All Questions

Based on my understanding, the bitness of a CPU specifies how much memory it can address (which is determined by the size of the CPU's address bus I guess). For example: a 32-bit CPU can address 232 ...

The address bus of the Intel 8086 CPU is 20-bits, and when you want to specify a memory address to read from or write to, you would form the memory address using a segment register and an offset ...

I'd like to build an FPGA replica of a home computer based on the Intel 8080. I am not looking to design my own computer, since I would like to tap into an existing software base. Were there any ...

The Intel 8086 CPU uses memory segmentation, which means that when, for example, you write the value 123 to the memory address 1001, the memory address 1001 will actually get converted first into ...

From the Wikipedia's 65CE02 page: Internally, the pipeline of the 65CE02 was redesigned to reduce the number of cycles required to execute an instruction. The 65CE02 can recover faster from ...

I am looking for a dimensioned drawing of a 64-pin SIMM PCB like the ones used in the Macintosh II series for the ROM SIMM. I looked in Guide to the Macintosh Family Hardware and Designing Cards and ...

Many people remember this operating system as not exactly a walk in the park, namely that it could crash as early as during the installation phase or at unexpected times when the user wasn't doing ...

It seems to me that there's effectively two ways that the zero bit could work. Z is set iff the result of a computation is mathematically equal to 0. Z is set iff a bit pattern consisting entirely of ...

The order wasn't easy for me to memorize. I would like to know if there is a historical story.

The original gameboy, GBP and GBC all had screen resolutions of 160x144[1] while the Game Boy Advanced had a resolution of 240x160[2] So how does the actual stretching occur? It seems pretty uniform, ...

I am trying to make a portable version of a Sega Genesis Classic. (See this example on Youtube.) I'm wondering what kind of display module I would need to solder to the board for this project.

Further to my previous question, I am wondering how best to connect an SCM Swapbox "SBI-D2P" (Classic X2) PCMCIA card reader to a modern PC (PCI/PCI Express/SATA/USB). I am aware there are USB PCMCIA ...

I just recently stumbled across information about DDR minicomputer P8000 and its unixoid operating system WEGA. The website above as well as Wikipedia seem to claim some compatibility or even ...

My father's computer in the early 90s (probably 1991, or at the latest 1992) had a piece of software that acted as an application launcher. I think it was simply called "menu". Its graphics were ...

I'm trying to understand how video memory worked on the Commodore64 in text mode. I see that the VIC-II has a memory setup register (at $D018) that keeps track of some of this information along with ...

I have connected two old Conner Peripheral IDE HDDs to a modern computer using Deltaco USB to SATA/IDE adaptors. The drives in question are: Conner CP30121 (120 MB) Conner CFA2161A (210 MB) Both ...

I have a cople of HP BASIC (HP9000) files that have been saved in a non-ASCII format (HFSLIF?). Does anyone know of a conversion utility to get the code readable? The files are already on a win7 ...

I frequently see these kinds of pins go for sale, Both of the two pins in the picture read "Bell Telephone Laboratories 1875". One of the pins has two stars, the other three. What did it mean to ...

The IBM PC was cloned very early on, and many third parties made hardware peripherals. This required users to run an OS, install drivers, manage IRQs and hardware bus addresses, etc. Why was this a ...

One and half decade ago I had an black IBM Thinkcentre tower. The specs were: Pentium 4 2.66 GHz 256 Mb IBM RAM (which later got upgraded into 512 Mb RAM), 40GB HDD, XP Pro SP3, GeForce 2 MX 400. ...

While for other platforms of that era (primarily, Amiga), putting a game on a bootable disk was quite a normal practice, this approach never taken off on IBM PC. Why not? I do remember people having ...

For the ZX Spectrum there is a project called ZX Pie. As the name suggests, it's a board attached to the ZX Spectrum's expansion slot that 'listens' the Address Bus and the Data Bus and connect them ...

I want to use my old PS/2 mouse & keyboard with my Dell Latitude, which has no PS/2 ports. I am fully aware that the easiest way to do this would to use an active PS/2 to USB converter, like this ...

Acorn's BBC Micro series is well known for the range of add-on processors (or Second Processors) that could be connected through it's Tube interface. These included the 6502, Z80, 80186, and also the ...

What was the decision making process that lead to the IEC to create "kibibytes", "mebibytes" and so forth? To me it seems like kilobytes were well established as 1024 bytes, both by programmers using ...

