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TL;DR: it took a long time (on PCs) because the industry wasn’t ready to push it. Scroll down to “Why did it take so long?” for details. Shutdown screens That screen comes from Windows 95 and its successors, 98 and Me. Windows NT showed a plain dialog box with a “Restart” button. Other operating systems which cared about managing the shutdown process had ...


77

The one-word answer to your question is "badly". The way to create random numbers quickly is via a Pseudorandom number generator (PRNG). That Wikipedia page gives the history of PRNGs and in particular notes that linear congruential generators are/were common, with quite a few failings including periodicity (i.e. it cycles through the same sequence of ...


70

Anyone who considers arithmetical methods of producing random digits is, of course, in a state of sin — John von Neumann The method that RAND used to calculate their A Million Random Digits with 100,000 Normal Deviates is described in this brief paper: History of RAND's Random Digits: Summary from 1949. In summary, the gated output of a gas-filled ...


69

The Turbo button originally adjusted the clock speed of the computer between the full speed of the machine and a slower speed intended to be compatible with something more industry standard. It wasn't at all uncommon for software to be written with a specific speed of hardware in mind and either fail to operate completely or operate in a way that was ...


68

In the 1980's a certain bank with its headquarters in Edinburgh has a problem with (IBM) disc storage that had to be kept online for live customer account information for branch and ATM machine operation that it ran out of city buildings to put the disc drives in. Yes: Not just a building, but buildings. Luckily, just after that time radical developments ...


66

The architecture of most "color computers" of the 70s-80s was very tightly built around the NTSC color video standard. Almost all of them had a 14.31818 MHz crystal. Note that this is four times the 3.579545 MHz frequency of the NTSC color standard, which was called a "color clock". They divided that crystal frequency to derive their actual clock ...


65

Caveat: It might be useful to distinguish between high volume low cost computers (like the mentioned CoCo) and low volume high cost machines (like Intel boards - or workstations). I assume the question to be rather about these high volume low cost machines. Why were chips socketed in early computers? There are several reasons: Most important: Chips ...


61

One basic distinction in acoustics is the one between sounds that oscillate with a pattern that is repeated over time and sounds that are chaotic in nature, and show no repetitive pattern. Sounds of the first type may be referred to as "tones". There are a few tones that can be described by a very simple mathematical equation, for example the the square ...


61

Having the display vertical reduces the width of the cabinet. This means that a game machine can be fitted into a smaller space in a pub/bar, or in an amusement arcade where machines are in rows you can get more machines (potentially a third more) into the same space. One-third more machines means one-third more revenue. The orientation may also have been ...


60

The socket (or rather inlet) is most definitely standard, it’s a IEC 60320 C14 inlet. The standard was published in 1970. C6 and C8 are commonly used for laptop power supplies and smaller audio equipment. There are a number of reasons to use this arrangement on computer power supplies, monitors, audio equipment etc., including: using a standard inlet with ...


60

Why did trackballs disappear? To start with, they didn't. They are still around and can be bought in many variations. For example, Kensington sells six kinds of trackball, and Logitech sells three. Only their time attempting to work as a general pointing device is gone. Nub. Low-tech, cheap, compact and reliable, but miserably imprecise. Did they ever ...


56

It definitely does not hurt to open the case and have a look at the PCB. When opening, be especially careful with the keyboard ribbon cables - They are apparently known to become very brittle with age and tend to easily break. The main victims of age and heat are electrolytic capacitors which are known to leak or bulge and leak over time, losing their ...


54

Simply yes. And not just a few instructions, but whole CPUs have been developed with languages in mind. Most prominent maybe Intel's 8086. Already the basic CPU was designed to support the way high level languages handle memory management, especially stack allocation and usage. With BP a separate register for stack frames and addressing was added in ...


53

A nice one - and coming up every now or then. TL;DR The Apple IIs video logic produces a B&W bitstream at the right frequency to bedazzle an NTSC TV set in a way to make it 'see' colour. The colours produced are based on the way the bitstream creates interferences that are detected by the TV set as colour information. The encoding is rather a series ...


51

Video game hardware, whether for home consoles or arcade machines, is designed pretty much from scratch. Hardware designers have pretty much free rein on choosing what CPU to use, basing their choice on factors like cost and ease of programming. The Intel 8086, quite frankly, was a poorly designed processor and was never well regarded. While you could ...


