CS6303 CA Notes, COMPUTER ARCHITECTURE Lecture Notes – ECE 6th SEM Anna University

CS6303 – COMPUTER ARCHITECTURE

LESSON NOTES

UNIT I

OVERVIEW & INSTRUCTIONS
Embedded Computer: Performs single function on a microprocessor

•  Embedded within a product (e.g. microwave, car, cell phone)
•  Objective: Low cost
•  Increasingly written in a hardware description language, like Verilog or VHDL
•  Processor core allows application-specific hardware to be fabricated on a single chip.Desktop Computer: Designed for individual use

Also called personal computer, workstation
Server: Runs large, specialized program(s)

•  Shared by many users: more memory, higher speed, better reliability
•  Accessed via a network using a request-response (client-server) interface
•  Example: File server, Database server, Web serverSupercomputer: Massive computing resources and memory

•  Hundreds to thousands of processors within single computer
•  Terabytes of memory
•  Program uses multiple processors simultaneously
•  Rare due to extreme expense
•  Applications: Weather forecasting, military simulations, etc. What types of applications are concerned about:

•  Memory?
•  Processing speed?
•  Usability?
•  Maintainability?

From the CPU’s perspective, an I/O device appears as a set of special-purpose registers, of three general types:

•  Status registers provide status information to the CPU about the I/O device. These registers are often read-only, i.e. the CPU can only read their bits, and cannot change them.
•  Configuration/control registers are used by the CPU to configure and control the device. Bits in these configuration registers may be write-only, so the CPU can alter them, but not read them back. Most bits in control registers can be both read and written.
•  Data registers are used to read data from or send data to the I/O device.