Tangentially related: is there a history covering IBM's development of microcomputers? It is clear that the traditional story of the development of the IBM PC leaves out many important details. There the 5100/5110/5120, which goes back to the mid-1970's and reflects the stereotype of IBM. There is also the System/23 DataMaster, where the hardware seems to be the basis of the IBM PC. This seems to go against the traditional story that the IBM PC was some sort of renegade project. (If anything, they appear to be companion projects. The main difference being the DataMaster's focus upon IBM firmware/software.)
I always assumed the reason the PC had an 80x25 display was to allow for emulating the 3270 (80x24 for content and then an extra line at the bottom for the status information) so it's interesting to see that wasn't the case.
> Also, 3270 emulation was not a requirement or goal for the IBM PC, and didn't lead to the 25th line. I would much prefer to have a tidy story where the 3270 led to the PC's display, but unfortunately that's not the case. I talked to two of the original IBM PC engineers to check on this. The said the IBM PC team felt absolutely no need to be compatible with other IBM products. In particular, several features of the PC made 3270 compatibility harder: the use of ASCII instead of EBCDIC, little-endian words, and 10 function keys instead of 12.
Man. I love the design of old terminals, computers, and such.
I am, also, extremely glad that these form factors were abandoned. Having an old terminal, it is possibly the least ergonomic machine I have ever used.
One theory I saw argued the punch card size was the reason for 80x24. But why were punch cards that size? They were designed off of the cards used for the census. Why were the census cards that size? Because they were modeled after the dollar bill size.
I do love thought experiments like this but do believe they’re insatiably unresolvable.
Fascinating article, I really like knowing where the old standards came from.
But I am extremely curious the first picture in the "The IBM 2260 video display terminal" section. All the other pictures show the typical extremely round CRT of the era, but that one is the characteristic cylindrical tube of Trinitrons, a technology released several years later. I am trying to find some information about it to no avail.
No mentioned are the PC terminal apps from BBS era dialup connections that tended to use one of the 80x25 lines as a status bar, leaving 24 lines for the remote display... not to mention avoiding or embracing wrap issues that sometimes left you from using column 80 reliably either.
It's kind of nice to see a lot of resurgence in terminal technologies and remote terminal apps these days... I think AI is letting a lot of people that have been nostalgic pick up projects that would have been too daunting otherwise. Myself included.
Deeply fascinated by these historical threads. It is precisely the various design choices made throughout history that have shaped the computer systems we use today.
The linage can be traced back to Basile Bouchon's paper tape invention in 1725. The article doesn't mention the role of punched cards in The Holocaust, though, which my blog post goes into:
45 comments
https://en.wikipedia.org/wiki/IBM_BASIC#/media/File%3AIBM_Ca... (IBM BASIC screenshot)
[1] https://www.righto.com/2018/01/xerox-alto-zero-day-cracking-...
> Also, 3270 emulation was not a requirement or goal for the IBM PC, and didn't lead to the 25th line. I would much prefer to have a tidy story where the 3270 led to the PC's display, but unfortunately that's not the case. I talked to two of the original IBM PC engineers to check on this. The said the IBM PC team felt absolutely no need to be compatible with other IBM products. In particular, several features of the PC made 3270 compatibility harder: the use of ASCII instead of EBCDIC, little-endian words, and 10 function keys instead of 12.
I am, also, extremely glad that these form factors were abandoned. Having an old terminal, it is possibly the least ergonomic machine I have ever used.
> To avoid these astronomical prices, some computers used the cheaper alternative of shift register memory.
Might be a direction for 2026 too?
I do love thought experiments like this but do believe they’re insatiably unresolvable.
But I am extremely curious the first picture in the "The IBM 2260 video display terminal" section. All the other pictures show the typical extremely round CRT of the era, but that one is the characteristic cylindrical tube of Trinitrons, a technology released several years later. I am trying to find some information about it to no avail.
It's kind of nice to see a lot of resurgence in terminal technologies and remote terminal apps these days... I think AI is letting a lot of people that have been nostalgic pick up projects that would have been too daunting otherwise. Myself included.
https://dave.autonoma.ca/blog/2019/06/06/web-of-knowledge/