Most semiconductor memory is organized into memory cells or bistable flip-flops, each storing one bit (0 or 1).
How exactly are the needed '1's or '0's taken from Memory? What mechanism or algorithm?
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\$\begingroup\$ If you'd like to change the emphasis of your question, please just edit the question you already asked. Even the title can be edited (I do like the new title better). \$\endgroup\$– The PhotonCommented Aug 24, 2013 at 16:57
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\$\begingroup\$ @ThePhoton while poorly worded I think this question is more about HOW the memory works, i.e. sense amplifiers (in DRAMs case) vs. how the computer "knows" what memory to access. \$\endgroup\$– placeholderCommented Aug 24, 2013 at 17:37
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There are many types of memory (even when you limit the type to semi-conductor memory and not spinning disks types) within a computer.
Generally latches, registers, cache memory are all SRAM based and output signal levels that are compatible to the surrounding logic. You can consider them to be part of the logic so there is no special techniques used in accessing them. Consider them to have built in logic buffers at the transistor level.
Other types of memory like DRAM , Flash RAM etc. which operate on stored charge have to have intermediary circuits between them and the reading/writing circuits. The signal is present as very small charges which are read directly or is used to parametrically shift an operating point of a read transistor. These circuits are called sense amplifiers. One simplistic but close view is that the buffer amplifiers mentioned above are moved to the periphery and then reused for every circuit thereby reducing the total amount of circuitry used.
answered Aug 24, 2013 at 17:57
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So, imagine you have a room of people, each one has a unique name. When you call out Abel, only Abel shouts out.
So same with memory, even though all the people in the room are 'connected' to the ears of the instructor, they don't yell out unless called. They are in a high impedance state. They don't affect the sound in the room until called.
Memory cells are all connected to the same wire. But each memory cell stays in its high impedance state and doesn't put anything on the line until, it's called.
So the CPU says, I need memory 59, that memory number 59 goes into drive state and puts whatever it has in itself onto the line, while memory 58 and all others stay high impedance, or quiet.