47

A UART (Universal Asynchronous Receiver-Transmitter) is a particular kind of hardware device that uses digital sampling to convert serial data that uses embedded start and stop bits for synchronization into and from parallel data. Not all forms serial communication use start and stop bits, and not all devices that use this form of serial communication uses ...


47

Interesting question with an interesting answer. First let me get one thing out of the way: One example from this answer mentions how C pointers were, at least in part, influenced by the design of the PDP-11 It's a myth to suggest C's design is based on the PDP-11. People often quote, for example, the increment and decrement operators because they have ...


45

After some more research, I believe I've stumbled across the real answer: The VIC-II and SID used a larger process node size because Commodore's fabrication line circa 1981 was uniquely positioned produce chips at that size at effectively no production cost whatsoever. Based on what I've read, here's my best guess at what Commodore's fabrication situation ...


45

When did computers stop checking memory on boot? Never. I remember my old 8088 used to do this (640K OK) but can't remember seeing anything like this since. Does this still happen and it's just not visible? Exactly. And it has been simplified and speed up as well. But more important, it's usually hidden under some manufacturer boot logo or whatsoever ...


45

TL;DR Because it needs the least chip count and thus makes it the cheapest. It's a Sinclair. Full Story: The Sinclair ZX80 used a Z80A running at 3.25 MHz. But this chip was rated for 4 MHz. Why was it run below rated speed? And the chip would have run for sure at more than 4 MHz. A computer design isn't about what a chip is rated, but what it's for. ...


44

One interesting example of programming languages driving hardware development is the LISP machine. Since "normal" computers of the time period couldn't execute lisp code efficiently, and there was a high demand for the language in academia and research, dedicated hardware was built with the sole purpose of executing lisp code. Although lisp machines were ...


43

Was it really that hard to implement a self shut-off? Yes. Yes it was. Until Windows 95, all power switches were that - a switch. On or off, nothing else, and there was no "self shut-off". Nor was there a requirement for it. The advent of Windows 95 and the possibility of the system saving state before shutting down cleanly created a market requirement ...


42

That sounds a lot like the Cromemco Cyclops. Released in 1975, it used a modified1 MOS 1kbit DRAM2 to capture a 32×32 black and white or greyscale image. The memory cells were initially set to all 1s. As they were exposed to light they would progressively switch to 0s; the more light hitting a cell, the faster the transition4. By making multiple read ...


42

The situation with the 386(DX) v. 386SX is similar to the situation with the 8086 v. 8088. The big issue isn’t the data lines (although they do have an impact on complexity and cost when routing a whole motherboard), the issue is mostly the cost of support components: motherboard chipsets (whether integrated or discrete), memory, etc. By going back to a 16-...


41

Existing Machinery. Reasoning about the usage of existing packages Adding a few hundred transistors for multiplexing is approximately free compared to buying production machinery for several millions - way before the first chip can be made. Creating a new chip (family) is for sure a risky bet on the future and takes some investment. Keeping this ...


39

I will just explain what a bit is. It's a binary digit. 0 is numerically zero, 1 is numerically one. If you want to add 1 and 1, in binary it overflows. the result is 0, and a carry out. As you understand, other arithmetic operations can be done on bits. They takes a fair bit of logic to implement. Binary is positional. That means that a 1 which is 4 places ...


38

I'm putting CHIP-8 forward. This system is essentially a virtual machine developed for some reason. There are games written for the CHIP-8. It has a few opcodes, a stack, a couple of timers, and a low resolution bitmapped display, but it's simple enough that the first few emulators fit in a few kilobytes on early 8-bit computers. There are more than a few ...


36

It varied immensely, and many early computers have unique architectures that might make answering the question difficult. However the common practice in the earliest days seems to have been large word sizes, suiting their use as pure number crunchers, and their low clock speeds. Most of them were word-addressed, so you could say they had a "byte" equal to ...


36

The architecture of the original IBM PC (and its clones) let the BIOS access the video memory directly. So making nice text layouts did not require positioning the cursor or making a sequence of calls like you would do with curses: It was sufficient to set the text mode at startup and write at the right place in memory the character (1 byte) and its ...


35

CRTs don't have pixels, they don't work that way. Also, arcade monitors expose all the picture controls at the back so it is possible to adjust them quite extensively. Operators would have made sure that the picture was the right shape and in focus near the edges. Since the controls are all analogue and no-one bothered to measure the display geometry the ...


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