CSCE101 – 4.1, 4.2 and Number Systems October 5 & 10, 2006

Study Tree Part II Computer as a State Machine (4.1+) Binary Numbering System And Computing (4.2+) Number System Conversions

4.1 Microchips, Miniaturization & Mobility Transistor – key component in all modern electronics Vacuum tubes to discrete transistors to integrated circuitry Transistors –Modulate electric current –Act as switches Integrated circuit – chip, contains other circuitry to control current

4.1 Microchips – cont. Microchip or chip contain millions of circuits (interconnections of electronic components) Circuitry is solid-state Circuitry is embedded on silicon Silicon is a semi-conductor Photolithography etches the circuit design onto a wafer in layers Wafer is cut into chips Chips are mounted in a protective frame

4.1 Microchips – cont. Different kind of chips – RAM, ROM, CPU Circuitry is designed differently for various chips All are sets of transistors (switches) in on/off state at any given instant (panels of blinking lights, anemones) Computer is a state machine – runs through a series of states to produce result.

System to represent the state machine On-off, x-y, 1-0 Number systems –Decimal –Base 20 –Octal –Hexadecimal (Web pages, URLs) –Binary

In the machine… Using binary to represent all of the following: –Data and Information (Numbers and Letters) –Instructions –Arithmetic operations –Logical operations –Error-checking (Parity Checking) Bit, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte

Representations Data and Information –Numbers –EBCDIC –ASCII –UNICODE BinaryDecHexGlyph A B

Representations Data and Information –Numbers –EBCDIC –ASCII –UNICODE Instructions –Each processor has its own representation of instructions (its own machine language) –For example adding the registers 1 and 2 and placing the result in register 6 is encoded: [ op | rs | rt | rd |shamt| funct] binary decimal

Conversions Binary to Decimal Binary to Hexadecimal Hexadecimal to Decimal Hexadecimal to Binary Decimal to Binary Decimal to Hexadecimal

Representations (continued) Binary arithmetic –Addition –Subtraction Binary (Boolean) Logic –George Boole –Claude Shannon –Propositional Logic =if(B16>600, “Car payment can be made”, “Car payment cannot be made”)

System Unit 1.Display 2.Motherboard 3.CPU (Microprocessor) 4.Primary storage (RAM) 5.Expansion cards 6.Power supply 7.Optical disk drive 8.Secondary storage (HD) 9.Keyboard 10.Mouse