CMPSC 64 Lecture Notes - Lecture 1: Arithmetic Logic Unit, Central Processing Unit, Nibble
Document Summary
From hardware (keyboard, mouse, etc. ) or from a program. From hardware (display screen, speaker, etc. ) or to a program. Secondary data storage i. e. hard-drive, ssd, cd-rom, etc. Binary bit = the smallest representation of the data. Ascii used 7 bits to convey one character. Expressing data and instructions in either 1 or 0 Does the actual processing in a computer cpu. Good at doing arithmetic (+, -, *, /) Does calculations in binary using registers (small ram) and logic circuits. Handles breaking down instructions into control codes for the alu and memory. This is what happens inside a computer interacting with a program at the lowest level. Instructions get executed in the cpu in machine language (in 1s and 0s) Each instruction needs multiple cycles of the cpu to get executed fully. Cpus can run many millions of instructions per second, so this doesn"t matter. In low-level languages, you need to spell the cycles out.