Questions tagged [hardware]
Retro hardware generally: boards, extension cards, power supplies, peripherals. Use more specific tags as appropriate; use [case] instead for enclosures.
532
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Did playing sounds on the PC speaker keep the CPU busy?
The IBM PC and early successors came with an internal speaker that could play simple sounds. According to https://en.wikipedia.org/wiki/PC_speaker
However, because the method used to reproduce PCM ...
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3
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How was the 80186 incompatible with the IBM PC?
According to https://en.wikipedia.org/wiki/Intel_80186
The 80186 would have been a natural successor to the 8086 in personal computers. However, because its integrated hardware was incompatible with ...
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1
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Was sector size under software control on the original IBM PC floppy drive controller?
The original IBM PC used a 5.25" floppy disk format of two sides, 40 tracks, 9 sectors per track, 512 bytes per sector, for 360K per disk.
As I understand it, a significant amount of disk space ...
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3
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What was the second most common incompatibility in MS-DOS machines? [closed]
When the IBM PC was released, it did not take long for people to figure out that there would be a big market for compatible machines.
The first wave relied on MS-DOS as the compatibility layer. The ...
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Pulling my hair out over a 4-bit architecture, there ought to be some law here somewhere, is there? [closed]
I am trying to build the most simple CPU possible. And doing it on bread boards. There is a popular movement, one of the biggest protagonists of that being a certain Ben Eater, who is a good teacher, ...
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3
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'What' used spare memory on the TMS9918?
'What' used spare memory on the TMS9918 Video Display Controller?
By 'what', was it
Something pre-installed on the computer like Bios or Basic or something, I assume the main cpu s themselves were ...
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2
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Why does the Galaksija's latch include some kind of address remapping?
The Galaksija has a 6 bit latch used for various bits and bobs, notably the part of the scanline counter which contributes to character generation, but also, it has a bit for clamping A7 high, and ...
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Is the thirty something year old RJ45 jack as small as it will ever get? [closed]
Why are micro-ethernet adapters not a thing? A physical adapter that takes our thirty year old standard sized RJ45 jack on one side and and plugs into a TabletPC on the other.
Every other form of ...
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4
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2
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Aside from legacy systems, are there any contemporary uses for magnetic core memory?
Core has some interesting properties (nonvolatility, high reliability, resilient to radiation) that might make it useful in some situations. I know early versions of the computers on the Space ...
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0
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Need help checking an ADC0808 / ADC0809 chip in a arcade shooting game
Main Question: How can I check a ADC0808 chip to determine if it needs to be replaced or if my issue is something else? Any advice you can offer is SO appreciated!
ADDITIONAL INFO
When the arcade is ...
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4
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Is this a computer screen in 1956, and if so, what is it displaying?
The photo below shows what may be a CRT for the TX-0 (transistorized experimental computer) in 1956, referring to what may be a CRT on the left side, not to the CRT on the right side .
If that is a ...
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2
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Why does the 80486 take longer to execute simple instructions than complex ones?
The 80486 processor can execute many instructions in a single cycle, such as a register-to-register add instruction (ADD EAX, EBX, for example), which one would generally assume is fairly complex, ...
- 2,212
1
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2
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What is the brand and model of this AT chassis case from the early 90s?
A friend is trying find the original brand and model of this old 1990’s generic case. An ad from computershopper would help.
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8
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Why were optical drives not used as secondary storage instead of magnetic drives?
What prevented optical drives from being used as the dominant secondary storage like the magnetic disk drives, in PCs? Was it entirely technical limitation or other issues like late development and ...
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1
answer
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Who built the first electric/electronic adder?
The first electricity-based adder presumably used relays. (The electromechanical relay was invented for the electrochemical telegraph for repeaters in 1831 by Joseph Henry (1797-1878). I can't figure ...
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Was it possible programmatically to manipulate the volume as well as the pitch on computers with no sound chip?
On early versions of many 8-bit computers like the Apple II, Spectrum, and even the IBM PC, there was no sound hardware other than the simple "beeper".
Programmers made sound by hitting a hardware ...
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2
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Why did computers settle for instructions with multiple machine cycles instead of investing into larger ring counters? [closed]
On the 8080 and 8085 microprocessors, a LDA instruction took 13 timing(or T) states to execute. This could be solved by using a ring counter that could generate said 13 T states,as well as having ...
