All Questions

Filter by
Sorted by
Tagged with
0 votes
0 answers
11 views

How do I wait for end-of-frame (VSYNC) on a TRS-80 models 1 and 3?

I've been looking at various documentations, and couldn't find a clear answer. I understand the Model 1 has no interrupt from the video generator, but I'm hoping there's at least a way to busy-wait ...
Cactus's user avatar
  • 2,708
5 votes
2 answers
717 views

Why would email transmission change the 6-char sequence "0rom "?

According to the Ubuntu uuencode manpage: Specifically, email cannot handle binary data and will often even insert a character when the six character sequence "0rom " is seen. Is (or was) ...
TeaRex's user avatar
  • 773
6 votes
2 answers
2k views

Can someone explain the logic behind Pause and Print Screen modifiers?

Firstly, do I have a correct understanding of what these keys do? On the Wikipedia SysRq page, it says that the Alt key must be held down to invoke SysRq. On the BIOS interrupt call page, it says ...
Benjamin Penney's user avatar
8 votes
1 answer
1k views

VT420: How can the five local F keys stop working?

I've got a 1989-issue VT420 terminal I used to use as a secondary console for my Linux machine. After a couple of years, I tried to bring it back to life. After switching it on, the well-known line ...
Neppomuk's user avatar
  • 183
11 votes
3 answers
2k views

What are the minimum system requirements to run GW-BASIC?

In DOSBox 0.74, I can run GWBASIC.EXE without any problem (DOSBox reports 632 KB of free conventional memory). It is GW-BASIC's version 3.10 dated 01-07-1989 with filesize 72576 bytes. On screen it ...
Sep Roland's user avatar
  • 1,165
14 votes
4 answers
2k views

NTSC scan lines used by 8-bit computers

Several computers of the late 70s used a TV set for their display. I'm not talking about the TRS-80, which came with a monitor that was basically a stripped-down black and white TV set, but computers ...
rwallace's user avatar
  • 61.4k
0 votes
1 answer
256 views

What was the RVS key used for on early PCs?

Some Commodore CBM and Sharp MZ-80B keyboards (U.S. version) feature an RVS key, which is linked to an LED on some keyboards (similar to Caps Lock). German CBM keyboards seem to feature a Control key ...
Neppomuk's user avatar
  • 183
1 vote
0 answers
124 views

Apple II sales by sector

Of the American 8-bit personal computers, the Apple II was arguably the most general, in that it sold well to home enthusiasts (Woz's original intended target market), schools (thanks in part to the ...
rwallace's user avatar
  • 61.4k
2 votes
0 answers
110 views

US equivalent of the Microvitec Cub monitor

In the 8-bit computing era, UK schools acquired BBC Micros in a project sponsored by the BBC. The monitor typically used with these was the Microvitec Cub. In the US, there was also a push to put ...
rwallace's user avatar
  • 61.4k
10 votes
1 answer
3k views

Is there any DOS game before Quake era (1996) that makes heavy use of the FPU?

Quake was one of the earliest DOS games to show most gamers the importance of having a fast FPU to play with. Were there any other games (probably 3D) before Quake that started using the FPU? For ...
tigrou's user avatar
  • 467
9 votes
4 answers
1k views

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 ...
Leo B.'s user avatar
  • 19.3k
3 votes
0 answers
92 views

Was the Atari 800 expansion port hidden because of RF emission? [duplicate]

I just stumbled on a curious detail about the Atari 8-bit machines that I had not known about: https://forums.atariage.com/topic/133652-400800-expansion-port-pinouts/ I've seen questions about the ...
rwallace's user avatar
  • 61.4k
10 votes
4 answers
2k views

Why did the Amiga 2000 only produce grayscale on its composite output?

The Amiga 1000, 2000, 500, 1200, and 600 all had composite video output ports in addition to their preferred RGB connectors. While I know that the A1000 will produce color output over the composite ...
bjb's user avatar
  • 16.4k
9 votes
5 answers
4k views

Did ROM chips jump from 8K to 32K?

This is a question about mask ROM (not EPROM) chips of the 8-bit era. The size of DRAM chips increased by factors of 4, so there were 4kbit chips, then 16kbit, 64kbit, 256kbit etc. The natural width ...
rwallace's user avatar
  • 61.4k
14 votes
1 answer
2k views

I cleaned the grease off an old floppy drive’s motor; do I need to lubricate it?

I have a Sony HD 3.5″ floppy drive. It isn't reading properly and IMD shows the rpm to be 150-200. I dismantled the drive and there was a sticky ‘goo’ on the bottom of the inner ring that sits inside ...
squelch41's user avatar
  • 141
8 votes
2 answers
1k views

How does the 8086 jump instruction work when the target address overflows?

For educational purposes, I'm developing my own software emulator for the 8086 microprocessor with VGA/MCGA support. Although it's far from complete, it's advanced enough to start using a BIOS (though ...
ExecAssa's user avatar
5 votes
2 answers
403 views

How to read/write word from DECtape on SIMH?

