ECE 223 LAB 1

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ECE 223 LAB 1

• Preetha Thulasiraman
• pthulasi_at_bbcr.uwaterloo.ca
• Winter 2007

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What you need to do

• Part 1 Gear Shifter System
• Part 2 Decoder for Seven Segment Display
• Demonstrations
• Lab Report

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Part 1 Gear Shifter System

• Inputs (w, x, y, z)
• Gear Position
• Gear Request

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• Outputs
• Enable
• Direction
• Enable Direction
• 1 ? Shift gears 1 ? Shift gear up
• 0 ? Do nothing 0 ? Shift gear down

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Example

• To shift from second to neutral

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• Design
• A) use 2 input NAND gates
• B) use any gates available, minimize as much as
  possible
• Hint Use K-maps
• Consider invalid cases
• What happens to your design if 4th gear added
• Implement one of your designs using TTL gates and
  speedwire
• Simulate and test design

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Part 2 Decoder for Seven Segment Display

• Inputs w,x,y,z, blanking input
• If blanking input is 1 display is blank
• Outputs a,b,c,d,e,f,g
• 0001 A
• 0010 B
• 1010 J

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Example

• To show letter A
• Seven segment display is ACTIVE LOW
• Use K-maps, dont use blanking input in maps
• Have a K-map for each output
• Simplify design by noticing similarities between
  and within maps

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Help Sessions

• For lab help sessions
• Do most of design work BEFORE coming to the lab
• i.e. problem analysis, K-maps, VHDL code,
  schematics must be done

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Demo

• Day of demo must show
• VHDL code, simulation and schematics for both
  parts
• Hardware must work to receive full points
• VHDL code must work
• Answer questions about your implementation
• Print out and bring submission form

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Final Report

• Lab submission form (front page)
• Include
• Problem definition/specification
• Circuit design information
• Final circuit schematic
• Simulation command files
• Simulation waveforms
• VHDL code
• Show all intermediate designs (i.e. K-maps, truth
  tables etc.)
• Discuss debugging strategies, problems
  encountered, provide an analysis of your work