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1
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Did the Samsung SPC-650 have any hardware or firmware differences to the genuine Sinclair Spectrum+?
There was a clone of the Sinclair Spectrum+ in South Korea called the Samsung SPC-650 that looks identical to original British version with just an extra model number/logo. It even retains the ...
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1
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Did the Timex Sinclair 2068 and the Sinclair ZX Interface 2 use totally different hardware and software techniques?
Sinclair released an add-on for the Spectrum called the ZX Interface 2 that provided joystick ports and a cartridge slot. It wasn't successful and only a few cartridges were ever produced.
In the US, ...
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2
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Reusing original Palm memory cards
I have a number of non-functional older PalmOS devices (of the 68000 processor variety, not the later ARM processor models). I'd like to be able to reuse the memory cards from these in new ...
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2
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How do you use the INHIBIT pin on the Apple II bus?
Pin 32 of the Apple II bus is a signal called /INH (short for "INHIBIT"). Some of what I found online about using this pin for an Apple II expansion card suggests it was inconsistently implemented ...
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1
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How Amiga A590 autoboot ROM and bootable floppy disk works?
Commodore A590 was a peripheral hard drive and memory expansion unit for Amiga 500/500+ computers. It provides SCSI and XT-harddrive controller and 2MB Fast Ram. Here is the Big Book of Amiga Hardware ...
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1
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Which computers used the Intel 82786 graphics chips, and what sort of commercial success did that chip attain?
In the late 1980's, Intel offered the 82786 graphics chip, with specific support for windowed environments. I remember it being covered in Byte magazine, but don't remember seeing any applications of ...
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2
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Why would installing Windows 9x on a Sager NP8200 or Wedge 466/DX2 laptop brick the system?
In the setup.txt file on the Windows 95 and 98 CDs (located in the \WIN95 [Windows 95] / \win98 [Windows 98] folder), which contains important information on setting up Windows and solving or working ...
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1
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How can I fix this clacking sound made by the Game Boy speaker?
I have a Game Boy, and whenever it tries to play sound, the sound is very quiet but there's a loud clacking sound.
Here is a sample. In this case, it is Tetris Attack playing:
https://soundcloud.com/...
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4
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1
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Hardware implementation of the isometric tile engine. Is it possible, did it exist?
We are talking about a hardware (and not software over hardware, as for example in some games on the SNES console) tile engine with multi-overlapping rectangular (rather than square, when the image ...
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Purpose of turbo switch on systems unable to slow to 4.77 MHz?
I have a PC with an Intel P133 (133 MHz). The motherboard (PcPartner MB520NH) only allows for it to be slowed down to 75 MHz at the least via jumper settings, but no lower. Yet the PC's case has ...
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How did I fry my SID chip?
I recently got a SID chip (8580r5) for $35 and got it playing music. I was really happy about it. I hooked up a small amp chip to the 9V supply momentarily (it didn't work, I was building that part of ...
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10
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What 8-bit microcomputer systems multiplexed multiple physical ports on a single controller?
The NEC PC-8201 had three serial interface ports on the back,
"RS-232," "SIO1" and "SIO2." These were all driven by a single IM6402
USART, switched between each physical port via bits 7 and 6 of IO ...
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Performing 16-bit port I/O on the RTC
Why can’t the RTC (0x70, 0x71) read and write 16 bits at a time? For example:
mov ax, 0xa8f
out 0x70, ax
I have found in a 286 BIOS that did this (BIOS ID string: S286-6181-...
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Why did the CDC 6600 expand the word size to 60 bits?
According to http://www.quadibloc.com/comp/cp0201.htm
The CDC 1604 used 48-bit floating point with 11 bits exponent and 36 bits mantissa. There was also a double precision format (which I believe was ...
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6
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1
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How many hours of labor did it take to assemble a minicomputer?
A minicomputer like the PDP-8 contained several thousand discrete transistors and other components, all of which had to be soldered by hand, and that was among the simplest computers on the market; ...
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DEC Alpha: why no 8/16-bit load/stores?
The first version of the DEC Alpha had no load/store instructions for 8 or 16-bit values; if you wanted to deal with data of such sizes, you had to do it by shifting and masking values in registers as ...
