It was the years 1973, 1974, ...

In the article on "CONCATISO my first program" I described in broad strokes the characteristics of the computer CID-201-B compatible with the PDP-8 of the DEC company.

Recall that it was 12 bits long, but also only had a 12-bit accumulator register and 1 carry bit.

Machine language instructions were encoded in those 12 bits where sometimes another word was used to access groups of 4096 (12 bits) memory words, and thus be able to access all 32 Kilowords of memory.

As we did not have how to program in text and use an assembly program to convert to binary, we had to encode each instruction by hand, bit by bit, and that led us to know almost by full all the forms of instruction encoding.

The latter allowed us to create programs that modified themselves to be able to run programs with a greater length than the memory we had available, considering that the data in most of the times also had to be in memory since it was cumbersome and slow to read again the punched binary tapes with data, in addition to causing more errors.

In other words, the program changed its own instructions as it evaluated data and calculate results. This is not possible even in the C language, not C++, not C#, not Java, not any other! Not even the programming called "object" comes close to this binary "freedom"!

On the other hand, to set up a program you had to run it manually step by step and observe the lights associated with each bit on the front screen of the computer where "off" meant zero and "on" meant one.

You see, for the machine language programmer of those years, everything was binary !, both the data on tapes or cards, the encoding of instructions, as well as the sight of lights on the front of the computer!

In the years that run, 2020+, for almost 50 years I have not been able to "let go" of imagining everything in binary, be it a video, a photo, Internet browsing, cell phone use, the Internet of things, etc.

Anyway, everything is binary before me! It is lower level than Neo the one from the Matrix "saw" because he "saw" letters and symbols ...

Octavio Báez Hidalgo.

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