1. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Activity 1 Grab a whiteboard and pen, come to the front and work out the Truth Table for the following circuit: 5 minutes R A B C Q

2. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits How do the gates work together to process data?

3. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Remembering Last Lesson Binary Logic Circuits In your exam you will be expected to be able to look at a circuit and produce a truth table for the inputs and outputs. Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram A B Q ABQ ?

4. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Worked Example Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram A B P Q INPUTS: A, B, C etc OUTPUTS: P, Q, R etc A B Q = Not AP = (NOT A) AND B 1 1 0 0 1 0 1 0 0 0 1 1 0 0 1 0 P = Q AND B

5. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Tips: 1.Label the inputs on the circuit diagram 2.Label the outputs on the circuit diagram 3.Create a table with a column for each input and output 4.Label the columns (outputs labelled in the form of an expression) 5.Place the combinations of different zeros and ones in the input columns 6.Workout the outputs for each output column in turn Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram A B P Q INPUTS: A, B, C etc OUTPUTS: P, Q, R etc A B Q = A AND BP = NOT (A AND B) 1 1 0 0 1 0 1 0 1 0 0 0 0 1 1 1

6. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Tips: 1.When you place the combinations of different zeros and ones in the input columns…there are patterns that you can remember to help you… Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram A B 1 1 0 0 1 0 1 0 ABC 1 1 1 1 0 0 0 0 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 What if there were 4 inputs? 2 inputs 3 inputs

7. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits This Lesson… Binary Logic Circuit Expressions In your exam you will also be expected to be able to draw a diagram from an expression. Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram A B P A B Q = A AND BP = NOT (A AND B) 1 1 0 0 1 0 1 0 1 0 0 0 0 1 1 1 ? How to we draw a diagram from an expression ?

8. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Binary Logic Circuit Expressions Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram P = A AND (NOT B ) A B P A B P ----BRACKETS FIRST!---- 1st2nd

9. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Binary Logic Circuit Expressions Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram P = NOT ( A AND B ) A B P A B P ----BRACKETS FIRST!---- 1st2nd

10. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Binary Logic Circuit Expressions Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram P = ( A OR B ) AND C A B P A B P ----BRACKETS FIRST!---- 1st2nd C C

11. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Binary Logic Circuit Expressions Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram P = (NOT A) AND B A B P A B P ----BRACKETS FIRST!---- 1st2nd

12. GCSE Computing: A451 Computer Systems & Programming www.computerscienceuk.com Binary Logic Circuits Binary Logic Circuit Expressions Learning Objectives: (a)Explain why data is represented in computer systems in binary form (b)Understand and produce simple logic diagrams using the operations NOT, AND and OR (c)Produce a truth table from a given logic diagram P = ((NOT B) AND C ) OR A A B P A B P ----BRACKETS inside BRACKETS FIRST!---- 1st 2nd C C 3rd