Questions tagged [punched-cards]
Punched cards were an early method of digital computer data storage, using cards made of stiff paper with holes punched in specific locations to represent data. They could be punched manually or automatically, were generally read automatically, and commonly held up to a few hundred bytes of data each.
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Was the purported 1968 standard for encoding ASCII on punched cards ever used?
A 1968 Communications of the ACM article describes a proposed USA standard for encoding US ASCII (with a provision to encode all 256 bytes) on punched cards, attempting to keep existing industry ...
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Was bootloading from punch cards possible on System/370 machines?
I have been idly looking into how System 370 works, though mostly at software and VM/370 OS. As a part of the system generation process, one needs to use DMKDDR utility and others. So I was curious ...
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How late were 80-column punched cards relevant?
I'm trying to avoid this being branded as "opinion based", but would be interested in accounts of punched cards being used in "live" environments later than expected.
In my case, ...
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Were punching tools for punch cards with rectangular holes easier to keep sharp than those for round holes?
There is a question here on retrocomputing if round punch card holes where mechanically stiffer:
Were round punchcard holes mechanically stiffer?
I wondered if the reason for the rectangular holes on ...
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Is the substitution "ss" for "ß" on mainframes due to the SS being the largest customer of IBM punched cards outside the USA? [closed]
When I was a child, my German teacher (in a non-German speaking country) told us that the typed form for the letter "ß" in use in mainframes at that time was "ss" instead of "...
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How small a punched card or punched tape batch job could be?
A while ago I read a post about creating the smallest possible ELF executable doing something observable — printing the number 42, for example — which Linux could accept and execute successfuly. The ...
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Was any indentation-sensitive language ever used with a teletype or punch cards?
Most programming languages delimit block structure with punctuation e.g. { ... } or keywords e.g. begin ... end. However, some languages such as Python and Haskell delimit it with indentation (...
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Who introduced the standard 8-bit punched tape, and when?
Who introduced the standard that later became widespread for the 8-bit punch tape, and when? I think the 5-bit tape was an earlier standard.
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How were 18-bit instructions encoded in paper tape?
Early 18-bit computers like PDP-1 were based on 18-bit instruction sets, and used punched paper tape for storage etc. As far as I know paper tape was usually 8 holes, which works nicely with 16-bit ...
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What was the use case for the 96-column punch cards introduced with the IBM System/3?
Shown here at the Computer History Museum site (*)
Not sure when they were introduced but it was before optical scanning (barcodes) was possible / affordable, maybe even before magnetic stripe ...
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What does this 1970s punched-card format mean?
The 1974 Texas Regional Programming Contest (a predecessor of the ICPC) describes an input format:
A room description will be contained on a single card with the format: (1X, I2, 2X, 12 (A1, I2, 2X))....
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How were card sequence numbers typically checked?
Although average punched cards had eighty columns, often only seventy-two were used for characters; the remaining eight were ignored by software. Hence arbitrary metadata could be included with each ...
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Why ASCII paper tape has lower bit punched from the narrow side?
ASCII was presented on paper tape where the lower 5 bits cross sprocket holes as following
While FIELDATA chose the other way
I found placing the higher, flag bits at the narrow side appealing, ...
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Could early computers use existing punch card machines?
In the early decades of the industry, computers used punch cards for data storage and transmission, partly because they were already widely used for pre-computer data processing; indeed, a major ...
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Why were programs entered on punch cards instead of paper tapes?
Dale Fisk's Programming With Punched Cards is a fascinating account of programming in the days of punch cards.
The fundamental dynamic was that early computers did not yet support timesharing.
The ...
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