Encoders and Decoders

Encoder

• An encoder is a circuit (can be represented as gates) that turns a set of signals into

  • These allow us to become so powerful :)

• 7 Seg Encoder

  • We just take the 4 bit input, and output them according to the seven segments guy, in this case its

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  • our truth table for a the encoder up to 9 is

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    • as you can see that we are stopping at 9, but in our labs we usally use hex to go up to 15

  • To simplify our expression we use karnough maps for each output (so seven k maps :))

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    • in this case since we are only going up to 9 we have all the outputs for anything higher to be dont care because we cant have invalid shit

Decoder

• A decoder is a circuit (can be represented as gates), that changes a code into a set of signals

  • Decoders are usually more simple to design

• Common types of Decdoders

  • 1-2 Line decoder

    • takes an n-digit binary number and decodes it into 2^n data
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    • this can be extrapolated to more bits and stuff

  • 1-4 Line decoder

    • truth table
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    • we can see that the circuit is
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