- 55.7k
3
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3
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When first CMOS versions of Z80 became available and were they ever used in (non-portable) home computers?
When Z80 first became available on the market in 1976 it was made using NMOS technology. It is the version that is likely to be most familiar to people interested in retro-computers. For example, to ...
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2
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What's the Motorola microprocessor with two sets of registers to avoid costly context switch?
I remember reading somewhere (maybe on Hacker News or Lobsters) that Motorola made a microprocessor some decades ago with two sets of registers. This means when handling an interrupt, it does not need ...
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Why did extracodes fall out of favour?
Once you have an operating system that provides services callable from programs, you need to provide a way for programs to request those services.
These days the general approach only requires a ...
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1
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How to set up a payphone phone network central office
I would like to setup a network of payphones inside my college as part of a retro phone systems / artistic interactive exhibit. I would like to be able to use the payphones to make calls inside the ...
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What was the cost of the PS2 chip in the last PS3 to have it?
The PlayStation 2 provided backward compatibility with the PS1 by essentially incorporating an entire PS1 on a separate chip. It kept this arrangement permanently.
The PS3 started off providing ...
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In the 1970s, had there been a way that a home computer using a TV as monitor could get FCC approval for Apple II style slots without cheating?
I’m reading the book “Atari Inc.: Business is Fun” by Curt Vendel and Marty Goldberg. (By the way, it’s a fun read, highly recommended.) It states that when the Atari engineers had been developing the ...
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How did most fifth-generation consoles avoid wobbly graphics?
According to Why do 3D models on the PlayStation 1 “wobble” so much? the PlayStation had a problem with wobbly graphics because
Filling a triangle involves visiting every pixel within it and deciding ...
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How much memory did the PlayStation development kit have?
The PlayStation 1 had two megabytes of main memory, one megabyte of video memory and half a megabyte of audio memory. Squeezing everything to fit into these limits was one of the big challenges of ...
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6502 reset pin: always needed on power on?
The 6502 pinout has a reset pin, which presumably would be used if a reset button is pressed on the machine containing the CPU.
But the 6507 contains the same pin. The 6507 was designed at the ...
- 55.7k
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6
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Did any RISC CPU ever take more than one clock cycle per instruction?
Classic RISC CPUs like ARM and MIPS basically offer the trade-off: simple instruction set, but instructions execute in one cycle for good overall performance. (It gets more complicated in later times, ...
- 55.7k
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6
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Why did early arcade games use vertical displays?
Surprisingly many early arcade games, such as Pac-Man, Galaxian and Galaga, mounted their displays vertically, in portrait rather than landscape orientation. (From the perspective of the electronics, ...
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1
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How did the Donkey Kong arcade hardware provide 128 sprites?
According to https://en.wikipedia.org/wiki/Donkey_Kong_(video_game)
The Donkey Kong hardware has the memory capacity for displaying 128 foreground sprites at 16x16 pixels each and 256 background ...
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3
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1
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ABEL HDL: What was the purpose of the 'flag' keyword?
Some context first: ABEL (Advanced Boolean Equation Language) is an old hardware description language which has been mainly used in the 80/90s to program CPLDs. Unfortunately I have not found any ...
user6734
25
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3
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Why was it not possible to cost-reduce the Amiga 500?
According to 'Commodore: The Final Years' (whole trilogy highly recommended, BTW), page 129, 'Jeff Porter realized it would not be possible to significantly cost reduce the Amiga 500 to get it into ...
- 55.7k
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Cost of unrestricted sprites
All the game consoles of the second through fourth generations, and several early home computers, had sprites, which were valuable though costly, e.g. the VIC-II spent 2/3 to 3/4 of its area on ...
- 55.7k
9
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2
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442
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Were expansion slots fundamentally incompatible with FCC regulations?
The Apple II provided the ability to connect to your TV (as opposed to purchasing a dedicated monitor). However, at that time, the FCC criterion for applying stringent RF emission limits was 'device ...
- 55.7k
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1
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Fan for old socket A Athlon cooler [closed]
I put together a retro gaming setup with a 2000ish spec (can post specs if required) and it's come together pretty nicely except the CPU fan is insanely shrill (it's a Coolermaster something).
If I ...
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