By Pragyansharma Polavarapu
(1)
Decades back I often felt perplexed to understand how the simple commands typed on the key board of a computer , a silent machine here on earth , can initiate truly big actions in faraway orbiting satellites.
The computer is not a big roaring machine like a tractor or bulldozer but can in fraction of a second make faraway giant machines , through a coded wireless signal, to start some big actions . The little computer on the table in front of the engineer has connection to the computerized sensors of the faraway giant machines. It is perhaps a yes/no type technical session that goes on between them checking many aspects of the faraway machine.
The silent computer here before the engineer can give commands for launching rockets , for building a sky scrapper, for guiding an airplane in the sky, for helping detect radiations from an atomic reactor , for accurately guiding the blasting of rocks while building dams and underwater power stations etc. There are computerized sensors on the distant machines . Both are interlinked through Client- Server type computer connections or through LAN type networks.
There is also a networking joke . The connection from X’s phone to the phone of a neighbor Y in the same lane is suddenly broken. Then in an instant a new connection is established by TCP/IP through Japan-China-Singapore –Kolkata digital network or even through Antarctica .
On to the screen of our innocent looking desktop/laptop come old Hindi and other classic cinemas, videos of old tennis and cricket classic matches via the Internet . Soon the room becomes full of music and human voices when a video starts playing. We see a thrilling live session of a cricket match now being played . There are loud sounds and cheers. All this magic is done by the algebra like group of software instructions guiding the CPU of the computer. The rules for writing perfect software programs can be created by senior engineers and university professors.
(2)
The computer seems like a magician’s tool. Just as ,when a magician writes some words on a piece of paper and utters a “manthra”, a magic action starts--- a mountain moves a few meters or day changes into night or vivce versa. The computer’s ways are similar to the ways of the magician .But the computers are scientific things breathing mathematics (like humans breathing oxygen ). They process billions of 0s and 1s --- unending streams of digital strings like 0101010101 .
Every modern computer ---be it a desktop, laptop, tablet ,i-Pad or a cell phone,digital camera or a computer chip based modern machine like mixie/ washing machine /air-conditioner/ car /motorbike ---all these have a intelligent micro-processor chip inside. The silicon chips have come to very wide use in such modern machines .We are quite in the computer age .
The real thing is the “software”—a magic formula which makes computers thinking in digital way imitating human logic and self-driving automatically .Hundreds or thousands of standardized “Logic circuits” devised by great electronic engineers and scientists decades ago exist in a computer’s electronic digital brain.
The “electronic logic circuits” are so fast and powerful that they can solve a million mathematical problems like ( 3x2),(3+2),(3-2),(3/2) etc in millionth of a second! The transistor triodes create millions of electrical oscillationsin a second. Such oscillations divide a second into “millionth of second” units of time. The computer’s CPU can create hundreds of “time slices” . In each such “time slice” a separate computer programme( like song, photo , English novel)can be processed . This giant capacity of modern computer is called “time sharing”. There are many such programming techniques.
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In old technology of transmitting photo and sound signals by radio waves--- ( that created commercial radio/commercial television/telephone networking)-- analogue signals were used . The corresponding electrical wave for sound/picture signals was like an endless zig-zag line like the long outline of an endless mountain range with highs and lows.
But in modern computer technology , the analog data signals (whether of printed text/picture/sound and audio/video files) are converted into countless digital strings like 01010101 strings—with countless billions of 0s and 1s. Such data strings look like a train of billions of wagons of rectangular shape and same height. Only such digitalized waves of text/picture/sound can be processed by computer networking technologies like TCP/IP . The great wonder is that all are combined into a single digital stream . The speed of digital wave is 300,000 kilometers persecond. The triode creates millions of oscillations per second. And a second’s time is cut into a million pieces to create several perfect “time slices”. All so wonderful like a magician’s work.
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The computer’s logic circuits are low voltage electric(electronic) circuits. They use the speed of flow of electrons( the speed of flow of electric impulse) to solve mathematics-based computer logic in millionth of second.
