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Marvel Comics BASIC games from the 1980s?

When I was a young kid in the mid-1980s, I attended a computer camp intended to introduce kids to BASIC. One of the things we typically did was to transcribe BASIC programs from paper copies. I ...
jamesdlin's user avatar
  • 141
25 votes
3 answers
18k views

Since when does Windows support forward slash as path separator?

Historically, Windows used CR/LF and backslash, first for new lines, second for path separator. But it turns out that it supports forward slashes as well: Note that Windows supports either the ...
aybe's user avatar
  • 6,620
11 votes
2 answers
1k views

Why did the VAX compatibility mode not implement the MARK instruction?

This question was inspired by an older question about the MARK instruction which recently bubbled up to the top of the active pile. The VAX-11/780 and several follow-on VAXen implemented a PDP-11 ...
dave's user avatar
  • 35.2k
4 votes
2 answers
2k views

Gameboy Key Input Causes Crash

I made a Key Tester using the STDIO header included with GBDK. It works... Until it doesn't. All the keys register and print to the screen, except the Left(5) and Right(4) Directional Keys, which ...
OPM eStudio's user avatar
5 votes
1 answer
319 views

Why is the start address in the PDP-11/23(+) micro-ODT a 18-bit address?

The KDF11 processors (as used in the PDP-11/23 and PDP-11/23+) contain an 18-bit implementation of ODT, called Micro-ODT. Micronote 058 states that the standard start address for a large (18- or 22-...
JosF's user avatar
  • 153
-4 votes
1 answer
186 views

Why was Teletype Corporation's Model 33 ASR console always mounted on a metal stand? [duplicate]

Why are all complete Teletype Corporation Model 33 ASR shown mounted on a dedicated metal stand?
PDP11's user avatar
  • 619
10 votes
2 answers
3k views

Digitally stored data world total history?

Storage clusters now reach 1TiB/s speed (cern, ceph) so I was wondering: when did the world total stored digital data reach a terabyte? Was there research on the topic? The System/360 in 1964 shipped ...
chx's user avatar
  • 913
2 votes
0 answers
164 views

What to do when Apple IIc displays 'check disk drive' alert [closed]

I have an Apple IIc ROM version 3, with original program discs. A few years ago I dusted it off for fun. I found online a suggested way to network it with a PC. What I remember from a few years ago ...
jesto's user avatar
  • 21
14 votes
1 answer
651 views

Why does this Soviet floppy controller have two windows in the chip package?

This is a picture of the KR1818VG93, a Soviet clone of the WD1793 floppy controller. It was used in some Spectrum clones: (source) What are the two windows in the chip package for? They appear to ...
user1908704's user avatar
19 votes
3 answers
4k views

How fast was ARPANET?

I've heard that the first time a message was sent through it was "lo" since the SDS 940 crashed before the full message of "login" was able to be sent through. However, I have been ...
jay's user avatar
  • 293
7 votes
3 answers
1k views

Were there any PCs where you could switch Turbo Mode via the keyboard?

All the PCs I have personally used or encountered which had a "Turbo Mode" (clock frequency switch, with frequencies in the 5-25MHz range) did this via a hardware button similar to the reset ...
dirkt's user avatar
  • 27k
4 votes
3 answers
3k views

Blue-Green Software Mascot

I recall seeing a mascot for some sort of computer platform or program. I've seen images many times, but am now struggling to find it. Here are the details I can remember: I think it was a 1990s ...
rightbrace's user avatar
1 vote
0 answers
163 views

What is the keyboard combination for turbo on Prolinea 3/25?

I have a Compaq Prolinea 3/25zs (BIOS 08/03/92 386C)and suspect it can be switched between 25 MHz and some lower speed. There's a BIOS setting for System Power-on Speed, "Auto" or "High&...
eesz34's user avatar
  • 561
0 votes
1 answer
223 views

Finding a vertical scrolling arcade game from the 90´s

The game I'm looking for had the possibility for two players controlling a red or blue fighter jet. The style reminds of the "Raiden" games on arcade. The only specific I remember is that ...
Terje's user avatar
  • 19
5 votes
1 answer
292 views

How to use dd command to write a PC booter floppy image to a USB flash drive?

I have some PC booter images from new homebrew games by this Japanese developer: http://inufuto.web.fc2.com/8bit/ As I know, those images have a 360k size, and are self-bootable by the old IBM PC (...
Igor Peruchi's user avatar
14 votes
1 answer
3k views

How did an old mouse detect if it was connected to PS/2 or USB port?

Prompted by this earlier question about USB-to-PS2 adapters, in which the answer is that the mouse figures out what it is connected to, the question arises: how do it know?
dave's user avatar
  • 35.2k
0 votes
2 answers
208 views

Getting DDR 400Mhz ram to run at 533Mhz [closed]

Someone at the computer enthusiasts site "yelled" at me that this question belongs here. I got my Dell Dimension 2400 to run at a FSB of 133Mhz! Yes, I plan to make a more in depth tutorial. ...
qwerty keyboard's user avatar
39 votes
3 answers
8k views

How did early green PS/2 to USB mouse adapters work?

