Traditional text storage
Clay plate/bell tripod/oracle bone/papyrus/parchment and other text storage
Traditional archaeologists and historians believe that cuneiform originated from the peculiar hunting and fishing lifestyle of Mesopotamia. This is a common view, and it is widely held in western encyclopedias. The earliest forms of cuneiform writing, mostly images, appeared around 3400 BC. By 500 BC, the script had become the medium of commercial communication in most parts of Western Asia. Cuneiform was in use until about the first year of the Christian Era, as Latin is today.
With writing came the ability to record past data. However, it is all stored by hand.
These histories are not repeated here
Paper making and movable type printing
Paper making and brushing are among the four great Inventions of China.
In 105 AD (Western Han Dynasty), CAI Lun improved the papermaking technique, which was followed by the improvement process. The Tang Dynasty made bamboo paper, which marked a major breakthrough in papermaking technology. Then came a series of improvements in the West.
Mud movable type was invented by Bi Sheng in 1041-1048 AD (Northern Song Dynasty). It marked the birth of movable type printing. This was followed by a long period of improvement, and after 400 years in Europe,
Between 1440 and 1445, The German Johannes Gutenberg’s lead type, letterpress printing — Victor Hugo called printing the greatest invention in the world.
In the early Middle Ages, books were a symbol of wealth. If anyone has a library. That was very rich, for in those days books were painstakingly copied by hand. Monks and scribes were often employed to do this work, at considerable expense, of course. The advent of the printing press changed all that and accelerated the spread of knowledge and culture during the Renaissance.
Punched tape paper storage
The earliest storage medium – punched paper cards
This is one of the earliest data storage media, invented in 1725 by Basile Bouchon to preserve patterns on printed cloth. But its first real patent, filed by IBM’s founder, Professor Herman Hollerith, on Sept. 23, 1884, took almost 100 years, until the mid-1970s.
In 1888, he invented the automatic tabulating machine, the first data processing machine to use punch cards. Tabulating machines (punch-card data processing techniques) were used with great success for the 1890 and subsequent U.S. census.
IBM’s forerunner, the CRT-Computing-Tabulating-Recording Company, was set up in 1911 to make gauges, timekeeping equipment and Tabulating machines.
In 1923, CTR invented the first electric puncher, which was much faster and more accurate than the manual puncher. In the late 1920s, IBM invented an 80-column punch card that was the “high-density storage device” of the time. The “IBM Punch card” became the industry standard.
Tom Watson Sr., who ran the company from 1914 to 1956, was an ambitious leader who changed the name of the company to International Business Machines in 1924, which became known around the world.
In software, IBM has also made remarkable contributions. It developed the FORTRAN, COBOL and SQL programming languages and invented relational databases and speech recognition software.
IBM dominated computing from the 1960s to the early 1980s, but its success led to antitrust investigations. Outside interference and blind expansion brought IBM to the brink of collapse in the early 1990s, but it remains a giant today.
The picture above is a typical example of a perforated paper card – made in 1972 and capable of punching 90 rows of holes. Obviously, you can see how little data can be stored on this card, and how few people actually use it to store data. It is generally used to save the Settings of different computers.
Storage principle of punch card
Empty space is 1 and empty space is zero. Testing for holes can be done with electro-optical or mechanical contacts.
The input is drilling, with an awl, with a punch machine can be, I use an awl to change the tape, used in the control of the wire cutting machine.
In the early punched card/tape, there was a set of spring-fixed probes inside the reader. First, all the probes were pulled up, the tape moved, and then the probe was released and dropped. If there was no hole in the tape, the probe would be blocked and the corresponding circuit would be disconnected. Otherwise the probe can fall through the hole, circuit path. Each probe corresponds to a potentiometer, with a path of 1 and a break of 0. After reading, all probes are pulled up, the tape moves forward, then the probes are released, and the cycle begins.
Capacity larger than punched card – punched paper tape
Alexander Bain (inventor of the fax machine and telex machine) first used perforated tape in 1846. Each line on the tape represents a character, and the capacity of perforated tape is obviously much larger than that of punched cards.
Storage development from recorder
Acoustic vibrator
In 1857, French inventor Scott (Scott) invented the sound wave galvanometer, and obtained a patent on March 25, 1857. Scott’s sonic vibrograph was the first primitive tape recorder, the progenitor of the phonograph. It transcribes sound to a visual medium, but cannot be played back after recording. At first, the pinger recorder transferred a recording onto a glass plate. A later version used a piece of paper placed on a drum or roller. Another version pulls a line representing sound waves onto a roll of paper. The acoustic recorder was invented while studying acoustics in the laboratory. It was used to determine the frequency of a tone and to study sound and language. It was not until the invention of the phonograph that it was generally understood that the waveform recorded by the phonograph was a sound record that required only a playback device to reproduce the sound.
