CMPUT 101

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CMPUT 101

• Lab 4
• Section D12
• October 2, 2008
• Fraser Anderson

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Shameless Plug CS Open House

• Come see CS things. They arent all dweeby.
• Virtual reality (my stuff, really cool)
• Ride Segways (still cool)
• Poker (getting nerdier)
• Robots (cool again)
• More stuff (nerdy)
• Saturday, Oct 25, 11-3pm. Free lunch!
• http//www.cs.ualberta.ca/events/openhouse/

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Lab 4 Fun with Paper

• Written questions covering
• Truth tables
• Boolean expressions
• Sum of Products
• Logic circuits
• Binary representation
• Why?
• Logical thinking (how computers make complex
  decisions)

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Truth Tables

• Truth tables show output for all possible inputs.
• A truth table with n inputs has 2n rows.

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Sum of Products

• Creates a boolean expression from a table.
• Find all rows which are true
• For each row, logically AND the values together.
• Logically OR all of the previous ANDed values.
• AB AB AB

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Sum of Products

• Creates a boolean expression from a table.
• Find all rows which are true
• For each row, logically AND the values together.
• Logically OR all of the previous ANDed values.
• AB AB AB

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Logic Circuits

• Graphical representation of boolean expression
• Draw NOT
• Draw AND
• Draw OR
• ABC ABC AC

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Binary Representation

• Unsigned
• Sign/Magnitude

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Binary. Cont.

• Original

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Binary.. Cont.

• Original
• Flip the bits, if necessary.

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Binary... Cont.

• Original
• Add one, if necessary.

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Binary.... Cont.

• Original
• It is now sign/magnitude, convert to decimal.

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Conclusion!

• When youre done, hand in your papers, sign the
  sheet.
• No more labs for a while.
• I will be in the lab after the assignment is
  released
• If you need help with something specific, email
  me
• frasera_at_cs.ualberta.ca
• Watch moodle for updates