I remember when USB mouses came out those green PS/2 to USB adapters were around. (I cannot remember to have seen a purple keyboard adapter doing the same. But that doesn't mean anything.) I always ...
zomega's user avatar
  • 5,352
2 votes
1 answer
317 views

Could the BBC Micro have used 8 additional colours in mode 2 instead of flashing colours?

As a teenager with a BBC Micro in the 1980s, I would often write small graphical programs, and - like many programmers of the day - I was very familiar with all the modes and the colours associated ...
Plunder Bunny's user avatar
5 votes
1 answer
502 views

Reverse engineering an old 40-pin connector

I found a 40 pin connector on the side of one of my old electric typewriters. There is zero documentation of this plug online or in the owner's manual, and I want to figure out what exactly it can do. ...
UberRix's user avatar
  • 51
4 votes
1 answer
191 views

8251A UART outputs unexpected data

I am currently prototyping an Intel 8088 system (Maximum Mode) on a breadboard. Later I want to move to custom designed PCB. To get some input and output, I wanted to use the 8251A chip. I have two ...
x95's user avatar
  • 151
3 votes
2 answers
277 views

How to use BASIC-86 from Microsoft with SCP 8086 simulator

After the exciting news that a very early version of 86-DOS (0.11) from Seattle Computer Products was found I played a bit with the simh / Altair Z80 simulator to run the 86-DOS image and was ...
leon22's user avatar
  • 354
2 votes
0 answers
165 views

HP 2000 Time Sharing BASIC Versions

I used HP 2000F TSB in the mid 1970's during my school years - via a remote dial-up teletype. I've now installed and have working the simh 2000F and Access systems on my computer. I have also ...
hptsb's user avatar
  • 41
5 votes
1 answer
179 views

Does the PDP-8/E service an interrupt after any instruction, or after instructions not referencing memory only?

While researching this answer about incrementing the program counter, I found something I thought was a little odd in the FETCH state flow diagram, which is figure 3-8 of the PDP-8/E & PDP-8/M &...
Omar and Lorraine's user avatar
8 votes
1 answer
679 views

Why would a 720k (DSQD/96tpi) 5.25" floppy disk be read as 360k?

I'm backing up some old floppy disks, some of which are Double Side Quad Density 96tpi Soft-Sectored disks, which I understand to have capacities of 720KB. When I read the disks (in a 1.2MB drive) ...
Synthetic Ascension's user avatar
8 votes
1 answer
467 views

PDP-8 conditional skip and 2-word instructions

PDP-8 heavily relied on conditional skips: instructions that under some circumstances would skip the following instruction. Among them are, for example: ISZ SZA/SNA/etc. group of insns many IO insns ...
lvd's user avatar
  • 10.4k
7 votes
1 answer
447 views

How to treat an old PC

I have an old IBM PS/2 30/286, now sitting for a while on one of my desks. I'm a bit afraid that it will stop working sooner or later, so what's the best way to keep it 'alive' ? I fire it up every ...
Tommylee2k's user avatar
10 votes
1 answer
1k views

PDP-8 floating point numbers

I'm trying to find a single clear statement of the limits to the numbers represented in the PDP-8's three-word format. I found the original documents on this, but they are, ahem, not exactly ...
Maury Markowitz's user avatar
4 votes
4 answers
1k views

The move to protected mode on x86 [closed]

When I learned programming, the programmer of the CPU had direct memory access. That is, the Z80, the 8086/8088, 6502, and so on. I don't know of any real use of the 186, but at least the 286 ...
ABM K's user avatar
  • 472
2 votes
0 answers
177 views

Monochrome ISA graphics adapter with the smallest footprint [closed]

I am designing an x86 retro computer, and I can't find a suitable 8-bit ISA graphics adapter for it. I don't need much in terms of graphics: mostly I need a text mode in black and white, some kind of ...
tpimh's user avatar
  • 406
2 votes
0 answers
100 views

HORI HPS-83 ZeroForce Steering Wheel - are there any resources about the hardware

I obtained a PSX controller from title. Deal is, that I'm interested in gaming history, backstory etc and thus I'm curious about the wheel, how it came to being, how was it advertised, had it any ...
M'cin's user avatar
  • 21
6 votes
1 answer
485 views

How did AMD Am386 and Am486 outperform Intel's version of the same microprocessors?

This question is related to a previous one that has been asked here before (How did AMD's 386 and 486 perform like Intel's newer generation?) My question is-two fold: a) When AMD "...
interested22's user avatar
3 votes
2 answers
430 views

Why does my MZ executable's BSS inflate by ~1,5KB after linking fopen() with MSC?

