Introduction

• We will study computer orginization to understand how to build the compoinents we have been discussing
  • RF, ALU, MMU, Memory, IR, PC, CU
• The purpose is to understand the basis for implementing a computer.
  • This is not a computer enginnering course, and I have no training in that area.
  • What we look at will work, altho it might not be the most efficieint.
  • The goal is to understan how things work.
• These are mostly built from simple gates.
• We will focus on and, not and or as our basic components.
  • This is probably not what things are actually built out of, more likely not, nor and nand.
  • But we will work from here.
• combinational logic is a circuit with no memory, output is determeind by input.
• sequential logic is a circuit with a memory.
• Transistors:
  • A transistor is a simple device with has three terminals
  • A base, a collector and an emitter
  • A high or low charge can be applied to the base
• For a PNP
  • 
  • A high source is applied to the emitter.
  • If the base is switched to low, the collector goes to high
  • If the base is switched to on, the collector is neutral.
• For a NPN
  • 
  • A low source is applied to the emitter.
  • If the base is switched to low, the collector goes to neutral
  • If the base is switched to high, the collector is low.
• Look at this tkgate file.
• Basic gates can be obtained by combining transistors.
  • Look at the tkgate file for not, nor, and nand.
  • Develop the truth table for not, nand, nor
  • Establish the relationship between truth table and circuit.
• Some things to note in TKGATE
  • Comments are REQUIRED
  • Don't spend forever fixing your wires, but do make things readable.
  • Depending on your usage, tkgate may crash.