We may note that computer treats all actions as so much mathematics processed in 01010101 language . Computer divides a file (say an English essay) into standard sized DATA PACKETS with a destination address code—just like a sealed railway parcel with destination address. TCP/IP does not care about meaning and content and treats every file transmitted on digital network as a set of sealed DATA PACKETS with destination address labels.
Roughly speaking, a data packets in TCP/IP contains digital data equal to a page of 500 to 1500 “computer words” called “bytes”. Each byte has eight or ten binary digits (0s and 1s)
Even the music/ moving picture (audio/video signals ) are converted into digital data packets. All these data packets with destination address codes created in millionth of a second are pushed into the computer highways of internet .
(3)
Simple people not familiar with the inner working of the computer machine feel awed and confused . They do not know how computer gets such power with simple typing of a “software program” --(a set of coded working steps just as in an algebra problem )-- on the key board of computer or by clicking the icon in the active window with mouse button .
In one word we can say the power comes to computer when we give commands to its digital brain through “SOFTWARE INSTRUCTIONS “ in a “SOFTWARE PROGRAM”.
What really is a SOFTWARE PROGRAM? The way of thinking in computer’s brain closely resembles human thinking. This is not surprising because it is only human engineers who created rules for computer’s thinking processes.
(a) In the beginning computer was developed purely as a mathematical calculating machine. . The first electronic calculators like ENIAC and EDVAC --(which even 70-80 years ago could do tough mathematical calculations in millionth of second )---were giant size machines requiring a big air conditioned hall . The currents used were however only of low voltages like 2v,3v,5v,8v as the diodes and triodes would not function well at high voltages.
(b) In the ancient giant size computers/calculators of 1940s , the communication with the giant’s digital brain was only of one way type . Human engineer sent in numerical data to the giant calculator’s digital brain (CPU).
(3) The communication was only by switching circuits as in a big electrical switching unit . There was no interactive conversation with the machine . The computer’s reactions were indicated by blinking of low illumination light bulbs and readings in the voltmeters and ammeters and some beep-beep sounds.
(4)Though big mathematical problems were solved in millionth of second , the answers to come out on paper tape required one or two days of waiting! The hundred customers who brought their bundles of program cards had to wait for hours to load their data in stages through smaller electric typewriters/ photo-electric machines etc . The answers too came out in serial order. Thus “BATCH PROCESSING” was a silent process. The computer was a silent moody giant not permitting anybody to come near except senior most engineers to operate its logic circuits. Decades passed like this.
(4)
Then truly a technical wonder happened,of course taking a few decades more to take concrete shape and become useful. It happened mainly in technical universities of US and Europe about 70-80 years ago. The sand grain- sized “crystal diode” and the “transistor triode” were invented and almost entirely replaced the 10,000 -15,000 hot glass bulbs (thermionic tubes) of the giant calculators.
Slowly the entire size of computer-calculator became reduced and a new computer was born. After much experimentation and research these machines were standardized by engineers and scientists at universities.
Here we have to clearly realize some basic rules of computer. These rules apply even to most modern computers of the 2020s and also to the “digital phones” which technically come under category of networked computers.
(a)Any electronic computer/calculator is an electrical machine based mainly on mathematical logic .
(b) The radio technology/ telephone technology/ car technology/ airplane technology /medical technology /art technology etc—all such technologies of the different computer-based machines are coveyed to the central controlling computer (the SERVER) through sensors.
(5)
“Software program” closely resemble the working steps of a tough algebra problem and comprises of several perfectly constructed “software instructions”. They are just like the working steps of algebra problem . Each “software instruction” contains one or two “RESERVED WORDS”.
The RESERVED WORDS are actually a powerful combination of several electric/electronic switches . When typed on the computer keyboard these “RESERVED WORDS” activate complicated electric/electronic circuits( of very low voltage electricity).They can start movement of vast data. The actions of RESERVED WORDS are like actions of big trucks carrying heavy parcels from/to a parcel office . Some actions of RESERVED WORDS are as follows.
