2010: 50 years of India's first digital computer

The TIFRAC, a first-generation main-frame computer developed for scientific computations, was commissioned on February 22, 1960, at the Tata Institute of Fundamental Research (TIFR), Mumbai, making India the first country in Asia and Japan to have built such a machine.

The machine was christened 'TIFRAC' (Tata Institute of Fundamental Research Automatic Calculator) by the then Prime Minister Jawaharlal Nehru when he visited TIFR on 15 January, 1962, according to documents obtained from the TIFR Archive. Before developing a digital computer, Indian scientists had also built an analogue computer. This was developed at the Indian Statistical Institute (ISI), Kolkata.

The main assembly of TIFRAC, which had vacuum tubes was housed in a massive steel rack measuring 18 ft X 2.5 ft X 8 ft. It was fabricated from modules of 4 ft X 2.5 ft X 8 ft, according to an article written by project head, the late Prof R Narasimhan.

Each module had steel doors on either side for accessing the circuits, said the article, written in 1960 and reprinted in a journal of the Indian Institute of Science in 2008. It was obtained by PTI through the TIFR Library. A manual console served as the input/output control unit of the computer that had a ferrite core memory of just 1024 words.

This amounted to one KB of RAM of a Computer Word of 40 bit width. Today a typical PC has one GB of RAM of Computer Word of 32 bit. Input to the TIFRAC was by means of a punched paper tape and the output was either printed out directly or punched on paper tape, Narasimhan's article said.

A cathode ray tube display system was developed to serve as an auxiliary output to the computer for analogue and digital display of both graphs and alpha-numeric symbols, the article said. In contrast, today's PC has a high quality monitor, keyboard and mouse for input and output, plus a printer.

The software of TIFRAC was developed by Narasimhan and K S Kane. These were written in a series of commands of 1's and 0's in comparison to an Operating System of today which has a host of applications with graphic interfaces, enabling almost anybody to use a PC with ease.

Though fundamental units of a computer remained the same, the backup device has long changed from drum to tape to high speed cartridge and also CDs and DVDs for permanent storage. High volume hard disks also work as regular back up storage devices, said Sugata Sanyal, professor of computer science, TIFR.

The hardware designer team included B K Basu, K L Bhakhru, M M Farooqui, D S Kamat, P V S Rao, T R N Rao, C V Sriniwasan, and S P Srivastava assisted by D F Cooper, M M Dosabhai, B B Kalia, R Y N Iyengar, R N Neogi, and V K Joglekar. The software team included R Narasimhan, K S Kane, C N Kumar, V S N Reddy, and B G
Mythili.

"Before the main machine, we first developed a workable pilot model which became ready in September, 1956. The pilot machine was shown to the faculty that approved the main project and Rs seven lakh was sanctioned for it," M M Dosabhai told reporters.

"Computer science and technology were in their infancy at the time when we started our effort. Our task involved putting together several tens of thousands of individual components - resistors, capacitors, wires and vacuum tubes," said P V S Rao.

"I can still recall when all the electronics – the arithmetic, memory, control, and display units of our system operated in synchrony for the first time. Our handiwork was actually working as a computer," Rao said. The designing of the full scale machine began in early 1957 and its final assembly was completed in February 1959. However, due to lack of air-conditioning facilities, the work had to be suspended till the end of 1959.

The actual testing began in mid-November that year with an auxiliary air-conditioning system and the computer was commissioned in the third week of February 1960, Narasimhan's article said. K S Kane said, "TIFRAC was a good starting point to use computers for academic purposes. It remained in operation till mid 1964 and its users included scientists of Cosmic Ray section of the TIFR, University of Madras, Central Water and Power Research and others."

According to V K Joglekar, the development of TIFRAC helped understanding the infrastructural needs and personnel requirement necessary for establishing a computer industry in India. She said, it also created a pool of computer technology experts who ultimately helped establish organisations like CMC and ECIL.