The phonograph
November 21, 1877, American inventor Thomas Edison announced the invention of the world’s first phonograph – a can convert sound waves into metal needle vibration, and then recorded the waveform on a cylindrical wax tube tin foil. When the needle follows the burned track again, it can reproduce the sound left behind. Since then, recording technology has enabled mankind to obtain the means of recording, storing and replaying sound information.
In 1878 Edison founded the phonograph company to produce a commercial tin foil drum. It was the world’s first sound carrier and the first commercial phonograph.
Flat phonograph
In 1887, Emil Berliner, a German in the United States, obtained a patent for the phonograph, which successfully developed the disc record (also known as the butterfly record) and the plane phonograph.
In 1891, Belina successfully developed a record made of shellac as raw material and invented the method of making records.
The working principle of
The sound vibration property of the first recorded on the record, is on record to draw some winding trough (where the “winding” he recorded the sound source attribute), we are in the play, the needle into the slot, when the disc rotation, vibration trough and will force the needle on the record, so there was sound.
Reduction is the key equipment of sound pickup, it has a needle, a slide on the microgroove orbit relative (pick-up itself only axial movement, the record on the turntable and Angle of rotation speed), will track vibration produced by uneven pit is converted into electrical signals, then through a series of demodulation, amplification and finally sperker, drive the horn sound signal.
Magnetic recorder
In 1898, Danish scientist V.Poulsen invented magnetic tape recorder (wire tape recorder) using the principle of remanence magnetism. That is, iron can be magnetized and demagnetized, but after demagnetization, there will still be a very small magnetic residual, which is called remanence. The greater the initial magnetic force applied, the stronger the remanence; The smaller the initial magnetic force applied, the weaker the remanence. Then change the change of sound wave into the change of electric current, and then change the change of electric current into the change of magnetism through electromagnet, apply this magnetic force on the iron wire, and then leave the residual magnetism. In this way, the change in sound becomes the change in remanence, and recording can be done. At that time, there was no breakthrough in the research of the device to turn sound waves into electric current. With the development of telephone research, this problem was solved and immediately used in Poulsen’s recording device.
Personally, this may be the ancestor of the hard disk
Tape recorder
1928 Fritz Pfleumer company invented the recording medium tape.
In 1935, The German company General Electric made a tape recorder,
Recorded telephones and tapes were first shown at the 1935 Radio exhibition in Berlin. From then on magnetic tape came into our sight as the latest “sound storage” medium.
Japanese scientists in 1938 discovered the alternating current magnetic recording principle
Principle of Tape Recording
A magnetic tape recording head is actually a hoof electromagnet with the poles close together, leaving only a slit in the middle. The whole head is enclosed in a metal case. The tape base is coated with a layer of magnetic powder, which is actually a lot of ferromagnetic particles. The tape is close to the recording head through, the audio current makes the recording head gap magnetic field strength, direction constantly changing, magnetic powder on the tape is magnetized into a magnetic pole direction and magnetic strength of different “small magnet”, sound signal is recorded on the tape. The structure of the playback head is similar to the recording head. As the tape passes in front of the slot in the playback head, the magnetic field generated by the “little magnets” on the tape passes through the coil in the playback head. Because the polarity and magnetic strength of the “small magnet” varies, the magnetic flux it produces in the coil is also constantly changing, so the coil induces an electric current, which can be amplified to produce sound in the speaker. An ordinary recorder often uses a single head for recording and playback.
Electronic applications — counter tubes
In 1946 RCA started work on the counter tube, which was used in the early huge tube computers. A tube was 10 inches (25 cm) long and could hold 4,096 bits of data. Unfortunately, it was extremely expensive, so it was a flash in the pan on the market and soon disappeared.
That same year, the ENIAC computer was born in 1946. The computer uses a vacuum tube system. ENIAC computers are huge. It occupies almost 170 square meters in a building at the University of Pennsylvania. The ENIAC was unlike any computer ever made. Its number-crunching was lightning fast, at least compared with older computers.
Counter principle, can see “counter, what is the operation of the counter?”
Large tape recording – disk tape
Magnetic tape was first used for data storage in 1951. The tape equipment is called UNISERVO and is the main input/output device for the UNIVAC I computer. UNISERVO’s effective transmission efficiency is about 7,200 characters per second. The tape mechanism is metal and is 1,200 feet (365 meters) long, making it very heavy.
