The System Unit Michael Rodriguez Communications 165 T&Th 9:30-10:45

What It Is  It is also commonly known as the system cabinet or chassis  3 kinds of system units  Desktop: Stationary units  Notebook system units: Portable units  Personal digital assistant (PDA): smallest system

Binary coding schemes  ASCII is the most widely used for microcomputers  EBCDIC was developed by IBM and is used primarily by large computers  Unicode is a newly developed code dependent on 16 bit code. It is used to support international languages

System Board CCCCommonly known as the motherboard, but it is also known as the main board  C C C Chips AAAAlso called a silicon chip, semi conductor, or integrated circuit TTTThey are the size of a postage stamp

Microprocessor  Control unit  Arithmetic-logic unit  Smart cards  microprocessor chips –Complex instruction set computer (CISC) –Reduce instruction set computer (RISC)

Memory  Ram (random access memory)  Flash ram  Virtual memory  Memory cache  ROM (read only memory)  CMOS (complementary metal-oxide semi conductor)

System Clock  On a small chip that acts as a pacemaker of the computer  Measured in gigahertz (GHz) or billionths of a second

Expansion slots and cards Expansion Cards only accepted in open architecture systems because only the open ones have slots for the Cards Different types of Cards Network Adapter Cards Modem Cards TV tuner cards PC cards

Bus Lines  Bus lines or data buses or buses  ISA industry standard architecture  PCI peripheral component interconnect  AGP accelerated graphics port  USB universal serial bus

Ports and cables  5 most common types –Serial –USB –Parallel –HPSB –FireWire  Cables –Used to connect I/O devices to the system via ports

The End