ~ 4 years. The main point of this article is to show U disk users that the normal death of the u disk is a gradual process, not all sudden death. Sudden failure of a USB flash drive means that data cannot be read or written normally. How to avoid sudden death of a USB flash disk, the most important thing is to pay attention to the correct use of the USB flash disk on weekdays, especially when accessing or pulling out the USB port, do not make the brute force, resulting in voltage fluctuations, damage the "crystal oscillator" ("crystaloscillator") of the USB flash drive. To get rid of the fear of a USB flash drive, you always worry about the sudden death of your flash drive. On the eve of a USB flash drive's major failure, there must be a precursor. For example, the reading speed suddenly drops. In the near future, USB flash drives will be the companion of every one of us. We cannot understand their "preferences.

(Note: I learned about the natural age of a USB flash disk based on the Wiki definition of USB flash memory (official explanation, the speed of reading a USB flash drive is one of the elements worth your attention. A USB flash drive is life-threatening, and a USB flash drive is a friend of ours .)