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5

For the origin of fixed size pages, and independently mapped pages, you need to go back at least as far as the Manchester Atlas machine of 1962. A historical perspective of both the Atlas ad the earlier Mark I can be found here. In that article it mentions that Atlas memory was divided into fixed size pages of 512 words each. The idea of separating virtual ...


2

An observation I have made recently is that only things which involve a lot of material have a natural bottom price. A washing machine weighs 100 pounds, a car weighs 2000, a house 200,000 (or whatever). People have to dig coal and ore out of the earth, make steel, fell trees, truck it to processing plants etc. No amount of automation or technological ...


1

For the same reason as: CPUs increasing in frequency from sub-MHz to multi-GHz CPUs increasing in number of cores from a single core to several dozen Hard disk drives increasing in capacity from a few MB to several TB Modems increasing in speed from a few hundred bit/s to gigabits/s Wi-Fi increasing in speed from 2 Mbit/s to gigabits/s Ethernet increasing ...


4

Since the invention of ICs, computer memory size has been gated by Rock's law, or Moore's second law. At any point in time, no one could afford the rapidly growing costs (now many $billions USD) it took to build the more advanced semiconductor fab lines that are required for smaller lithography higher density memories, until the market grew enough, and ...


5

The brief answer to the question is we watched the evolution of computer technology from computers that filled a room and cannot hold a candle to a watch we can wear on our wrist. You might as well ask why we didn't have cars that could do 200 mph back in 1900. Part of the answer to your question is R&D the other part is paying for that R&D. Remember ...


6

Most likely reason I think is that when NiCd batteries discharge, they stay at almost 1.2V for most of their discharge cycle then go from 1.2 to 0 volts very quickly, so the low batt warning is unlikely to be on for very long if at all, and the player being unable to save the game, if it simply turns itself off with little to no warning. Since alkaline ...


7

On my windowsill, I've got (roughly) 2K bits of core memory in a picture frame. According to an engineering manager it was assembled by Philippina seamstresses, and they were able to do it for about three years before their eyesight failed. He sounded smug rather than horrified. Each core, representing one bit, has four wires threaded through it. If we ...


14

Didn't people living at that time feel sudden reductions in size/availability as technologies evolved? And if they didn't, why wasn't there a "jump" in memory availability when technology reached a certain state? Yes - except that since it happened on an annual basis, we got used to having jump after jump after jump in technological capability. It ...


26

I'm mostly concerned about RAM. Why was it so expensive? It wasn't - at least not once integrated circuit RAM became available in the 1970s. Compared to other chips, RAM was cheaper both per transistor and per package. Some example prices:- From an advert in Byte magazine issue #1 (Sept 1975) 8080 CPU: (4,500 transistors) $149.95 = $33 per thousand ...


43

As noted in some initial comments (but I feel fine answering, as I had the exact same ideas when I read the question), this is a general progression of technology but there are two very specific factors for RAM: Core Memory -> Integrated Circuits While many different, very expensive, systems were used in the first computers, including mercury delay lines, ...


35

I suspect more "don't disappoint the users" than "harm to the device". From the Wikipedia AA article, not only is the nominal voltage lower (1.2V vs. 1.5V for both alkaline and cheap zinc-carbon), the "Max. energy at nominal voltage and 50mA drain" is *significantly lower: Alkaline = 3.90 Wh = 52 hours (3.9 Wh/50mA/1.5V = 52) ...


21

Two simple reasons. Different battery chemistries have different voltage and safety. Standard alkaline batteries are nominally rated for 1.5V, but they can have more than 1.6V when brand new and are considered to be discharged at around 1.1V or so, depending on application. Standard rechargeable batteries that are intended to be used in place of standard ...


0

I guess one should add as well what might be the first computer with a redefinable character set: The Cogar 4 The 1971 Cogar 4 is not only a tight contender for the first desktop PC(*1), but as well did store the definition of its character set in RAM. All 128 possible characters could be defined as a 5x8 bitmap as describend on page 9 of the Systems Summary....


2

On the Soviet home computers of the series BK (BK-0010, BK-0011, BK-0011M, which were clones of LSI-11), the fonts could be loaded directly into memory, when using many operating systems, like ANDOS, MKDOS, AO-DOS. The OS shell had an option to save the current appearance for the next OS load. Below, an ANDOS file manager with a custom font enabled and a ...


7

It may be impossible to give a simple answer, as a design is influenced by many parameters. Complexity (and thus price) might being one A notable difference between these three games are the number of digits displayed, which goes direct into circuit complexity. Pong has two 1.5 digit counters (0..15) (*1) Speed Race has two 3 digit counters Breakout has ...


2

The 6502 only uses one phase of the clock for memory accesses. The other phase can be used for access to memory for other purposes. The Apple II used this technique. It did not use READY (although that was available on the peripheral bus). This idle phase of the clock was used for providing the data for the the display at the required refresh rate. By ...


1

It really comes down to getting good performance on the Amiga requiring a lot more time and skill than on the Megadrive. The Sega machine makes it very easy to do things like parallax scrolling and large sprites. The Amiga is capable, but requires a lot more effort to tease the performance out. There are other fighting games on the Amiga, like Shadow Fighter ...


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