(a)Data is moved from/to MAIN MEMORY/REGISTERS /ALU etc
( b) Action may be taken to open/close/edit /delete FILES
(c) Bring data into computer or take out data from computer to the monitor screen/magnetic tape( in some old computers)as per commands of CPU.
Thus RESERVED WORDS are like heavy duty trucks of a parcel office in some of their data moving actions.
(6)
The logic/reasoning inside computer’s electronic brain resembles human logic—the human thinking in every day life. The “IAS model” of computer,the world’s standard model architecture for a digital computer ,proves this. (The computer works on very low voltages of less than 10 volts like 2v,3v,5v,8v etc).
We have concept of “files” and “folders”. These are contained in the “SECONDARY MEMORY” ( in the Data Drives like D,E,F drives ) . The “files” and “folders” are similar to the paper note books we use for writing or the printed books which are “read only” type. The colossal data (text/photo/music/ audio/video) is stored in digital form i.e. billions of 0s and 1s in the disc drives . The data can be brought on to computer screen and can be subjected to operations like READ/ WRITE /EDIT .
Only after tiny TRANSISTORS ( one millimeter dimension “doped semiconductor crystals” )came into wide use, the high precision technologies of transistor memory ,printed circuit boards, integrated circuits ,SSI,LSI , VLSI were developed.
Prior to that ,during the period 1950s to 1970s,in the old computers, the “MEMORY”( i.e. recording area) was created with very small magnetized metal rings. The metal rings were fixed in a grid like system of horizontal and vertical hair thin metal wire connections. Even big super computers used magnetic memories . The rings were interlinked with hair thin metal lines and arranged in rows and columns to record data.
After the most advanced and wonderful VLSI technology appeared , tens of millions of “transistors” were created in a single silicon crystals of the size of a shirt button! Such VLSI silicon wafers were created by a costly computer-controlled process .
Microprocessor circuits were (to say in a simple words )etched inside the silicon wafer by computer controlled physical and chemical processes. These tiny chips can contain colossal quantities of data . For example, the bulky Tolstoy novel “War and Peace” can be recorded in the small silicon chip!
(7)
In the IAS type organization of electronic computer ,there are small sized memory units called REGISTERS. They are like highly skilled office assistants with special skills which can do their work (data manipulation ) in millionth –of- second time units. They handle both incoming data and outgoing data. In them data is detained for a brief millionth of second and sent to next REGISTER /ALU( mathematics processor) /MAIN MEMORY.
The inner data processing and mathematical logic parts inside computer are all controlled by CPU the electronic commander-in –chief inside computer .The CPU in turn is controlled by the human operator outside .
The part called “MAIN MEMORY” is exactly like a class room black board where the teacher writes all working steps to solve an algebra problem. SOFTWARE INSTRUCTIONS of a SOFTWARE PROGRAM are typed on the “MAIN MEMORY” BOARD just as working steps of an algebra problem are written by teacher on the black board.
(8)
In a systematic classical way ,after a software program is created on paper ,a FLOW CHART and the ALGORITHM( accurately constructed software instructions ) are prepared .
Flow chart is like an engineering diagram and algorithm is the actual software program written on paper with most accurately constructed software instructions. The software program snould be written only in a IEEE approved SOFTWARE LANGUAGE.
The software program should be typed most accurately on the key board . Even if there is slightest mistake like an extra comma the CPU generates an automatic ERROR MESSAGE and the computer stops working.
The software program is directly typed on keyboard of computer. Inside the computer the software program is converted by a TRANSLATOR SOFTWARE to the 01010101 machine code instantly! The CPU and other logic parts(thinking parts) inside computer can understand only the 01010101 code.
Some model software programs are kept loaded within computer by manufacturers as “LIBRARY FUNCTIONS” to help do the work at extreme speed.
Nowadays GUI type procedures are also loaded by manufacturers . They are created by a new type of software languages. little pictures called ICONS operated through the COMPUTER MOUSE guide the actions of human operator.
We may note that (1) the logic processes in a computer are just like the common sense daily thinking processes in human society(2) it is only the software program that orders the CPU to solve a problem.
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