I am wondering if anyone has a pointer to a good source of "classic" BASIC programs, in text format. One would think this would be easy to find, but unfortunately VB so pollutes the results as to ...

PC displays almost always targeted 4:3 CRT displays. And indeed, VGA and most super-VGA modes had 4:3 aspect ratio resulting in square pixels - except the odd 5:4 1280*1024 mode. This mode even caused ...

I am having some difficulty getting a board that has a Dallas Real Time Clock DS12C887+ to behave. Not sure if the problem is the RTC or not but am in the investigative stage and got the cross hairs ...

I've never used NetWare 5.x 6.x but if I remember correctly versions 3 and 4 required you to boot to DOS partition and then load NetWare server files from it. I could never understand the logic behind ...

What was the first computer to have interactive text on a CRT ? That the text on screen responded to key-presses without significant delay . I remember seeing some very early radar-installation CRT'...

In 1994 or so, we had an old computer at my primary school. I remember finding out that it had a park command. From reading its documentation, it said that this command should be executed prior to ...

During the latest gaming press release, Square Enix released remastered versions of all of the classic Final Fantasy games excluding Final Fantasy VIII. The alleged reason is due to the lost source ...

I was playing Hypnospace Outlaw, a game about a retro-themed OS. This OS has a peculiar behavior that when loading a webpage, wiggling the mouse cursor will load the page faster. That reminded me of ...

I have recently gotten my hands on a "Movemaster EX RV-M1" 5-axis robotic arm (image) manufactured by Mitsubishi in the 70's (I think). Sadly, I only have the arm and one set of cables I don't want to ...

I can find information about how characters were used to structure transmissions in general, and I can find information about transmission characters which are still commonly used today, though ...

Config: WinUAE 4.2.1, CPU 68020, 24bit, FPU 68882, 8MB FastRam Z2, A1200, CF 4GB Transcend, BetterWB 43, Dopus 4, When I try to copy folders from PC to CF Partition (2.4GB, pfs3) it goes alright, ...

Generic beige-box PC clones like the ones pictured here often had an indent for the manufacturer's badge to be stuck on. Were these all a standard size, and if so, what were the dimensions?

I did enjoy the software that schools provided with the Apple //e in the late 1980's. My memory of word processing software was: Zardax Multiscribe I was in the Australian school system. So other ...

Does anyone know an old game, probably from 1980s or early 1990s where the player goes through a top down labyrinth opening secret rooms, collecting treasure, and food, and keys, trying to get to a ...

I'm trying to set up my system using UAE 4.2.1 64 bit and an excellent step by step guide provided by phraxoid: https://devtty.io/2018/07/computing/how-to-setup-commodore-amiga-workbench-os/ The ...

I occasionally need to work with console commands and 100% of the time I want to redirect my output to a file I fail to redirect stderr as well as stdout the first time. I can't think of a single ...

The Wikipedia article on the 65C02 is missing an introduction date for any of the mentioned models. I did a bit of poking about with no success. Does anyone know when they were introduced?

Here's some screenshots from the youtube clip [1986?]: Magnum P.I (Thomas crashes Higgin's security computer system): Then Higgins says OMG Magnum you've crashed the "dracos three". I think he said ...

In the early 1980's there was a small handheld device that looked like a calculator. It was a tool to teach beginner level programming in BASIC. Its ad slogan was "keep it near you". I never had one ...

When I began high school in 1987 all the computers in the lab were Apple IIe desktop computers. A question has haunted me since then: if you inserted a floppy disk "upside down" the Apple IIe would ...

Inspired by this question on ASCII, I have wondered similar things about EBCDIC. At work we have an EBCDIC file that gets sent to a mainframe (I presume an IBM one) and to view it on my laptop I ...

I only recently learned that the early MS BASICs had integer variables and do not have a machine that runs it. So perhaps someone with a PET or C64 could answer these questions? For one, were there ...

Satoru Iwata's story of saving the development of Pokemon Gold & Silver by compressing its assets to fit on the GameBoy Color cartridge is something of a legend. Iwata optimised the game so much ...

Anyone who has dealt with strings at a low level (e.g., writing a parser in C), knows that doing so tends to involve frequent checks of—either manually, or through isalpha(), isalnum(), etc—whether a ...

Have there actually been any commercial operating systems with a single-level, limited capacity file directory? I remember vaguely that the early versions of MS-DOS FAT12 may have had a single layer, ...