Questions tagged [memory]
For questions about computer memory in a retrocomputing context
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Did any notable product use Intel's first RAM?
The 3101 SRAM was Intel's first product. At $99.50 for 64 bits, it had enough memory to store the characters expensiv. (Sorry, the final e costs extra.) Is there a record of any product using it?
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How many 6SN7 tubes did it take to store a bit?
One of the most important components of a computer is a circuit called a flip-flop, which has two stable states (that it can flip-flop between, hence the name); it is used for temporary storage of a ...
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How did early laser printers get by with so little memory?
The first HP Laserjet only had 128K of memory. To print an area of 7.5 by 10 inches at 300 DPI requires 844K if it's kept as a single bitmapped image. Obviously they were doing something clever to ...
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Building a Memory Management Unit to expand the 16Bit Address space [closed]
I'm in the middle of making an 8Bit computer, I've selected Z80, the 20Mhz version, which is cheap and readily available. Since Z80 has a 16bit address line it can only address 64KB of memory location....
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Why does the VICE "load" command skip the first two bytes?
I am studying assembly of the C64, and of course using VICE to do so. VICE has the load command to load data straight into the C64 RAM. I reckoned I could use that to put machine code into RAM and run ...
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What were the different RAM refresh techniques in the 80s
I've looked at some techniques that were used at the beginning of the eighties to refresh the RAM (CPU-based refresh for the Z80, or the use of the video circuit for computers that shared the bus ...
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CPU frequency / memory wait states at end of the 80s
According to the advertisements of the late eighties, you could find RAM having an access time ranging from 120 to 80 ns (150 to 210 cycle times). A 386SX-25 could execute a typical register to ...
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How to get back from RAM1 to ROM after setting the bank bit to 1 [closed]
Mapping more than 64kb of address space
regarding cjs answer: How to get back from RAM1 to ROM after setting the bank bit to 1? the next instruction from the program counter would be read from RAM1 ...
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Cheapest type of Read-Only Memory allowing Random access before Year 1970
Back in the 50s and 60s people had:
random access, read-write memories like Magnetic Cores.
sequential access, read-write memories like Delay Lines and Magnetic Tapes.
And:
sequential access, write ...
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How much memory does this SYM-1 have?
I have a SYM-1 with the following memory configuration:
How much memory is that? Those all appear to be L2114UCE chips, which are described as "Static 1024x4 NMOS RAM", but I'm not sure how ...
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Why is EEPROM called ROM if it can be written to?
Is there a historical reason? Since it is rewritable it isn't read only by definition, so why call it so?
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What high nibble values can you get when you read the 4 bit color memory on a C64/C128?
The C64 and the C128 have a memory for storing the color values of a character. The size of this memory is 1k x 4bit (2k x 4bit for the C128 which can do a double buffering), thus reading the value at ...
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Why was the Nintendo 64 bad at textures?
The Nintendo 64 had a reputation for being great at drawing triangles, but not so good at texturing them, so that many games fell back on heavy use of untextured (though Gouraud shaded) triangles, ...
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How fast was Rambus compared to regular EDO RAM?
The Nintendo 64 used Rambus RDRAM. This was an unusual choice, e.g. the PlayStation used regular EDO RAM which I gather most consoles and computers did at the time.
As I understand it, Nintendo chose ...
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Could any computers use 16k or 64k RAM chips?
An interesting feature of the Apple II was that it had three rows of sockets for RAM chips, each of which could take either 4k or 16k chips. That meant the minimum configuration was 4K (cheap) but it ...
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