I am learning programming assembly for PDP-4 using SINH simulator. I stuck at understanding how tape drives work. I want to read one word from DECtape 550 unit 1 but I don't know how. I'm learning PDP ...
Codesynth's user avatar
6 votes
3 answers
489 views

Cray quote about supercomputers... a megaflop needs a megaword or similar?

I'm trying to find a quote that I'm 90% certain was attributed to Cray. It was to the effect that a computer that processes at a rate of one megaflop also needed a megaword of memory and [something ...
Maury Markowitz's user avatar
15 votes
1 answer
3k views

What's the story behind the "mysterious" 486DX3?

As I was skimming through an old MS-DOS game's README, I stumbled upon this: Therefore, we reccomend a newer 486-100 or better, preferably with a large external cache. Best performance will result ...
aybe's user avatar
  • 7,092
9 votes
5 answers
3k views

Windows War Strategy Game

I remember when I was younger playing a WWII (possibly WWI) strategy game, that I'm pretty sure was for Windows 3.1 but it may have been an early Win'95 game, and a big chunk of the main screen was a ...
Matt Lacey's user avatar
  • 2,320
3 votes
0 answers
230 views

What is the “data file browser” that appears in the film “Segreto di stato” (1995)?

From the movie "Segreto di stato" (1995) at minute 01:29
elbarna's user avatar
  • 2,169
3 votes
3 answers
744 views

ZenithZ89 System Font

What is the font (ttf name ideally) used in the ZenithZ89 System Font? (This is a retro question - if one were to emulate it using currently available fonts, which would be used?)
ina's user avatar
  • 131
6 votes
1 answer
238 views

Is there a PCMCIA Bluetooth card that would work in a Psion Series 7?

I am looking for a PCMCIA card that would add a Bluetooth serial port to my Psion Series 7. The Psion Series 7 PCMCIA port has several limitations: only has drivers for serial port doesn't have ...
Mark Williams's user avatar
0 votes
1 answer
210 views

Commodore "B-series" BASIC?

I'm implementing error handling, TRAP/ON ERROR and RESUME, in my parser. As the C64 is arguably as close as one might get to "a standard", I chose to use those error numbers in my code as ...
Maury Markowitz's user avatar
11 votes
1 answer
457 views

A mixed first-person 3D/top-down 2D game for DOS, probably from the 1990s, about a boy protagonist escaping from being abducted by aliens

The way I remember it, I first played this game on a CD (sadly, I do not recall the name) that contained dozens of DOS games. I think that this was in 1995, but I am not sure. The following is an ...
Micheal Gignac's user avatar
6 votes
1 answer
863 views

How to mass-reset the protected flag in classic MacOS

I have a library of 123k Mac (mostly System 7 and older) related files in 32k folders on a 40GiB volume on a file server running Novell Netware 3.12 from 1993 on VMware ESXi. Netware has excellent AFP ...
PoC's user avatar
  • 1,282
3 votes
1 answer
2k views

How does Quake 1 access video memory in software mode? [closed]

I have WinQuake.exe game file which I compiled myself from source. In software mode (without DirectX/OpenGL), what function is used to access video memory? I know, for example, the DrawDibDraw WinAPI ...
black4's user avatar
  • 147
0 votes
1 answer
392 views

What does this triangle rasterization code do? What does it use a “depth cueing table” for? [closed]

Who can explain to me what is the depthq_table, how is it built, how the function works gtmap_persp32_fp, how arranged perspective correction every 32 pixels in this function? That is, as I understand ...
black4's user avatar
  • 147
4 votes
3 answers
817 views

Sony PVM (PVM-14M1J, NTSC-J) Displaying the Wrong Colors

Edits I have accidentally used the word composite over component, but after testing it with an RGB cable and an S-video cable, the results are the same. I've been told to mention that my PVM is NTSC-...
Tai Alt's user avatar
  • 73
1 vote
1 answer
115 views

USB CD-ROM drive not working with Fujitsu Stylistic 3400

I had a Fujitsu Stylistic 3400 that was lying upstairs for a very long time. One day, I decided to take it downstairs and try using it with the LG portable DVD drive I got from my dad. I decided to ...
Hamh2t2 The Computer Guy's user avatar
6 votes
1 answer
509 views

In the 1999 movie The Matrix, what is the news reader software that is being used?

The above is a screenshot from the film. The application icons seem reminiscent of the Tkinter Perl applications from the late 2000s, which would suggest a Gtk1 or Gtk2 icon set(?) What is this ...
tetris11's user avatar
  • 163
2 votes
0 answers
222 views

How to connect old Nokia 3220 phone to a modern computer? Or login to Drive on the phone? [to transfer data from phone]

I have an old Nokia 3220 mobile, which has an "Internet" app built-in. The phone does not have Bluetooth or Wi-Fi support. Now, there are some files on the phone that I would like to keep (...
koustav_ch's user avatar
24 votes
11 answers
9k views

Why did XML lose out to XHTML, then HTML 5, on the web?

I started my web design career back in the late 90s, and at that time web page technologies seemed to be in a state of flux. In particular, I remember a transitional period prior to widespread ...
Noel Whitemore's user avatar
17 votes
1 answer
595 views

Why did Acorn use LF+CR instead of CR+LF as a line ending?

