All Questions

This is an essentially trivial question, but anyway: several operating systems have a command to display a specified text string on the terminal, or standard out, or whatever (depends on system to ...

I have a strange desire to make an imaginary competitor to the Atari 800 (6502 + different custom chips). As far as I can see people are mostly interested in making "my childhood computer, but with ...

I have this monitor, which I think is a Commodore 64 monitor. I would like to connect it to a pc. Anyone know how to convert VGA or HDMI to this connector format? I've tried searching, but so far I'...

I'm looking over what little I can find on the 8502, and from what I can see it appears to be a 2 MHz version of the 6510 with an extra I/O pin. Much ado about the speed, but the Atari's 6502B's were ...

I had always assumed that EMM386.EXE was responsible for managing the Upper Memory Blocks - UMBs - the memory space between 640KiB and 1MiB in real mode x86. For example, on MS-DOS 6.22, help emm386....

I play around with emulators, and would love to go back to my roots, with physical ZX81, BBC Micro, Amiga, etc. Unfortunately, those all require a TV as output. I suppose that I could buy a cheap one ...

I've read that the usual way to execute code on the N64 is to use DMA to copy it from ROM into RAM, and then run from RAM. However, it seems that the contents of the ROM are directly visible to the ...

Is there a software method of disabling memory refresh on the Z80? Or would it be acceptable to create a hardware method of disabling the address bus during the refresh cycle? If I switch off the ...

For those of you who are unaware, professional speedrunner Trent Hall discovered a now banned strategy in Goldeneye 007. This strategy (called Trent's Circuit Board Strategy) consisted of plugging a ...

Poking about in early issues of Dr Dobbs' Journal (the journal of the People's Computer Company, or PCC) I came across a listing for BASIC games available on tape. Many of these are widespread, but a ...

I'm reviewing the historical original ASCII standard. There are many control characters. Does anyone know the history of them and where finite state machines that made use of them may be documented? ...

The original NES has a label printed onto it that the device would not "cause harmful interference". Why would they write that? Did people think the NES might be dangerous? Is this some kind of legal ...

Is there such thing as a para-emulation? Like para-virtualization but for emulation? If so, where could I find a website that describes it?

While trying to use a "modern" sound card (an Aztech Sound Galaxy Pro 16 II) in an XT compatible 8086 computer, I encountered the problem that the drivers and tools (like the mixer initialization tool ...

I am sorry, if this is not a good place to ask, but is there any general rule of thumb about how much precious metals could you expect to get out from 197x(?) printed circuit boards, especially Soviet ...

For those of you who are unfamiliar, Super Mario 64 is an extremely competitive speed game, and because glitches are allowed on most major leaderboards, many very talented glitch hunters have torn the ...

I just got a Z84C0020PEC and wired it up to test it, using this circuit: Except that I've added LEDs to A0 through A9. It appears that A0 through A6 operate correctly, but A7 though A9 (I've not ...

I've heard the term 'DMA' being used a lot in reference to older consoles. My very basic understanding is that it's a way for the console to access memory directly. But directly as apposed to what? ...

I am a big fan of the TV show lost, and I was trying to make the Dharma Initiative logo. But at certain point I couldn't add new lines of code and the final part of the logo was cut off. I tried to ...

Does SUB B on Intel 8080 set the auxiliary carry flag when the accumulator and the B register are 1 and 0, respectively? On Z80, which was designed to be a backward-compatible, albeit not fully, ...

According to the cc65 documentation, a string constant in assembler programs can be defined with the .ASCIIZ command. However, I could not manage to sneak control commands in, for example, the ...

The Censor 932 CPU architecture has one instruction type that takes a 3-bit "index register" field, but looking at the rest of the instruction set, I can't see any instructions that read, write, or ...

I've been looking into implementing Gameboy Link Cable compatibility into Bizhawk (which does not support it yet) using Lua. The problem is that I can't find any mention of how it works online. I ...

I stumbled upon a divergence in the ASCII upper case/lower case handling when using assembler and linker of the cc65 suite separately (I used cc65 V2.15 on Win10). For a test I made the following ...

I like to play with old networks, uucp is really and advanced(is from the 1978) for that time. I have setup a uucp server in a tru64 unix server. On tru64 server I have edit /etc/inetd.conf uucp ...

