Unformatted text preview: components of the computer.
Lecture Unit 1 ECE15: Introduction to Computer Programming Using the C Language 5 Hardware: Main Components
Input Devices: Usually, keyboard and mouse. But also anything that can serve to input information into a computer, e.g. eye-tracker. Output Devices: Usually, monitor and printer. But also anything that serves to get data/information/signals out of a computer. Storage Devices: This is where all files are stored. Unlike the RAM memory, these devices are non-volatile: stored data does not disappear when power is turned off. However, these devices are much slower than RAM. Examples include: magnetic hard disk, flash memory, CD and DVD, magnetic tape.
Lecture Unit 1 ECE15: Introduction to Computer Programming Using the C Language 6 CPU: Frequency and Clock Cycles
Programs are converted into sequences of elementary instructions for the CPU. These instructions are then carried out using an internal clock. Thus the speed of a computer is roughly proportional to: number of clock cycles per second = frequency Examples:
1984: First Macintosh -- 8MHz (eight million cycles per second) 1993: Intel486 Processor -- 33MHz (used in most PCs of that era) Today: Nokia6680 cell phone 280MHz, Intel Pentium4 up to 3800MHz Note: Each elementary CPU instruction takes several clock cycles. For instance, multiplication takes many more clock cycles than addition.
Lecture Unit 1 ECE15: Introduction to Computer Programming Using the C Language 7 Main Components of the CPU
Arithmetic Logic Unit (ALU): The heart of the CPU where computation is performed. Computation is broken down into simple operations, such as: ‣ Arithmetic operations (addition, multiplication, etc.) ‣ Logic operations (AND, OR, etc.) ‣ Comparisons of data in the RAM memory or in CPU registers
CPU Registers: Small number of memory units that allow especially fast access. Access to registers is much faster than access to RAM. One of the registers serves as the program counter, pointing to the instructio...
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This note was uploaded on 04/15/2010 for the course ECE ECE15 taught by Professor Vardy during the Fall '08 term at UCSD.
- Fall '08
- Computer Programming