What is a flash drive and what is a flash drive used for
52 2021-07-28 00:45
The usb drive is a common and frequently used storage media in our life, most people use it to store things to use, before understanding this knowledge, I and everyone else. With the following knowledge, we will now have a deep understanding of the usb drive, a small thing that allows us to use it as we wish. Now the hottest thing with usb drive is to make usb drive boot disk, we can pay more attention to it.
Chapter 1: Overview of usb drive
A. What is usb drive
usb drive is the abbreviation of USB drive, and usb drive is just the harmonic name of usb drive.
usb drive is a kind of flash memory, so it is also called flash drive. The biggest feature is: small and easy to carry, large storage capacity, cheap. It is one of the mobile storage devices.
Second, common usb drive brands
Kingston, Lanco, Taipower, Patriot, Apacer, Lenovo, USB drive, Newman, Tsinghua Ziguang, Yijie, Biao Wang, Aomega, Hyundai, Founder, BenQ
Three, usb drive storage principle
The computer converts the binary digital signal into a composite binary digital signal (adding instructions for allocation, verification, stacking, etc.) to read and write to the usb drive chip adapter interface, which is assigned to the corresponding address of the EPROM2 memory chip through the chip processing signal to store binary data and realize the data storage. EPROM2 data memory, its control principle is voltage control gate transistor voltage high and low value (high and low potential), gate transistor junction capacitance can save voltage value for a long time, that is why usb drive can save data after power failure.
Fourth, the structure of the composition
From the composition of the structure of the USB drive there are three parts: the main control, Flash memory chip, crystal (clock circuit), USB interface.
The main control is the bridge to communicate with the flash memory chip chip, and they all need crystal oscillator to work.
The main control to work at a certain frequency, and FLASH communication also need clock signal transmission, so I simply analogy, the main control is like the computer CPU, Flash memory chip is like the storage of computer hard disk, and the computer CPU work needs pulse signal, but also the clock circuit, the principle is the same.
1, common usb drive master control as follows.
Xinchuang 3S(Solid State System)
Wise Wing SMI
Lian Sheng USBest (UT)
Time Minxin MXTronics
Supertech Micro Ameco
I think iCreate
2、Common usb drive flash memory chips
There are three kinds of MLC particles, SLC particles and TLC particles. Their specific meanings and differences are as follows.
SLC = Single-Level Cell, that is, 1bit/cell, fast speed and long life, super expensive (about MLC 3 times more expensive), about 100,000 times erase life.
MLC=Multi-Level Cell, i.e. 2bit/cell, average speed, average life, average price, about 3000--10000 times erase life.
TLC = Triple-Level Cell, that is, 3bit/cell, there are also Flash manufacturers called 8LC, slow life, cheap, about 500 times the erase life, no manufacturer can do 1000 times.
Common brands: Samsung, Toshiba, Sandisk, Hyundai, Magnesium, etc.
(1) USB interface
USB interface has four lines, respectively: 5V power, data transmission line D + and D-, ground.
(2) USB port to transfer data speed
USB transmission rate theoretical values.
USB1.0 Low Speed (Low Speed) transfer rate of 1.5Mbps.
USB1.1 full speed (Full Speed) transfer rate of 12Mbps.
USB2.0 High Speed (High Speed) transfer rate is 480Mbps
The theoretical transfer rate of High Speed is 480Mbps, i.e. 60MBps.
The full speed theoretical transfer rate is 12Mbps, i.e. 1.5MBps.
Note: The above mentioned is Mbps, not MBps.
1Byte bytes = 8bits bits. The usual reference to storage space is byte.
V. Usb drive uses
1、Used as a disk to store files
2, used as a boot disk to start the computer
3, used as a CD drive to install the system
4、Used as HDD to boot and install the system
5、Used as a hard disk to install the system inside
Chapter 2: usb drive use
The basic use of the need to say more, mainly for some special uses and personalization, to do some elaboration
A, usb drive personalization
Now there are many usb drive through the installation or mass production software to personalize usb drive, but I think these take up U space, even if the usb drive space is large, but always feel cumbersome, so the introduction of some small skills of things, of course, not into the eyes of the master, kindergarten, pediatrics and other words or do not say, this common sense left to the useful people.
1, usb drive drive custom icon.
(1) first select an icon you like, the icon extension is: ico.
You can search for software that makes pictures in this format, or a converter to make an ICO file.
(2) Copy this icon file to the usb drive, and create a new text document in the usb drive.
(3) in the text document write the following content:
where xxx is the name of the icon file you want.
(4) rename this text file to autorun.inf
Note: Be sure to change it to .inf, not the original .txt. If the icon of this text file becomes a yellow gear after the change, it means that the change is correct.
Unplug the usb drive and plug it in again, and you will see that the usb drive icon becomes the icon of your choice. This method can also be used in mobile hard drives or CD burning.
2. usb drive background customization.
Open usb drive always white background, very fatigue, then modify the background how?
(1) first select a background image you like, copy it to the usb drive.
(2) Create a new text file and copy the following content into it:
where aaa.jpg is the selected image file, PNG and other formats are also available (with extensions).
(4) Rename the text file to Desktop.ini and finish the modification. Refresh it and you can see it.
The above four files involved can be hidden to avoid accidental deletion. After modifying the icon, you need to re-plug the usb drive once before you can see the effect. Refresh after the background is changed, and you can see it.
3、Mass production change usb drive information
When the usb drive is plugged in the information displayed is what you want, more personalized.
As for the mass production is discussed below.
Second, used as a boot disk to install and maintain the system
1、Computer boot disk
(1) DOS boot disk
The initial DOS boot disk is now rarely used, but there are still available, such as made into a DOS boot disk, put in GHOST tools to restore the ghost system, but also very practical, which is very suitable for small usb drive, such as the usb drive below 32MB. simple practice, there is an option in the usb drive format, is to do If you want to do this, there is an option to do a dos boot disk, and the format will be written automatically. You can also use tools and software, such as USboot, in addition to the DOS home to provide a key to ghost the usb drive version is modified USBOOT, installed after the ghost file, partitioning tools, antivirus tools, etc. have been done into the boot disk, it is very convenient.
(2) PE boot disk
In fact, PE boot disk can be mass-produced to do the boot disk, but also in the form of HDD to do the boot disk, the general PE ISO disk has been integrated with this tool, the U formatted into the HDD boot form, PE can be installed to maintain the computer system. Now a lot of PE installation to usb drive or removable hard disk as a mobile system, in fact, very good and convenient, only speed limitations.
(3) Windows XP Embedded\LINUX and other usb drive system
Many people do XP etc. into the usb drive as a mobile system, in the linux community there is also the linux system into the usb drive or mobile hard disk, such as prayaya livesystem, is a mobile linux system.
What is a flash drive and what is a flash drive used for