I'm curious if anyone is aware of actual uses of Unix on the Heathkit H11? I don't see any technical reason a memory-expanded H11 couldn't run Unix, but can't find any examples of it doing so.

The 6502 has a group of opcodes which copy bit 5 from the opcode into one of the status flags. (I know it's not implemented this way, but it looks as though the bit fields are: 2 bits to select the ...

I'm trying to remember an old game I used to play as a kid. It may have been a commodore 64 game, not sure. All I remember was you answered questions like for math or something like that and as you ...

I´m planning to build a small computer system, based on the W65C02 from Western Design Center. This computer system should also have a VGA interface with a graphic and a text mode, defined with the ...

It's something I've always been wondering: Almost all of the hardware registers on the Gameboy are placed between $ff00 and $ff7f (with plenty of gaps and empty space), the HRAM is located between $...

The stats are: https://en.wikipedia.org/wiki/Cray-1 Memory‎: ‎8.39 Megabytes (up to 1 048 576 words) CPU‎: ‎64-bit processor @ 80 MHz The 24-bit address arithmetic was performed in an add unit and a ...

This article is about Ken Thompson's old Unix password hash being cracked. One line in the article intrigues: "Even an exhaustive search over all lower-case letters and digits took several days (...

On all Unix-like operating systems, sudo is often provided as the standard package for executing commands as superuser (or an alternative user). When sudo is invoked by the user for the first time, ...

I have a DEC VT220 from 1986, it has a composite output. Works great in all its max-19200Kbps monochrome glory. The composite output plug is a BNC, and it looks like BNC-to-RCA composite jack ...

In spring of 1978, Apple took the updated 6502 BASIC from Microsoft, fixed some bugs and added some new commands, and released it as Applesoft II. This was soon released as a ROM set (shipped standard ...

It had long been my impression that while brackets [ and ] could be displayed by the Apple II, the standard Apple II keyboard was not capable of generating them. Some time ago I noticed that on this ...

The Neo Geo had a remarkable capacity to scale sprites, as we can see in fighting games, but it does not have any racing, flight or any game that simulated a non ray casting pseudo 3D to my knowledge. ...

I own a fairly early Amiga 500 with Kickstart 1.2 ROMs, Commodore Logo key and the OCS Agnus 8371. Is this system completely compatible with Workbench 1.3? Or does WB 1.3 require Kickstart 1.3 ROMs? ...

My SE was working fine until I took it apart to clean it, and after reassembly the tube won't turn on, what could cause this? enter link description here

I just spent an enjoyable day at the local ham fest with my father - digging through boxes of other peoples junk. I'm a sucker for weird electronics, especially when it's in the free pile, and so I ...

Why do some IBM PS/2's have a red switch, while others have a white switch? Does the red or white power switch on the power supply signify something about the model number, CPU, or options that the ...

Inspired by a YouTube video I saw recently that claims a very high uptime for the computers on the Voyager probes, I was curious -- what computer currently has the longest continuous runtime? For the ...

I kept one floppy from my Commodore 128 (which I used mostly in C64 mode), which is written Oxford C compiler. It is a 5.25" floppy. Don't ask me why I kept just this one; probably because I thought I ...

I want to compile and run a Hello World program in C with the cc65 compiler for an unexpanded VIC-20 model. For printing I'm using the conio.h function cprintf, since the conio implementation requires ...

I'm looking for the exact tape data format of old SVI-318/328 computers, some kind of whitepapers explaining it. I've obtained several information from a real tape, but I don't known if the infered ...

If you look at the results of the Rugg/Feldman benchmarks, shown in this Wiki entry, you'll see that Sinclair ZX80 is much faster than Sinclair Spectrum on all tests despite the fact that both ...

I only recently learned of the JOSS language, and then only through a roundabout fashion from an interview with David Ahl where he mentions FOCAL. This led me to read the available manuals for all ...

Back in the 90's I remember playing a 2d shooter-platformer game on my family's home computer. I sucked at the game, and as far as I remember I never managed to beat the first level. The details I ...

I remember playing a side-scroller at a Babbage's at the mall (on probably a sweet Compaq; I don't think it was on a C64, an Amiga, an Apple, or anything more exotic), probably around 1993, where the ...

From the website https://plan28.org/ and blog http://blog.plan28.org/, it seems that the original documents are scattered and hard to decipher. It might be that the plans are not even close to be ...