Hello, World!
I wasn't exactly born yesterday, but this is my first entry on a Blog.
Programmers-in-training (a state which may never end) strive to write a program that sets up a nice window and shows the words "Hello, World" - a great accomlishment. I did the equivalent back when things were much simpler and doing things was thus a bigger accomplishment.
The year was 1970, the computer was a Data General Nova minicomputer (an extinct breed). Programming was done on a Teletype 33, punching a paper tape of machine language, with a set of instructions represented by three-letter mnemonics like LDA and STA. When you had it all typed up you threaded the paper tape through the reader and held your breath while the 33 rattled through it and into the Nova.
I was (and am) a hardware design engineer, but making the computer do something was the ultimate purpose of the exercise. So I wrestled with the arcana of the instruction manual which described one way of getting the thing to cause the Teletype to print a character. Any character.
It turned out that their way of doing it made use of "self-modifying code". That is, you entered a program that said, in effect, "make the Teletype print the chracter immediately after...This One!" Then at the address "This One +1" you entered the intended character into the memory.
I need to explain that "This One" was not how we referred to memory locations. Labels like those takes more programming. I dealt with memory using actual addresses. What did we know then?
So at last there came the moment when my paper tape rattled and I loaded the binary code for the letter "A" into the proper memory location. And pushed the Run switch.
The mute Teletype coughed and smacked an "A" right onto the paper! The feeling was indescribable. Power! Elegance! Infinite possibility! Like someone wrote in a satirical song about the Pope - "he don't even have to use dope".
So - here goes! I've spent my time typing, now it's time to push the Run switch.
Hello, BlogWorld!
11:06:38 PM 
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