Because a single reel of magnetic tape could replace 10,000 punched paper cards, it became an instant success, becoming the most popular computer storage device until the 1980s. Back in the late ’80s, everyone would get together and watch old movies, and look at this giant disk going around, and this is a reel tape.
The most treasured memory – cassette tape
The cassette tape is probably one of the most cherished memories of the 1980s. It is obviously a type of magnetic tape, but it is so popular that it needs special mention. It was invented by Philips in 1963, but didn’t catch on until the 1970s.
It was a very popular way to store data for personal computers in the late 1970s and 1980s, such as the ZX Spectrum,Commodore 64, and Amstrad CPC.
The typical data rate for a typical cartridge is 2kb/s, and each side can store approximately 660KB of data for about 90 minutes.
A single DVD9 disc can hold 4,500 of these old tapes, and it would take 281 days to read them out. So tapes were gradually phased out.
But now SONY’s latest tape has an incredible 18.5 gigabytes of storage per square inch, five times the previous record set by IBM in 2010. It is 74 times larger than the capacity of the tape used for archiving storage. With that kind of storage density, a single small tape can hold 185 terabytes of data. But it is impossible to turn the market around.
At present, large museums keep data, or the first to promote tape. The cost is cheap. But the point is read full. But for archival backup. It’s not a problem.
Researchers at The Japanese company Fujifilm and in Zurich, Switzerland, have developed a new type of ultra-dense tape called the Linear tape File system. The box is 10cm long, 10cm wide and 2cm high and can store 35TB of data.
The storage technology is likely to be used first for the Square Kilometer Array, the world’s largest radio telescope array. The array will be built in the southern hemisphere and will consist of thousands of antennas. The Square Kilometre array will be operational in 2024, generating an estimated 1PB(100GB) of compressed data per day. According to the Information Storage Industry Association, at least 120,000 hard drives a year are needed to have a storage capacity of three terabytes and a 10-year lifespan.
According to a 2010 study by The Clipper Group, a technology consulting firm in Leye, N.H., data centers using hard drives consume 200 times as much power as tape libraries of The same size.
Super long storage device – magnetic drum
A drum is 12 inches long and can make 12,500 revolutions a minute. It is used as main memory in IBM 650 series computers and can hold 10,000 characters (less than 10K) each.
Hard disk storage
Now the main stream of computer data storage, or mechanical hard disk. VeryCD hung for 2-3 years, cost reasons, or cost-effective hard disk.
“Heavy” big breakthrough – the world’s first hard disk machine
On September 13, 1956, IBM released the 305 RAMAC hard drive. The related computer was unremarkable, but revolutionary in storage capacity — it could store “massive amounts” of data, “up to” 4.4 MEgabytes (5 million characters), on 50 24-inch hard disks. By 1961, IBM was producing 1,000 305 computers, which IBM leased for $3,500 a month.
As you can see above, the world’s first hard disk drive weighed more than a ton. Today’s hard disks are as small as 0.85 inches and weigh less than 10 grams.
The operating voltage of the hard disk is +3.0V. Standard power consumption for reading and writing is 0.65W. The overall size is 3.3×32.0×24.0mm3 and the weight is less than 10g. For impact resistance, the hard drive can withstand 1000G of acceleration in 2ms.
Optical disc storage
VCD is said to have been invented by a researcher in Xi ‘an, China, and not patented. But discs, hours out are a must.
The first video CD – LD CD
Compact disc technology was invented in 1958, but it wasn’t until 1972 that the first video compact disc was released, and it went on sale six years later in 1978. Discs at that time were read-only, unable to write, but able to hold VHS-quality video, making them attractive.
Principle of disc
One-time recorded cd-r discs mainly adopts phthalocyanine organic dyes, when this CD in the burn, laser on substrate with organic dyes, burn, burn directly one by one, the “pit”, it has a “hole” and not “pit” state is formed ‘0’ and ‘1’ signal, this one by one, the “pit” can’t reply, This means that when burned to a pit, it will remain permanently as it is, which means that the disc cannot be erased again. This string of zeros and ones forms the binary code that represents a particular piece of data.
In the case of a repeatable erasable CD-RW, it is not an organic dye, but a carbon substance. When the laser burns, instead of burning one pit after another, it changes the polarity of the carbon substance, and by changing the polarity of the carbon substance, it forms a specific code sequence of “0” and “1”. The polarity of the carbon material can be changed repeatedly, which means the disc can be erased repeatedly.
