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CONCATISO. My first Program. Second part.

By reading the first part you will already have an idea of the computational equipment that the Department of Neurophysiology had back in the years 1972 ... 1973

Now I will tell the other part:

Professor Erwin Roy John, head of the Department of Neurophysiology at New York Medical College, donated to Thalía and her Department an analog "Transient Averaging" computer called "CAT" that was capable of obtaining, from synchronized stimuli and the Electroencephalogram , the so-called Stimulus Evoked Potentials, widely used before and now for the study of man's higher nervous activity.

This CAT had a 5-channel perforated tape printer attached, where the binary code used was proprietary to the manufacturer and therefore could only be used in computers that had tape peripherals with the software that the company provided.

And voila! Here is the problem to solve. I had to make a program to convert the CAT punched tape into another 8-channel punched tape in the 8-bit ISO binary code with parity, which was the one that could be used in the programs that ran on the CID-201-B computer.

First I had to research and document all the CAT binary code, understand the ISO binary code, and develop a solution scheme "fast" enough so that CAT input data could be transferred to ISO output data as it has been known for years "in real time". In other words, it had to synchronize the input, which was faster than the output of the printed tape, to maintain continuous fluidity without losing a single bit.

Keep in mind that input tapes could be tens if not hundreds of meters at times and come on multiple tapes separately, so I couldn't count on 16K of memory! because there were simply more bits than memory to store.

So I had to develop a system of sync buffers and semaphores, as if I were actually building an operating system.

That led me to study UNIX for the first time, in the various magazines where Operating Systems topics appeared, and in DEC documentation that Professor Roy John got me.

By the way, in articles in the "Stories" section of this same site I will comment on how my beginnings in Science were, always linked to my mentors, who as you will read, there were several internationally and conceptually speaking, luckily for me.

At that time I was a student at the Faculty of Mathematics, and "conquered" by another of my mentors, Dr. Pedro Valdés Sosa, I became a worker in the Department of Thalía, first occupying a Work Study Place, and then occupy the Programmer field of work. I was 18, 19, 20 years old at the time ...

Believe that CONCATISO's binary programming was arduous and difficult, especially to set it up so that it did not fail and even that it could be restarted if a tape broke, the power went out, a hardware failure, etc.

But then, when I finished and saw the "little" of the perforated tape with the program, I had no choice but to laugh!

And so far my story of CONCATISO ... thank you very much for your attention.

Octavio Baez Hidalgo.