• Please review our updated Terms and Rules here

Favorite Retro Computer Programming Environment

Punched cards have been around for a long time. They were used by the British during WWII on the Colossus for Ultra intercepts, as an example. The first punched tape that I ever used was of the then, new, Mylar variety, on the Varian 620i (1974-75).
 
barythrin said:
Yeah, I realize they are different eras (punch cards and GUI interfaces) but was just curious. I was thinking a low resolution point and click punch card where you could punch it and it would then send the output to a keypunch, or perhaps write your program and it would convert it to punch card format and punch the cards for you. I'm assuming the keypunch systems were manual and the user actually wrote either code or just said what holes (or physically set the bits up/down and it them punched a hole in the card)?. I guess I should look for some videos of keypunches and punch cards lol. Obviously before my time so all I've ever seen are punched cards, never the process or any improvements on what it was like punching them.
Click to expand...
Good idea! Don't forget that cards and paper tape preceded any kind of video display; no idea what you mean by a "point and click punch card where you could punch it and it would then send the output to a keypunch"...

No, you didn't punch individual holes; there were various codes and formats, but however they were punched and in whichever format, cards (and tape) were punched a column at a time, with the pattern of holes in that column usually representing a letter/number/symbol although there were a few formats that "stacked" two (or more?) characters in the same column. Incidentally, there were 'edge punched cards' that were cards with tape perforations punched along one edge.

They were usually punched by an operator using an electr(on)ic keypunch (or teletype equivalent if it was tape) or automatically from a computer, although there were completely manual punches as well for one-off or very low volume needs.

An interesting topic for some Googling for sure...
 
Punched cards are far older than computers. See this Jacquard loom, circa 1801, for example:

device.jpg


But punched paper tape is marginally older than punched cards. This Bouchon loom is from 1725:

Basile_Bouchons_loom.jpg


Lest you think that Jacquard had the first punched-card loom, it's worth noting that a co-worker of Bouchon, Falcon, substituted punched cards for the paper tape (allowed easier editing) in 1726. These early machines met with huge resistance from the hand-loom weavers for obvious reasons. The reason that Jacquard is important is that Babbage knew about Jacquard and his looms and even owned a Jacquard-loom-woven portrait of Jacquard.

And we know how important Charles Babbage was...

The advantage of punched cards over punched paper tape should be obvious. Namely, a sequence is very easy to edit--just replace the cards that need changing; a deck of cards is easy to repair if damaged; a card can represent a block of information, be it a line of code or a customer account or census data and be easily sorted and searched mechanically. And cards are generally very robust.
 
Last edited:
You must log in or register to reply here.
Back
Top