All Questions

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 //e desktop computers. So I have a question that has haunted me: The disks were floppy disks, often the Verbatim brand, to ...

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, ...

I'm interested in doing some practice work around legacy systems out of pure recreation. I want to extract data or information related to a DOS game running on the 16bit arch of Windows 3.1 (1991 ...

I recently picked up an Atari 800xl from ebay that seems really solid and I am using a DIN to RCA cable through an AV to HDMI adapter to connect it to my flat screen tv. This all seems to work except ...

I just came across this amazing 1976 article by Woz. In it he describes a relatively complete floating-point system for the 6502 with a 32-bit format (similar to earlier MS code). I understand the ...

Note: I only have the MC68040 USER'S MANUAL at hand. In chapter 8.2.1 "Access Fault Exceptions", it is stated that those exceptions can be caused by Bus Error or Internal Access Faults and by that ...

How can I connect a Legacy scanner with a Centronics 50 output to a laptop with USB ?

I am working on an FPGA implementation of the original Space Invaders arcade machine and I'd like to implement access arbitration between the CPU and the video system. I can imagine several ways of ...

Is there a way to connect the 1983 Microsoft "Green-eyed" mouse to a modern PC or preferably Mac (running Windows on virtual machine)?

A Sony Clié (PEG-NX70V) has come into my possession. It runs Palm OS 5.0, and has both a MemoryStick slot and a CompactFlash slot. The latter is only designed for use with a WiFi card, as Sony ...

I have an Atari, which is working correctly, but the power supply makes this hissing noise as soon as it is turned on. What may cause it?

I found this drive in one of Atari lots. Apart from few mentions in old articles I can't find any info whatsoever. Can you help please?

I have recently built a 80386 system. Lacking any AT PSU I connected a PicoPSU using an ATX->AT power adapter. Only card connected was a gpu (Trident TVGA 9000i). System performed BIOS checkup ...

I was browsing old FAQs on the wayback machine(1) and noticed that it said some early Mitsubishi Diamond Scan monitors, and reportedly the Dell Ultrascan 17ES monitor(2), use a standard HD DE-15 VGA ...

I was looking into the Apple II disk server (See below for background information) and curious if there is a tool that can actually convert .DSK image to .MP3 file, as the underlying c2t only supports ...

I started using IRIX 6.2 so I could do some Nintendo 64 Development for the IRIX community. WARNING: IT IS A VERY WEIRD SITUATION! Also, I am using root. The file manager GUI states that the files ...

PDP-11 BOARDS The following boards are all Digital, except where stated. There is one board except where stated. All boards came off working systems but I can’t guarantee they are still working! I ...

I just saw this video of a mechanical calculator dividing by zero. Did any mechanical calculators or computers ever provide for a failure mode on divide by zero? Or did they always handle it by ...

I'm working on Atari STe, which has dodgy caps on PSU board. 2 of them are in desperate need for replacement. Can anyone suggest quality brand to extend the life as much as possible?

Infocom's Z-Machine, designed in 1979, compresses text using a basic 5 bit code which is not very efficient in practice, achieving maybe a 1.5:1 compression ratio. Huffman coding would be far more ...

When DOS released in 1981, the assembler that came with it produced .OBJ files that were OMF format. However there was a predecessor to it, M80.COM that ran under CP/M and also used .OBJ as the file ...

If you pressed one of the joystick buttons on the TRS-80 Color Computer while running BASIC, it would act as if @ABCDEFG were typed. Pressing the other joystick button would similarly type out ...

I have what appears to be an early games console (supported games are variations on the theme of "pong", or ball and paddle games) manufactured in South Africa. Does anyone have more information or ...

Apple II computers other than the IIgs (which uses ADB) have a hardwired keyboard combined with the paddle/joystick ports for input. What combinations of modifier keys can you detect? I know that the ...

I'm facing a Parity Error problem on my new 486er DOS Retro PC. Every now and then a running software crashes with a Parity Error output on screen. This happens for different software so I think the ...

In the Soviet Union, Z80 compatibles were manufactured under at least the following designations: Т34ВМ1 КМ1858ВМ1 КР1858ВМ3 At least some of these were manufactured from the U880 masks that were ...

What was the first third-party commercial application for MS-DOS intended for IBM PC-compatible computers?

What is the oldest commercial MS-DOS program that can run on modern versions of Windows (such as Windows 8.1 or Windows 10) without third-party emulators?

I see many references to a paper by Andrew Tanenbaum that demonstrated the vast majority of constants would fit into 13-bits, and I seem to recall it being in my university text on CPU design. However,...

I remember CAD being a major driver for PCs with high-end graphics cards; specifically AutoCAD was rising quickly in popularity around 1990 as PCs were able to compete with very costly CAD ...

I can't get the music audio working for the 1994 version of Raptor. Does anyone know how I can remedy this? I'm not sure if this is the correct forum for this question, but here goes. I have an ...

Old processors came out with support chips. That is, there was a family - the processor and its chips. Over time, the same kits came out with higher frequencies. Will the circuit work properly if ...

I recently purchased an Apple //e online as well as a BMOW Floppy Emu in order to emulate some disk images. After working with it successfully for awhile, this monitor consistently appeared in lieu of ...

I have Amitek Hawk for my A1200, the board came with wrong RAM and apps were crashing with 8003 Guru error. After contacting the seller I was told by mistake wrong SIMM was shipped and I received a ...

The Apple IIgs (last, ROM03 version) came with 128K of standard RAM and 1M of FAST RAM. The distinguishing characteristic of the FAST RAM is that code running from there can run at 2.8 MHz instead of ...

Early DRAMs have a multiplexed address bus. Briefly speaking, to access a word, one needs to... Put the row address on the bus, and latch it using the falling edge of /RAS signal. Put the column ...

I make a homebrew (for hobby) game console on Z80A, and I need help. Now I'm stuck - I need to be able to count milliseconds and microseconds in the code. For example, how it is done in Arduino : ...

I got an Amiga 2000, board Rev. 6 Does anyone know what is is? (click to enlarge)

Preface: This question does in part intersect with Use of undocumented opcodes, but targets especially the 8086 instruction handling. I was reading Tanenbaum's "Operating Systems, Design and ...

I'm having an odd issue with the aforementioned system, the A/V receiver is a RCA STAV-4180 unit, and being from 1996, it's still a great unit. So far, while it's tape output for recording does have ...

I'm trying to create a boot disk for the Kaypro II (from scratch). I've been using cpmtools to generate file system images for other platforms, mostly with success. However, the Kaypro II has this ...

I'm doing some mode x programming and I noticed that my vram to vram copies are much slower than I expected. My copying method was described by Michael Abrash in his Graphics Programming Black Book ...

(Following up from Monitor for an SGI Octane?) I booted both my Octane and Octane 2 machines for the first time. I have a monitor connected via a 13W3-to-VGA adapter, but no PS2 keyboard or mouse yet....

I got an Amiga 1200 off ebay and it works great, board looks perfect, no leakage, no bad traces, nothing, and yet I have this mysterious mod I've never seen before. Does anyone know what it is?

In the eighties, there was a vast flowering of small independent software companies. Business and productivity software for the IBM PC, all manner of novelties for the Macintosh, games for the ...