For a game reversing project, I am trying to undo linking with the C library performed by the MSC 5.1 C compiler+linker. To that end, I have created a simple executable that does nothing except ...
neuviemeporte's user avatar
6 votes
1 answer
282 views

Replacement RDRAM chips for my Sony PS2

Oh yeah, just my luck, while I have my PS2 open to replace the clock battery one the magnet I use to hold the screws sticks to the RF shielding, comes off, and lands on the memory chips, cracking one ...
qwerty keyboard's user avatar
4 votes
1 answer
740 views

Why didn't the CD come with a caddy by default? [closed]

I've had plenty of scratched disks over the years, even scratched many myself when I was a kid. But it's my scratched copy of Call of Duty World at War for the PS3 that really makes me ask this ...
qwerty keyboard's user avatar
8 votes
0 answers
235 views

What were the licensing terms for The Hobbit? [closed]

The Hobbit was a 1982 illustrated text adventure game released initially on the Spectrum, based on the Tolkien novel of the same name. According to https://www.filfre.net/2012/11/the-hobbit/ Unlike ...
rwallace's user avatar
  • 60.2k
8 votes
1 answer
581 views

Size-optimization of a 256-byte "LDIR" adapter

I'm working on tweaking ABC-800 BASIC II machine code, and there's a routine there that does a "256-byte" equivalent of LDIR. B is not used, C=0 transfers 256 bytes, C=1 transfers 1 byte, ...
Kuba hasn't forgotten Monica's user avatar
19 votes
10 answers
7k views

When did computer manuals and books start using monospace fonts for code, and why?

At least through the early 1980s, the source code in non typewritten computer manuals and books was usually typeset using proportional fonts, sometimes with syntax highlighting such as keywords in ...
Paolo Amoroso's user avatar
24 votes
1 answer
4k views

What did SULFNBK.EXE actually do?

SULFNBK.EXE is an executable file that came with Windows 98 and Millennium, and is known for sporting a pretty… interesting icon in the former: It has also become pretty infamous for being subject to ...
user3840170's user avatar
  • 22.8k
7 votes
2 answers
940 views

How were sprites handled on the IIgs?

The Apple II series including the IIgs did not have hardware sprite handling, though the IIgs did have high resolution graphics (compared to other Apple II machines). However people did manage to ...
Michael Shopsin's user avatar
6 votes
0 answers
451 views

Does the Game Boy version of Tetris have any crashing problems like the NES version?

Apparently history has been made when a skilled gamer manually crashed the NES Tetris at 1511 lines With rolling pushing NES Tetris games way longer than the original developers ever imagined it ...
Machavity's user avatar
  • 515
7 votes
5 answers
2k views

Spectrum DIY upgrade to 48K

The ZX Spectrum was initially sold in 16 and 48K versions. Every owner of the former version who continued using it, inevitably ended up wanting the upgrade to the latter. (I get the impression it ...
rwallace's user avatar
  • 60.2k
5 votes
3 answers
1k views

Why doesn't the Acorn Electron use fast page mode?

The Acorn Electron, trying to provide 32K of RAM as cheaply as possible, uses four 64k chips, for a 4-bit data bus. Obviously, this involves trading away some performance. (In all the following ...
rwallace's user avatar
  • 60.2k
12 votes
1 answer
3k views

In Super Mario Bros., how can I start a simultaneous multiplayer game?

I happened to receive an old NES with Super Mario Bros. My kids pointed out that there's a two-player mode where both Mario and Luigi play at the same time. Does anybody know how to get it going? FWIW,...
AVIDeveloper's user avatar
8 votes
2 answers
2k views

What does Spectrum BASIC have that ZX81 lacks?

The Sinclair ZX81 has 8K BASIC interpreter ROM; the Spectrum has 16K. What extra features does the Spectrum put in the extra 8K? The most obvious thing is commands for color graphics, which are absent ...
rwallace's user avatar
  • 60.2k
4 votes
1 answer
399 views

How can I restore a TapeDisk backup on a modern PC?

Back in the 1990s and a bit later I used DAT DDS tape for backups to a SCSI tape drive. The software was "TapeDisk" which allowed the DDS tape to appear as a HD. I'm trying to get some files ...
A J's user avatar
  • 41
13 votes
4 answers
3k views

What prompted Nintendo to use SRAM rather than DRAM for the PPU memory on the Famicom?

The TMS9918 video controller which came out in the 1970s is designed around the use of DRAM for video memory--typically a bank of 16Kx8. Not only was DRAM vastly cheaper than SRAM, but it also ...
supercat's user avatar
  • 35.7k
8 votes
1 answer
987 views

Did any 8-bit computers use 16kx4 RAM chips?

An 8-bit computer wanting 64K of RAM, could most straightforwardly use eight 64kx1 DRAM chips (64kbit, 1 data line). The Commodore 64 initially did this, but in the mid-80s, the cost-reduced redesign ...
rwallace's user avatar
  • 60.2k
2 votes
1 answer
394 views

What were 3dfx's future plans for their Glide API before it was phased out? [closed]

The end of 3dfx in December 2000 also meant the end of the Glide API for new games. But does anyone, perhaps former 3dfx employees, know what the future of the Glide API was planned if 3dfx had ...
Coder's user avatar
  • 1,009
4 votes
2 answers
275 views

Asus eeePC 1000H with lubuntu: upgrade possible? [closed]

My son was cleaning out his room and found my eeePC he borrowed a long time ago :) So I am trying to get it to do something useful, and found it runs on lUbuntu 18.04 LTS This model was originally ...
ABM K's user avatar
  • 472

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