How Computers Work
half adder
XOR(sum)+AND(carry)
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Logic From SwitchesHow Computers WorkMore terms from this board
- abstraction laddereach layer built from the one below and hiding it: transistor → gate → adder/register → CPU. Moore's law = transistors-per-chip roughly doubling every ~2 years.
- ALUarithmetic logic unit (the adder + more)
- AND/OR/NOT/XORboth/either/invert/differ
- clockthe tick that advances flip-flops
- combinationaloutput depends only on current inputs
- flip-flop / latch1 bit of memory via feedback
- full adderadds a carry-in
- logic gatea circuit computing a boolean rule
- NAND (NOT-AND)UNIVERSAL — builds every other gate
- ripple-carrychained full adders
- SRAMfast memory made of flip-flops (cache)
- transistor (MOSFET)a voltage-controlled switch
- truth tablethe gate's full input→output map