The most common conventions for indicating newline nowadays are CR+LF (most famously Windows, but also the Internet standard) and bare LF (Unix and Unix-like systems). Historically there have been ...
Simon Kissane's user avatar
9 votes
2 answers
2k views

Why does the BRK instruction set the B flag?

On the 6502, the brk instruction is a software interrupt. Like any other interrupt, it pushes the status word to the stack and then the program counter, before transferring control to an interrupt ...
Omar and Lorraine's user avatar
4 votes
1 answer
205 views

Coronet and Coronet II benchmarks?

I'm reading about the IBM ASC project, and I see repeated references to a benchmark known as Coronet and/or Coronet II. Does anyone know what this did?
Maury Markowitz's user avatar
9 votes
2 answers
347 views

What floating point libraries were written to meet the IEEE 754 standard before it was accepted in 1985?

The IEEE 754 floating point arithmetic working group began in 1977 and was formally accepted in 1985. One of the original driving factors of the standard itself was Intel who wanted a standard to go ...
Adam Hyland's user avatar
11 votes
0 answers
370 views

When was the asterisk first used for "unsaved changes" and why?

The asterisk itself has been around as a symbol since literally (pun intended) before the earliest writing systems. Among its many uses, in some user interfaces it denotes unsaved changes to a file or ...
TypeIA's user avatar
  • 211
4 votes
0 answers
144 views

How much does Micro-80 BASIC resemble Microsoft BASIC?

The first DIY Soviet home computer Micro-80 and its successor Radio-86RK had an implementation of BASIC available (albeit not in ROM, but as an loadable binary). A page from which the link is taken ...
Leo B.'s user avatar
  • 19.3k
3 votes
0 answers
87 views

What is the output of the Supersoft Diagnostics II v1.2 on an Intel 8080?

Supersoft Diagnostics II is a program to test 8080 and Z80 CPUs, as mentioned in this answer, and questions here and here. As well as sources mentioned in those posts, the program binary and a ...
cjs's user avatar
  • 26.6k
2 votes
3 answers
779 views

Understanding the Need for Positive Sync Polarities in Sony PVM Monitors

Understanding the Need for Positive Sync Polarities in Sony PVM Monitors Note: This post has been edited several times during its lifetime, and some questions may have already been answered. I'm in ...
Tai Alt's user avatar
  • 73
5 votes
1 answer
557 views

Does the Intel 8080 ANI instruction clear or update the half-carry?

It's known and documented that on the Intel 8080 most logical operations (including all OR and XOR operations) clear the half-carry (auxiliary carry) flag. A known exception is the ANA instruction, ...
cjs's user avatar
  • 26.6k
9 votes
2 answers
499 views

What elements of the MOS 6502 did it copy from the Motorola 6800?

It is not uncommon for microprocessor system designers to copy elements of design from other microprocessor systems; the Z80, extensively copying design elements of the 8080, is a notable example. ...
cjs's user avatar
  • 26.6k
3 votes
0 answers
140 views

Hierarchical/navigational database engine available on RSX-11M

Around 1988-1990 I worked for a company that was using an old RSX-11M system to host an ERP application. The application used a third-party database product of which I am trying to recall the name. ...
Anthony X's user avatar
  • 421
7 votes
1 answer
234 views

Analog to PWM for Analog input on Retro game controller?

On the NES and SNES a common feature on 3rd party controllers was "Slow-motion". It worked by repeatedly pressing and releasing the start button. Because many games simply froze gameplay ...
John Battelle's user avatar
6 votes
1 answer
514 views

In the RL02 disk system, why does the “read” command take CHS coordinates, when there is also a separate “seek” command?

Why is it that the RL02 disk system of the PDP11 has a seek command yet the read command also knows where to read from as the cylinder/head/sector are given via the 'DAR' register? http://www....
Folkert van Heusden's user avatar
17 votes
2 answers
3k views

Identify this children's Commodore 64 book

I'm trying to remember the title of a book on Commodore 64 programming that I had as a child. Here is what I remember about it: Published some time between 1982 and 1985 and sold in Canada. The ...
Psychonaut's user avatar
  • 7,551
0 votes
2 answers
190 views

ASM as a DSL of a HLL? [closed]

There used to be a lot of discussion as regards embedding DSLs (Domain Specific Languages) into high-level languages (HLLs). The only example, where this is possible, I know of, is c++ and I had ...
user1095108's user avatar
13 votes
3 answers
1k views

What are some tracing disassemblers for the Z80

What are some some tracing disassemblers for the Z80? I.e., disassemblers that will trace through the code and disassemble as instructions only the areas it traces through, leaving the rest as data. (...
cjs's user avatar
  • 26.6k
5 votes
4 answers
280 views

First free and open source assembler and linker for i386 targeting and running on Win32

I'm looking for the first free and open source assembler and linker for i386 targeting and running on Win32. My requirements are: It has to be able to build a Win32 PE .exe from assembly source, the ...
pts's user avatar
  • 2,013

15 30 50 per page
1
2 3 4 5
121