Smaller and larger – compact discs
Our common 5 inch CD, developed from LD CD, but it is smaller, larger capacity. It was jointly released by SONY and Philips in 1979 and launched in 1982. A typical 5-inch DISC can hold 700MB of data.
Using infrared laser – DVD disc
The DVD is a CD that uses a different laser technology. It uses an infrared laser of 780 nanometers (standard CDS use a red laser of 625 to 650 nanometers), which allows the DVD to hold more data in the same area. A dual-layer DVD can hold up to 8.5GB
State-of-the-art storage – Blu-ray DVD, HD-DVD
The two competing disc technologies, Blu-ray and HD-DVD, are getting the most attention. Blue lasers allow storage capacity to grow further, and for now, it looks like Blu-ray DVDS are more popular. But taking a longer view, perhaps a Disc called the “Holographic Versatile Disc” can offer up to 160 times more capacity than a Blu-ray DVD – up to 3.9 terabytes, or 4,600 to 11,900 hours of mPEG4-formatted movies.
Because of people’s life, information is becoming more and more expansive, making information storage especially important. Resulting in the rapid development of data storage. Finally, we compare the current popular DVD storage with the previous storage products, we can intuitively see the development of data storage. Today’s DVDS are the equivalent of 90 million punched cards, 6, 000 floppy disks, and 4, 000 lily tapes.
Floppy disk storage
IBM invented the floppy disk in 1969 as an 8-inch blob that could hold 80K of read-only data. Four years later, in 1973, a smaller, 256K floppy disk was introduced: it could be read and written repeatedly. The trend began with smaller and smaller disk diameters and larger and larger disks. By the late 1990s, we could find 3.5-inch floppy disks with 250MB capacity.
The mid-1970s to the early 2000s were the most dominant storage devices.
The recording format of floppy disk data
When storing data on a floppy disk, you need to divide the floppy disk into several small areas according to a certain format. The disk is divided into concentric circles, called tracks, each of which is divided into sectors, each of which can hold a certain amount of data. Sectors must be numbered for easy access to files. This number is called the floppy disk address. The floppy disk address consists of the track number, side (head) number, and sector number.
(1) Surface (head) no. 0 faces head no. 00 and 1 faces head No. 01.
(2) Track number. Starting from the outermost 00 tracks of the floppy disk and arranged from the outside to the inside, the 3.5 inch high-density floppy disk has a total of 80 tracks.
(3) Sector number. The serial number of each sector is the sector number, and the number of sectors is the same, although the recording density of the outer track is different from that of the inner track. 3.5-inch high-density floppy disks have 18 sectors per track. Each sector contains 512 bytes. Capacity: 2 x 80 x 18 x 512=1474560 bytes.
(4) cluster. The system groups sectors into clusters. Files are stored in clusters rather than sectors on floppy disks to reduce the amount of FAT. A cluster consisting of 2n(n=0, 1… 6) A cluster consists of sectors. The number of sectors contained in a cluster is related to disk capacity and FAT table format. For disks less than 2M, a cluster has only one sector. Each file occupies at least one cluster.
Figure 6-3 shows the floppy disk sector format. Each track is composed of three parts: the front area, the segment area and the back area. Each sector has an ID field, a data field and two gaps. The track number, head number, and sector number of the floppy disk are recorded in the ID field.
The formatting of a floppy disk
Floppy disk formatting is the division of record areas on the floppy disk; Write all kinds of mark information and address information; Determine how data is recorded on disk; The process of determining the number of tracks per disk, the number of sectors per disk, and the number of bytes for gaps, synchronization fields, and identifiers is called physical formatting of a floppy disk. At the same time, formatting also establishes the disk’s system format on the floppy disk, called system formatting. The floppy disk has to be formatted before data can be stored on it.
A reformatted floppy disk with all data on it erased.
Flash memory, semiconductor memory
Solid state drives
Solid State Drive (Solid State Disk or Solid State Drive, referred to as SSD), commonly known as solid-state Disk, solid-state Disk is made of solid-state electronic memory chip array, because the Solid capacitor is called Solid in Taiwan English. SSDS consist of a control unit and a storage unit (FLASH chip and DRAM chip). Solid state disks (SSDS) are the same as common hard disks in terms of interface specifications, definition, functions, and usage methods, and in terms of product appearance and size. It is widely used in military, vehicle, industrial control, video monitoring, network monitoring, network terminal, electric power, medical, aviation, navigation equipment and many other fields.
Two to three times faster than a mechanical hard disk.
Reference article:
The memory principle and history blog.csdn.net/yang8899998…
In one hundred IBM 24 moment: from tabulator to supercomputers news.mydrivers.com/1/196/196557.htm
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