Most Popular
1500 questions
33
votes
16 answers
History of non-American software/hardware/CS theory development, 1940s-1980s?
I am curious to learn about any developments in computer theory, hardware, and software that took place outside of the United States, in the middle of last century (~1940s-1980s).
I have read 'Where Wizards Stay up Late' (K Hafner and M Lyon; a real…
skytwosea
- 431
- 4
- 5
33
votes
3 answers
Why do PCs boot in 720x400 resolution?
Using my 21" Trinitron OSD, I can see that the resolution at boot is 720x400.
From memory, this weird resolution is extremely uncommon if ever to be seen as a choice on software that supports different resolutions, e.g. 640x400, 640x480 or 800x600…
Eric Cartman
- 6,760
- 5
- 35
- 59
33
votes
8 answers
How exactly did Windows become the OS of the home PC?
As far as I understand it, the whole personal computing revolution that Microsoft Windows did was not entirely by its own design. Is it true that the Windows OS at its core was originally designed to simply be the OS of the terminals of the Windows…
Neil Meyer
- 6,275
- 9
- 29
- 44
33
votes
2 answers
Rescuing data from old audio cassettes
In my recent expeditions to the darkest corners of my garage, I've found a load (there's a pun in there somewhere) of old audio tapes containing Sinclair Spectrum code. These aren't commercial titles, they're record-your-own-code blank tapes from…
KenD
- 1,891
- 1
- 14
- 18
33
votes
19 answers
Was it possible to listen to music and work on old PCs? When was it possible to for the first time?
I was wondering the other day, would it be possible to listen to a midi on a C64 while writing a program or something. I mean it did have a sound chip that would technically just get some new buffers every few seconds, although I imagine the lack of…
user2741831
- 743
- 1
- 6
- 9
33
votes
7 answers
Did the computer mouse always output relative x/y and not absolute?
I am experimenting with a graphics pen and tablet and it got me thinking about the difference between it and my mouse. One huge difference is that the tablet's working area covers the whole screen, so that you can tap on an absolute position. My…
Michael Stachowsky
- 3,151
- 2
- 22
- 31
32
votes
7 answers
Is it legal to download ROM images from shared or internet archives?
Is it generally legal to download older ROM images of commercial software and games for non-commercial use in a retro computing system (emulated or otherwise)?
(Note that this question implies no special knowledge of those ROMs where rightsholders…
user12
32
votes
6 answers
Why does the Z80 include the RLD and RRD instructions?
The Z80 has an instruction RLD, which apparently treats the lower 4 bits in the accumulator and the full 8 bits in (HL) as a twelve bit integer which it then rotates left by 4 bits. The carry flag does not participate in the rotation and the rest of…
Omar and Lorraine
- 38,883
- 14
- 134
- 274
32
votes
4 answers
BBC/Acorn BASIC, what made it so fast?
As I look over old versions of BASIC trying to piece together their history, I come across repeated indications that BBC Basic was really fast. One list puts it running the Ahl benchmark (for all its warts) in 21 seconds, compared to just over 30…
Maury Markowitz
- 19,803
- 1
- 47
- 138
32
votes
12 answers
Dealing with oversized files decades ago? Data transfer in the age of floppy disks
I can imagine the following situation 20 to 40 years ago inside a working office between two colleagues:
"Can I have a copy?"
"Sure, wait a moment....done! [eject] I'll pass that floppy disk onto your table."
"Got it. I also need that other…
neverMind9
- 1,749
- 2
- 14
- 24
32
votes
3 answers
What was the technical reason behind the octal digits used for CompuServe User IDs?
On CompuServe in the 1990's, my ID was "73313, 3443". I still remember it today because it was (seemed) way more important to me than any phone numbers I ever memorized.
According to Wikipedia:
The original CompuServe user IDs consisted of seven…
Brian H
- 60,767
- 20
- 200
- 362
32
votes
6 answers
Why did Commodore sell CPUs to its competitors?
Many of the most popular personal computers and video game consoles of the 1970s and 1980s, including those made by Commodore, Apple, and Atari, used the 6502 CPU (or some close relative, such as the 6507 or 6510). These processors were…
Psychonaut
- 7,133
- 2
- 24
- 54
32
votes
4 answers
Why were early versions of BASIC different?
Most major computer manufacturers/distributors in the 70's and 80's included BASIC with their computers. Some (as answers to this great question have detailed: Why was BASIC built into so many operating systems?) even dropped you into a BASIC…
Aaron
- 2,384
- 2
- 16
- 26
32
votes
1 answer
How does "bit-slip" copy protection work?
Some Apple II 5.25" floppies used a special pattern of bytes that could not be automatically detected by disk copying software. How could the pattern be invisible to disk copiers but detectable by the program itself?
fadden
- 9,040
- 1
- 30
- 84
32
votes
2 answers
Which tools were used to create the C language?
Was the original C compiler written in some old assembly language and now later flex and bison are used instead?
Niklas Rosencrantz
- 1,111
- 8
- 22